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Advancements in Drought and Salt-Tolerant Crops: A Comparison of Breeding and Genetic Engineering Approaches

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Ritwik Acharya, Madhushri Das Datta, Debnirmalya Gangopadhyay, Shubhajit Shaw, Rahul Chatterjee and Ankita Manna

Submitted: 08 May 2025 Reviewed: 20 May 2025 Published: 07 July 2025

DOI: 10.5772/intechopen.1011113

Advances in Plant Breeding - From Techniques to Stress Tolerance IntechOpen
Advances in Plant Breeding - From Techniques to Stress Tolerance Edited by Murat Aycan

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Advances in Plant Breeding - From Techniques to Stress Tolerance [Working Title]

Dr. Murat Aycan

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Abstract

Drought and salinity are major abiotic stresses threatening global agriculture, necessitating resilient crop development. This review compares traditional breeding and genetic engineering approaches to enhance stress tolerance. Traditional methods—such as selection, hybridization, and marker-assisted breeding—have achieved moderate gains but are limited by complex trait inheritance and lengthy breeding cycles. In contrast, genetic engineering enables precise and rapid improvements through transgenic expression of stress-responsive genes (e.g., DREB, NHX1, Late Embryogenesis Abundant (LEA)) and genome-editing tools like CRISPR/Cas9. Key physiological and molecular responses include stomatal regulation, ion homeostasis, osmotic adjustment, and antioxidative defense. Field successes like MON 87460 maize and Bt cotton illustrate the potential of biotechnological interventions. This review emphasizes integrative strategies combining molecular genetics, genomic selection, and high-throughput phenotyping for effective crop improvement. While genetic engineering holds significant promise, it faces challenges related to technical constraints, regulations, and socio-ethical concerns, especially in developing countries. The review advocates a synergistic model that blends the strengths of conventional breeding with gene-editing precision to accelerate the creation of climate-resilient crops. This concise synthesis supports innovation in plant biotechnology to sustain agricultural productivity under escalating environmental stress.

Keywords

  • drought tolerance
  • salt stress
  • genetic engineering
  • traditional breeding
  • CRISPR/Cas9
  • climate-resilient crops

1. Introduction

Climate change and increasing global food demands have underscored the urgent need for crops capable of withstanding challenging environmental conditions, particularly in arid and semi-arid regions where agricultural productivity is most vulnerable. Among the numerous abiotic stresses that threaten crop yields, drought and soil salinity are two of the most critical factors limiting agricultural output on a global scale [1, 2]. These stresses disrupt plant physiological and biochemical processes, ultimately reducing growth and productivity. Alarmingly, by 2050, it is projected that more than half of the world’s arable land could be severely affected by water scarcity and salinity stress [3]. This looming crisis poses a major threat to global food security, particularly in regions already facing food shortages. As conventional agricultural practices struggle to keep pace with these mounting environmental pressures, there is an increasing need to develop resilient crop varieties to withstand such stresses to achieve sustainable agriculture and long-term food security [4]. Figure 1 summarizes the impact of drought and salinity on stress-sensitive plants and highlights the superior performance of stress-tolerant plants under these adverse conditions.

Figure 1.

Impact of drought and salinity on stress-sensitive plants and the superior performance of stress-tolerance plants under these adverse conditions.

To address these challenges, traditional plant breeding methods have been used to enhance crop tolerance to drought and salinity. These strategies have yielded significant improvements in some crops [5]. However, conventional breeding is often a slow and labor-intensive process, constrained by the limited genetic variability available within a species [6]. The emergence of genetic engineering and molecular biotechnology has revolutionized crop improvement strategies. These advanced tools enable the direct manipulation of specific genes associated with stress responses, allowing for the development of genetically modified crops with enhanced tolerance to drought and salinity [7]. Such innovations hold immense potential for future agriculture.

This article delves into the significant advancements achieved through both traditional breeding and modern genetic engineering strategies aimed at enhancing drought and salt tolerance in crops. By critically examining and comparing their underlying methodologies, key achievements, limitations, and potential for large-scale application, we seek to offer a well-rounded and in-depth perspective. The discussion highlights how these approaches contribute to improving crop resilience under abiotic stress conditions and evaluates their roles and future prospects in promoting sustainable and climate-resilient agriculture.

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2. Physiological and molecular mechanisms underlying plant tolerance to drought and salinity stresses

Plants have developed a sophisticated array of physiological and molecular strategies to survive drought and salinity, two major abiotic stresses that significantly constrain global agricultural productivity. These stresses disrupt water balance, ion homeostasis, and metabolic function, prompting plants to initiate multifaceted tolerance responses that span from whole-organism adjustments to molecular-level regulation.

At the physiological level, drought stress leads to a reduction in water availability, compelling plants to optimize water-use efficiency. A key mechanism involves the regulation of stomatal aperture through abscisic acid (ABA)-mediated signaling, which reduces transpiration-driven water loss [8]. Osmotic adjustment, achieved through the accumulation of compatible solutes such as proline, glycine betaine, and trehalose, helps maintain cellular turgor pressure and stabilizes proteins and membranes under water-deficient conditions [5]. The root system architecture also adapts to drought, with increased depth and density facilitating water uptake from deeper soil layers [9].

Under salt stress, plants face ionic toxicity and osmotic imbalance, primarily due to excessive sodium (Na+) uptake. To combat this, selective ion transport mechanisms restrict Na+ entry and sequester excess Na+ into vacuoles via Na+/H+ antiporters, thereby preserving cytoplasmic ion homeostasis [2]. Maintaining a high potassium-to-sodium (K+/Na+) ratio is crucial for sustaining enzymatic activity and metabolic functions [10].

Both drought and salinity also trigger the overproduction of reactive oxygen species (ROS), such as superoxide radicals and hydrogen peroxide, which cause oxidative damage to cellular components. In response, plants activate enzymatic antioxidant defenses, including superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), which detoxify ROS and mitigate oxidative stress [11]. Photosynthetic efficiency is safeguarded through non-photochemical quenching and chloroplast-based antioxidant systems that minimize photodamage and maintain energy production under stress [12].

Central to these physiological defenses is the ABA signaling pathway, which not only regulates stomatal closure and osmotic adjustment but also interacts closely with ROS detoxification mechanisms. This crosstalk enables plants to orchestrate a coordinated stress response, integrating hormonal signaling with redox regulation. Transcription factors such as DREB and MYB serve as crucial mediators in this network, regulating the expression of stress-responsive genes involved in osmoprotection, antioxidative defense, and ion homeostasis [2].

On the molecular level, stress perception at the cell membrane activates complex intracellular signaling cascades. Secondary messengers, such as calcium ions (Ca2+), ROS, and phospholipids, initiate these responses by activating kinases, including mitogen-activated protein kinases (MAPKs) and calcium-dependent protein kinases (CDPKs), which in turn regulate downstream gene expression [11, 13]. Major transcription factor families—such as DREB, NAC, MYB, and bZIP—control the transcription of genes encoding osmoprotectants, ion transporters, and antioxidants [14]. Under drought, ABA biosynthesis and signaling genes, including NCED and AREB1, are upregulated to enhance tolerance through stomatal regulation and osmotic balance [15]. During salt stress, the Salt Overly Sensitive (SOS) pathway becomes crucial, with SOS1 functioning as a plasma membrane Na+/H+ antiporter that expels excess Na+ and maintains ionic equilibrium [16].

Additionally, gene expression is modulated post-transcriptionally by small RNAs, particularly microRNAs (miRNAs), which fine-tune stress responses by targeting mRNAs for degradation or translational inhibition [17]. Epigenetic modifications, including DNA methylation and histone acetylation, contribute further to stress adaptation by regulating chromatin structure and enabling stress memory, thereby priming plants for enhanced responses to recurrent stresses [18].

Collectively, these multilayered physiological and molecular mechanisms equip plants with the resilience necessary to survive environmental adversities. Deciphering these complex networks offers critical insights for crop improvement strategies aimed at enhancing stress tolerance in the face of ongoing climate change.

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3. Breeding approaches for developing tolerant crops

Abiotic stresses, such as salinity and drought, significantly constrain global agricultural productivity, threatening food security under changing climatic conditions [19]. Developing crop varieties with enhanced tolerance to these stresses is therefore a critical objective in plant breeding programs. Conventional breeding, marker-assisted selection, and transgenic approaches have been employed to incorporate stress-tolerance traits into high-yielding cultivars [20, 21].

3.1 Traditional breeding methods

Traditional breeding techniques have been pivotal in developing crop varieties resilient to environmental stresses. These methods, which include selection, hybridization, and mutation breeding, aim to enhance stress tolerance by leveraging natural genetic variability. Selection involves identifying and propagating plants with desirable traits, such as drought tolerance or disease resistance, through iterative cycles over generations, leading to improved stress-resilient varieties. Hybridization, by crossing genetically diverse parental lines, combines advantageous traits to produce offspring with superior stress tolerance and performance. Mutation breeding, which employs chemical or radiation-induced mutagenesis, facilitates the emergence of novel traits—including enhanced stress tolerance—that are subsequently integrated into breeding programs [22, 23]. Collectively, these approaches have played a crucial role in advancing the development of drought- and salt-tolerant crop varieties, enabling farmers to combat the detrimental effects of water scarcity and soil salinity [24, 25].

3.2 Marker-assisted selection (MAS) and quantitative trait loci (QTL) mapping

Quantitative traits, such as those related to drought and salt tolerance, are typically governed by a complex interplay of genetic and environmental factors. The genomic regions controlling these traits, known as quantitative trait loci (QTLs), are specific segments of the genome associated with particular traits. Advances in molecular genetics have greatly facilitated the identification of QTLs, initially driven by the development of linkage maps in the 1980s. These maps enabled the generation of mapping populations and the identification of polymorphic markers, establishing critical linkages between molecular markers and QTLs [26].

Molecular markers, categorized into protein-based markers (e.g., isozymes) and DNA-based markers (e.g., RFLP, AFLP, SSR, and SNP), have proven instrumental in marker-assisted selection (MAS). MAS accelerates the breeding process by selecting favorable alleles, improving complex traits such as drought-related yield and difficult-to-measure traits like root architecture, water-use efficiency, and osmotic adjustment. Moreover, these markers facilitate the introgression of desirable traits from wild relatives, reducing linkage drag by minimizing the unintended co-transfer of undesirable genes [27].

Recent advancements extend beyond marker-based approaches to include gene identification strategies within QTL regions. Traditional map-based cloning is now complemented by high-throughput technologies such as microarray-based transcriptional profiling, which elucidates differential gene expression under stress conditions [28, 29]. Integrative approaches combining genetic mapping with expression profiling have further refined the identification of candidate genes associated with stress tolerance [30, 31]. For example, Huang et al. [32] identified approximately 2000 drought-responsive genes in Arabidopsis thaliana, with a significant proportion regulated by abscisic acid (ABA). Similarly, Seki et al. [33] reported 277 drought-responsive genes, many of which also respond to cold and heat stress, highlighting the overlap in abiotic stress responses.

QTL studies in crops such as wheat, rice, cotton, oilseeds, and forage species have underscored the utility of MAS for improving drought and salinity tolerance. Advanced backcross QTL analysis has also been employed to assess donor introgressions within elite genetic backgrounds, enhancing the efficiency of breeding programs [34]. Additionally, QTL mapping studies have identified numerous loci involved in salt stress responses [31, 35]. These developments underscore the transformative potential of molecular markers and integrative genomic approaches in accelerating the development of stress-tolerant crops, paving the way for sustained agricultural productivity under challenging environmental conditions [36].

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4. Genetic engineering approaches for enhancing drought and salinity tolerance in crops

Genetically modified (GM) crops have emerged as powerful tools to combat the increasing threat of abiotic stresses such as drought and salinity. These crops are developed using precise genetic engineering techniques that involve the insertion of foreign genes into plant genomes through methods like Agrobacterium-mediated transformation or direct gene transfer, leading to the creation of transgenic plants [37]. Unlike traditional breeding, which is limited by species compatibility, genetic engineering allows the introduction of genes across taxonomic boundaries, thereby accelerating trait enhancement [38].

A major focus of genetic modification is improving tolerance to complex, multigenic stresses such as salinity and drought. Salt stress activates several physiological responses in plants, including osmolyte accumulation, activation of antioxidant systems, and regulation of ion homeostasis. Incorporating salt-tolerance genes from halophytes or modulating native stress-responsive genes enhances ionic regulation and stress signaling pathways. Notably, chloroplast-targeted expression of osmolyte biosynthetic genes has shown superior outcomes, indicating that subcellular localization plays a pivotal role in transgene performance [39, 40]. Similarly, the introduction of genes related to drought tolerance, such as those encoding transcription factors, aquaporins, Late Embryogenesis Abundant (LEA) proteins, and enzymes involved in osmolyte biosynthesis, has improved water-use efficiency and conferred protection against cellular dehydration [41, 42]. Prominent examples include MON 87460 maize and transgenic rice expressing CSPB, Ubi1::TPSP, and NHX1, which have demonstrated enhanced tolerance under field conditions, supporting their agricultural viability.

Improving abiotic stress resilience is critical for ensuring global food security amid escalating climate change impacts [43]. Molecular breeding and biotechnology have focused on manipulating key transcription factors such as DREBs [44] and on leveraging LEA proteins, which stabilize macromolecules under stress due to their hydrophilic and thermostable nature [41]. Genetic modification of ion transporters like HKT1 and NHX1 has also proven vital for salinity tolerance by maintaining ionic homeostasis [45, 46]. Further, enhancing the expression of heat shock proteins (Hsps) has been shown to improve thermotolerance in several crops, as demonstrated by Bhatnagar-Mathur et al. [7].

CRISPR/Cas9 genome editing has recently revolutionized crop improvement by allowing precise modifications of stress-related genes [47, 48]. For example, DREB transcription factors confer stress tolerance, but constitutive overexpression may cause growth defects. Using stress-inducible or tissue-specific promoters allows for localized expression, mitigating growth penalties while maintaining stress resilience [40]. In soybean, overexpression of DREB1A improved drought response in greenhouse conditions through reduced water use, although field yields remained unchanged [44, 49].

LEA proteins, initially identified in seeds, have been recognized for their protective roles in vegetative tissues under abiotic stress. They are grouped into seven subfamilies and are highly expressed across plant genomes: 51 genes in Arabidopsis, 34 in rice, 108 in Brassica napus, and 23 in Phyllostachys edulis [50, 51]. Transgenic expression of wheat-derived group I and II LEA genes (PMA1959, PMA80) in rice enhanced drought and salinity tolerance [52], while OsEm1 upregulated other LEA genes under stress [53]. Group II proteins, such as RAB16A and SmLEA2, improved antioxidant defenses [54, 55], and group III members, such as HVA1 and OsG3LEA-47.3, imparted combined drought and heat tolerance [56, 57]. Additionally, atypical group V proteins, such as AdLEA from Arachis diogoi, enhanced multiple stress tolerances in tobacco [58].

Sodium transporters play a pivotal role in salinity stress responses. In rice, OsHKT1;1 restricts Na+ accumulation in shoots and is regulated by the MYB-type transcription factor OsMYBc, which binds directly to its promoter. Mutants lacking OsMYBc show diminished OsHKT1;1 expression and increased salt sensitivity [45]. Similarly, vacuolar sequestration via NHX1 and cytoplasmic Na+ efflux by SOS1 work synergistically to maintain Na+/K+ balance. Individually, these transporters are insufficient under high salinity (>200 mM NaCl), but co-expression of AtNHX1 and AtSOS1 in Arabidopsis allowed tolerance up to 250 mM NaCl with no yield loss [46].

The heat shock response is orchestrated by heat shock transcription factors (HSFs), which become activated upon stress and promote the expression of Hsps that stabilize proteins and form stress granules [7, 59, 60, 61, 62]. This response is increasingly harnessed in transgenic plants to improve thermotolerance.

Salinity disrupts nutrient balance, membrane function, and photosynthesis due to elevated Na+ and Cl [63, 64, 65], which plants counter through ion transporters and reactive oxygen species detoxification [2]. CRISPR/Cas9 offers a precise solution to these challenges. As illustrated in Figure 2, CRISPR/Cas9 enables targeted knockouts or overexpression of genes related to drought and salinity tolerance, allowing fine-tuned genetic interventions. Examples include overexpression of SOS1 and HvHKT2;1 in Arabidopsis and barley for enhanced Na+ transport [66, 67]. In rice, CRISPR knockouts of OsRR22, OsPQT3, and OsmiR535 improve salt stress tolerance [47, 68]. Similarly, editing SlHyPRP1 in tomato and ACQOS in Arabidopsis boosts stress resilience [48, 69]. Drought tolerance is polygenic and difficult to improve through traditional methods [70, 71]. CRISPR addresses this by modifying genes such as DERF1, MYB5, SPP, OST2, and miR169a in rice and Arabidopsis [72, 73], as well as ARGOS8, abh2, and ERA1 in cereals [74, 75, 76, 77]. Successes in rapeseed, wheat, tomato, and cotton validate CRISPR’s broad applicability in engineering climate-resilient crops [78, 79]. A summary of major CRISPR-mediated improvements in abiotic stress tolerance is presented in Table 1.

Figure 2.

The mechanism of CRISPR/Cas9-mediated development of drought and salt tolerance in plants.

PlantTargeted gene(s)Gene functionTarget traitReference
RiceDERF1, PMS3, MSH1, MYB5, SPPInvolved in amino acid biosynthesis and regulation of drought-responsive genes; enhances tolerance via metabolic adaptation and stress-responsive transcription.Drought toleranceZhang et al. [80].
RiceERA1Negative regulator of abscisic acid (ABA) signaling; modulates dehydration stress response pathways.Drought toleranceOgata et al. [77].
RiceSRL1, SRL2Control of leaf rolling by influencing leaf morphology, aiding in water conservation under drought.Drought toleranceLiao et al. [81].
RiceSPL10Regulates trichome (leaf hair) development, which can reduce water loss and improve salt stress adaptation.Salinity toleranceLan et al. [82].
RiceSOS1Encodes a plasma membrane Na⁺/H⁺ antiporter; involved in sodium ion efflux, critical for salt tolerance.Salinity toleranceLu et al. [83].
TomatoHyPRP1Hybrid proline-rich protein; acts as a transmembrane protein associated with multiple stress responses, especially salinity.Salinity toleranceTran et al. [48].
TomatoABIG1Homeodomain-leucine zipper (HD-ZIP) transcription factor involved in ABA-mediated stress response.Salinity toleranceDing et al. [84].
TomatoLBD40Lateral organ boundary domain gene; involved in jasmonic acid (JA) mediated response to environmental stresses.Drought toleranceLiu et al. [85].
TomatoNPR1Encodes the receptor of salicylic acid; key regulator of systemic acquired resistance and drought stress responses.Drought toleranceLi et al. [86].
WheatDREB2, DREB3, ERF3Transcription factors from DREB (dehydration-responsive element binding) and ERF families; modulate expression of drought-responsive genes.Drought toleranceKim et al. [87].
WheatTwo HAG homologsHistone acetyltransferase-related genes; modulate reactive oxygen species (ROS) signaling and stress gene activation.Salinity toleranceZheng et al. [88].
Maizeabh2Abscisic acid 8′-hydroxylase; regulates stomatal opening and ABA catabolism, influencing drought response.Drought toleranceLiu et al. [89].
MaizeHKT1High-affinity potassium transporter 1; regulates Na⁺ exclusion from shoots and maintains ion homeostasis under salinity.Salinity toleranceZhang et al. [90].
CottonAITR genes (e.g., DPA4, SOD7)AITR family genes regulate plant architecture and seed size; modulate stress responses, including salt tolerance.Salinity toleranceWang et al. [91].
BarleyHVP10Involved in Na+ sequestration in the tonoplast.Salinity toleranceFu et al. [92].
SoybeanNHX5Na+ /H+ exchanger (NHX) transmembrane proteinSalinity toleranceSun et al. [93].
PumpkinRBOHDNADPH oxidaseSalinity toleranceHuang et al. [94].

Table 1.

Significant CRISPR/Cas9 mediated drought and salinity tolerance enhancement.

Source: Compiled by the authors.

Further, pangenome analysis, gene stacking, and synthetic biology represent cutting-edge strategies in the development of drought- and salinity-tolerant plants. Pangenome analysis allows for the comprehensive exploration of genetic diversity across cultivated and wild relatives, facilitating the identification of novel alleles associated with osmotic adjustment, ion homeostasis, and stress signaling [95]. These unique alleles can then be targeted for introgression through marker-assisted backcrossing or genome editing to enhance stress resilience. Gene stacking, or pyramiding, involves the combination of multiple genes or quantitative trait loci (QTLs) that regulate different facets of stress response, such as osmoprotectant biosynthesis, antioxidative defense, and ion transport. This approach has been shown to produce crops with broader and more stable tolerance to multiple abiotic stresses [96]. In parallel, synthetic biology offers the potential to engineer entirely novel regulatory circuits and metabolic pathways not found in nature. For instance, the construction of synthetic osmoregulatory networks or stress-inducible gene modules in model plants has demonstrated enhanced adaptation under extreme environmental conditions [97]. While still largely in the experimental phase, these integrative technologies significantly expand the toolkit for developing climate-resilient crops and hold promise for future agricultural sustainability.

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5. Practical outcomes of genetic engineering for drought and salt tolerance

Traditional breeding has long enhanced crop resilience by selecting tolerant cultivars through crossbreeding and exploiting natural genetic variability, as seen in India’s development of salt- and drought-tolerant rice [98, 99]. However, this approach is time-intensive and limited by the gene pool’s diversity. In contrast, genetic engineering enables precise and rapid modification of stress-related genes, exemplified by transgenic crops such as Bt cotton and drought-tolerant maize [49100]. Advances like CRISPR-Cas9 further allow targeted, foreign DNA-free edits, as demonstrated in drought- and salt-resistant tomato and rice [101]. While genetic engineering offers speed and specificity, traditional breeding garners broader acceptance. Integrating both strategies with genomics-assisted tools presents a robust pathway to sustainable agricultural resilience [102].

5.1 Successful GM and transgenic crops

The intensifying impacts of climate change, notably water scarcity and soil salinization, have propelled the development of genetically engineered crops with enhanced stress tolerance [103]. Biotechnological strategies aimed at increasing salt tolerance and water-use efficiency (WUE) are crucial for maintaining crop productivity under adverse conditions [104]. Table 2 outlines various significant experiments on drought- and salt-tolerant crops. Drought-tolerant maize (MON 87460), engineered with the Bacillus subtilis cspB gene, enhances WUE by stabilizing proteins and photosynthetic structures under water deficit [117]. Bt cotton, initially designed for pest resistance, also improves drought tolerance via better stomatal regulation and root architecture [118]. Transgenic rice expressing AtNHX1 facilitates vacuolar Na+ sequestration, maintaining ionic balance under salinity stress [119], while tomatoes overexpressing SlNCED1 increase abscisic acid, promoting osmotic balance and stomatal closure [120]. In cotton, transgenic stacking of HVA1 and DREB enhances osmotic adjustment and photosynthetic efficiency under drought, achieving up to 30% higher lint yields while maintaining fiber quality [121, 122, 123]. These traits demonstrate the value of combining biotic and abiotic resistance [124], though biosafety, regulatory approval, and public acceptance remain essential [125]. CRISPR/Cas9-based editing of ARGOS8 in maize reduces ethylene sensitivity, delaying senescence and boosting biomass without yield penalties [126, 127], exemplifying integrated molecular strategies for climate-resilient agriculture [128].

CropGenotypes studiedNumber of genotypesNature of salinity stressorNature of studyParameters studiedTrait targetedMethod usedKey outcomesReference
Bt CottonBt cotton hybrids3SalinityField trials across IndiaYield, pest resistanceSalt tolerance and pest resistanceGenetic modification (Bt gene insertion)Bt cotton showed increased yield and reduced pesticide use under saline conditions.Qaim [105].
Drought-resistant maize33D53AM, conventional hybrid; PAM, DT hybrid2Drought and salinityRegional-scale simulation studyYield, water-use efficiencyDrought and salinity toleranceAPSIM-Maize modelingDT hybrids showed improved yield and water savings under deficit irrigation.Su et al. [106].
Transgenic riceVarious transgenic linesMultipleDrought and salinityGreenhouse and field trialsGrowth parameters, ion content, and yieldSalinity toleranceGenetic transformationTransgenic lines exhibited improved growth and yield under saline conditions.Ashraf and Akram [107], Joshi et al. [108]
Salt-tolerant AcaciaVarious Acacia speciesMultipleSalinityField trialsSurvival rate, growth parametersSalinity toleranceField evaluationIdentified species with higher survival and growth under saline conditions.Niknam and McComb [109].
BarleyBH 19-15, BH 19-49, BH 19-02, BH 946, BH 20-02, RD 2794, BH 20-36, BH 19-52, BH 20-38, BH 19-44, BH 20-40, BH 20-09, BH 19-13, DWRB 9114Natural soil salinity (EC 4 dS/m)Field trialYield components, stress indices (SSI, TOL, STI, etc.)Salinity toleranceField evaluation with stress indicesIdentified genotypes with superior performance under salinity stress.Kumar et al. [110].
TomatoVarious cultivarsMultipleDrought and salinityControlled environmentGrowth parameters, ion content, and yieldSalinity and drought tolerancePhysiological and agronomic assessmentsCertain cultivars maintained better growthand yield under salinity stress.Maryum et al. [111], Murtaza et al. [112].
WheatKharchia-65, KRL-210, HD-2329, WH-5424200 mM NaClControlled environmentPlant height, tiller number, leaf senescence, and chlorophyll contentSalinity tolerancePhysiological and biochemical analysesKharchia-65 and KRL-210 exhibited higher tolerance with less reduction in growth parameters.Kumar et al. [113].
WheatGW503, DBW17,NI5643, NW1014, PBW65, PBW502, DBW187, DBW222, DBW303, NW1076, HD1941, HD2009, HD3086, GW89, K916220EC 4.02 dS/m (saline-sodic field conditions)Field trialYield components, ion content, proline accumulation, and antioxidant activitySalinity toleranceField evaluation with biochemical assaysIdentified tolerant genotypes with higher antioxidant activity and better ion balance.Patwa et al. [114].
RiceHKN, XD2H, HHZ, DJWJ, JFX, NSIC Rc2946Saline field conditionsField trialYield and yield componentsSalinity toleranceAgronomic evaluationTolerant genotypes maintained higher yield under salinity stress.Xu et al. [115].
CottonZ9807, Z0228, Z7526,Z0710, Z7514, Z1910, Z7516,Z0102, Z7780, Z9648, Z961211SalinitySeedling stage evaluationSodium and potassium ion content, salt tolerance indexSalt toleranceMorphological and physiological assessmentsIdentified genotypes with higher salt tolerance based on ion content and growth parameters.Sikder et al. [116].

Table 2.

Significant transgenic experiments to develop drought and salinity tolerance in different crop varieties.

Source: Compiled by the authors.

5.2 Field performance and adoption of genetically modified (GM) crops

Genetically modified (GM) crops offer several agronomic and nutritional benefits, including herbicide tolerance, insect resistance, abiotic stress tolerance, disease resistance, and enhanced nutritional content [38]. Bt cotton, a leading example, has significantly reduced pesticide use and improved yields and profitability in countries like China and India [129, 130]. Similarly, Bt soybean and Bt maize have achieved effective pest control in North America [131]. GM crops with herbicide tolerance, such as glyphosate-resistant maize and soybean, lower labor costs and soil degradation by minimizing tillage [132]. Nutritionally enhanced GM crops, such as Golden Rice, address deficiencies such as vitamin A shortage [133]. However, public skepticism and regulatory constraints—especially stringent in Europe—hinder broader adoption [134, 135]. While GM crops show exceptional field performance in North and South America, concerns over resistance development, gene flow, and biodiversity impacts continue to shape their global acceptance and future deployment [136].

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6. Comparing breeding and genetic engineering approaches

Traditional plant breeding and genetic engineering are two pivotal strategies for enhancing drought and salinity tolerance in crops. Conventional breeding involves selecting and crossing naturally stress-tolerant varieties to combine beneficial traits. This method has yielded notable successes, such as the development of salt-tolerant rice and wheat lines. However, its effectiveness is limited by the availability of genetic diversity, sexual compatibility barriers, and the complexity of traits such as drought and salinity tolerance, which are often controlled by multiple genes [137, 138]. Moreover, the long breeding cycles and potential for linkage drag make this approach time-consuming and less precise.

In contrast, genetic engineering enables the direct introduction or modification of specific genes associated with stress tolerance, bypassing species barriers. Key advances include the incorporation of genes encoding transcription factors such as DREB, Late Embryogenesis Abundant (LEA) proteins, and ion transporters like NHX1 and HKT1, which have demonstrated enhanced osmotic adjustment, ion homeostasis, and cellular protection under stress conditions [41, 44, 45, 46]. Moreover, using stress-inducible and tissue-specific promoters helps mitigate adverse effects on plant growth by restricting transgene expression to relevant conditions or tissues [139].

While breeding remains vital for integrating multiple traits into elite germplasm, genetic engineering offers complementary precision and speed essential for tackling complex, multigenic stress responses in a changing climate. Table 3 outlines the key distinctions between traditional breeding and genetic engineering approaches in the development of stress-tolerant plants.

CriteriaTraditional breedingGenetic engineeringReference
DefinitionCrossing of organisms with desirable traits through sexual reproduction.Direct manipulation of an organism’s DNA to introduce or alter traits.Acquaah [140], Nicholl [141].
SpeedSlow – often requires multiple generations over several years.Fast–specific traits can be introduced within weeks or months.Acquaah [140], Nicholl [141].
PrecisionLow – involves large segments of DNA, and unintended traits may be inherited.High – allows targeting of specific genes with minimal unintended effects.Acquaah [140], Ladics et al. [142].
Gene sourcesLimited to sexually compatible species.Genes can come from any species (e.g., bacteria, animals, etc.).Acquaah [140], Nicholl [141].
Trait predictabilityLess predictable – influenced by recombination and environment.More predictable – genes are selected and controlled more precisely.Acquaah [140], Nicholl [141].
CostLower upfront costs but higher cumulative costs due to time.Higher R&D and regulatory costs but more efficient in the long run.Acquaah [140], National Academies of Sciences [143].
Regulatory oversightMinimal – often exempt from modern biotech regulations.Strict – requires comprehensive biosafety, health, and environmental evaluations.Acquaah [140], Eckerstorfer et al. [144].
Public perceptionGenerally favorable – seen as “natural” or traditional.Often controversial – concerns about GMOs and unnatural modifications.Acquaah [140], Mueller and Flachs [145].
Notable examplesHybrid corn, drought-tolerant wheat, improved tomatoes via selection.Bt corn, Golden Rice (Vitamin A), herbicide-resistant soybeans, insulin from GM bacteria.Rosero et al. [146], Bagwan et al. [147].
LimitationsSlower progress, limited gene pool, unpredictable outcomes.Ethical debates, high regulation, potential for unintended ecological or health impacts.Acquaah [140], Singer et al. [148].

Table 3.

Outlines the key distinctions between traditional breeding and genetic engineering approaches in developing drought and salinity-stress-tolerant plants.

Source: Compiled by the authors.

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7. Integrating breeding and genetic engineering

The development of stress-resilient crops requires a comprehensive strategy that integrates conventional breeding with advanced genetic engineering methodologies. As illustrated in Table 4, several examples highlight the synergistic use of these approaches in developing drought- and salinity-tolerant plant varieties. Conventional breeding techniques, such as hybridization and selection, continue to play a pivotal role in exploiting naturally occurring genetic diversity within elite germplasm. Nevertheless, the efficiency of these methods is constrained by prolonged breeding cycles and the intricate genetic architecture of abiotic stress tolerance, particularly due to the multigenic nature of traits like drought and salinity resistance [103, 162].

Strategy/ApproachDescriptionExamplesAdvantagesLimitationsReferences
Conventional breedingSelection and hybridization of drought/salt-tolerant genotypes over generations.Drought-tolerant wheat, salt-tolerant rice landraces.Widely accepted; uses natural diversity.Time-consuming; limited gene pool; complex traits hard to stabilize.Collins et al. [149], Munns and Gilliham [150].
Marker-assisted selection (MAS)Use of molecular markers linked to QTLs for stress tolerance.QTLs for salt tolerance in rice (Saltol), drought QTLs in maize.Speeds up breeding; improves precision.Still constrained by natural variation; expensive for polygenic traits.Raj and Nadarajah [151].
Transgenic approachesIntroduction of stress-tolerance genes (e.g., transcription factors, transporters).DREB1A, AtNHX1, HKT1, P5CS in rice, tomato, and maize.Enables introgression of novel genes; stress-specific expression.Regulatory hurdles; public concerns; off-target effects.Roy et al. [152], Zhang and Blumwald, [153], Bhatnagar-Mathur et al. [7].
CRISPR/Cas9 genome editingPrecise editing of native stress-response genes without introducing foreign DNA.Editing OsRR22 for salt tolerance; ARGOS8 in maize for drought.High precision; avoids transgenic classification in some countries.Regulatory ambiguity; potential off-targets.Shi et al. [76], Zhang et al. [47], Waltz [154].
Gene pyramidingStacking of multiple genes/QTLs conferring different aspects of tolerance.Combining DREB, LEA, and ion transporter genes.Broader, more durable stress tolerance.Complexity in regulation and expression balance.Tester and Langridge [155].
Speed breeding + CRISPRRapid generation cycles with simultaneous genome editing.Used in wheat and tomato to accelerate CRISPR-based trait introgression.Significantly shortens time from lab to field.Requires infrastructure; currently optimized for select crops.Watson et al. [156], Hickey et al. [157].
Phenotyping and genomics integrationUse of high-throughput phenotyping + genome-wide association studies (GWAS).Identifying novel alleles for osmotic stress resilience in rice.Precision trait mapping; enables genotype-phenotype linkage.High technical and data demands; phenotyping under field stress is difficult.Varshney et al. [158], Tardieu et al. [159].
Synthetic biology approachesDesigning novel biosynthetic pathways or regulatory networks for stress resilience.Engineering synthetic osmoregulatory circuits in model plants.Expands beyond natural gene limitations.Still largely experimental; complex regulatory approval.Liu and Stewart [160], Schaumberg et al. [161].

Table 4.

An account of the prominent studies on breeding and genetic engineering together for drought and salinity tolerance in crops.

Source: Compiled by the authors.

Recent advances in genome editing, particularly CRISPR/Cas9, have enabled precise, targeted modifications of stress-responsive genes involved in ionic homeostasis and osmoprotectant synthesis, facilitating the rapid development of superior allelic variants [163]. CRISPR-edited rice and maize lines have demonstrated enhanced physiological responses under stress, including up to 30% improved water-use efficiency and a 25% reduction in sodium accumulation compared to non-edited counterparts [50, 114].

Integrating genetic engineering with hybrid breeding is further strengthened by high-throughput phenotyping and genomic prediction models, which help assess allele performance across diverse genotypes [164]. Pangenomic analyses of wild relatives provide access to untapped alleles for traits like osmotic adjustment, which can be fine-mapped and introgressed via marker-assisted backcrossing or targeted editing [95].

Collaborative platforms uniting public and private sectors enable shared phenotyping protocols and germplasm development, while machine learning algorithms optimize hybrid × gene-editing strategies. Together, these integrated methodologies have boosted drought tolerance gains by up to 40% in key crops such as wheat and cotton [165].

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8. Challenges and considerations in the deployment of genetically modified crops

The development of genetically modified (GM) crops with enhanced tolerance to drought and salinity represents a promising strategy to strengthen global food security amid intensifying environmental stresses. Engineered through sophisticated molecular technologies, these crops offer precise interventions to improve plant resilience under adverse conditions. However, their widespread adoption is accompanied by several ecological, regulatory, and socio-economic challenges. A major ecological concern involves the potential for transgene flow to wild relatives, which may unintentionally introduce novel traits into natural ecosystems, thereby disrupting ecological balance and affecting non-target organisms [166, 167]. Furthermore, interactions between GM crops and various biotic components—such as pests, pollinators, and beneficial soil microbes—require rigorous ecological risk assessments to evaluate long-term environmental impacts. It is also critical to recognize the disparity between laboratory success and real-world performance, as many transgenic lines that exhibit stress tolerance under controlled conditions encounter limitations in field environments due to complex environmental interactions and regulatory constraints. Several notable examples illustrating these challenges are summarized in Table 5.

CropTransgene(s)Laboratory OutcomesField PerformanceReference
Wheat (HB4)HaHB4 (from sunflower)Enhanced drought tolerance; delayed senescenceApproved in Argentina (2020), Brazil (2021), USA (2022); increased yield under droughtRibichich et al. [168], Raineri et al. [169].
Soybean (HB4)HaHB4 (from sunflower)Improved drought toleranceFour percent average yield increase; up to 10.5% under high temperature and drought; approved in China (2022)Ribichich et al. [168].
SoybeanAhBADH (from Atriplex hortensis)Enhanced salt tolerance; stable gene expressionLines TL2 and TL7 showed improved agronomic traits under 300 mM NaCl; under biosafety assessmentYu et al. [170].
WheatMDAR1 (from Arabidopsis)Improved salt stress toleranceField trials in Egypt demonstrated enhanced performance under salinity stressAbdelsattar et al. [171].
TomatoOverexpression of the salt-tolerance geneThrived in soils 50 times saltier than normalNot yet commercially viable; projected 3+ years to marketGuo et al. [172].
Wheat (Kharchia 65)Traditional breeding (Kharchia Local × rust-resistant lines)High salt toleranceUsed as a standard for salt tolerance in wheat; yields 10–20 Q/haSathee et al. [173].

Table 5.

An account of laboratory success and practical field application, where many transgenic crops face environmental and regulatory screening.

Source: Compiled by the authors.

On the regulatory front, global frameworks remain fragmented. Countries differ significantly in how they classify and manage GMOs, particularly with the advent of gene-editing technologies such as CRISPR-Cas9. In the United States, a relatively permissive regulatory approach distinguishes between transgenic organisms and gene-edited crops lacking foreign DNA, often exempting the latter from stringent oversight and thereby facilitating their commercial release [174]. Conversely, the European Union adopts a more cautious stance. The European Court of Justice ruled in 2018 that all gene-edited organisms fall under existing GMO legislation, irrespective of the presence of foreign DNA [175]. In contrast, countries such as Argentina, Brazil, and Japan have adopted more nuanced frameworks, exempting CRISPR-edited crops from GMO regulations when modifications mimic natural mutations and no transgenes are introduced [176].

Beyond regulation, social acceptance remains a challenge. Despite scientific consensus on GM crop safety, public skepticism persists due to perceived health risks, environmental impacts, and ethical concerns [134]. Addressing these issues requires transparent governance, robust public engagement, and science-based communication strategies. Economically, the high costs associated with developing GM crops—including investment in gene-editing tools, rigorous testing, regulatory approvals, and necessary infrastructure—can restrict access for smallholder farmers, particularly in developing regions [177]. This economic barrier risks exacerbating existing inequalities in agricultural productivity and technological adoption [178].

Thus, while GM crops and genome-edited technologies hold substantial potential to enhance crop resilience and agricultural sustainability, their broader success hinges on the implementation of integrative strategies that balance innovation with ecological safety, regulatory coherence, equitable access, and public trust.

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9. Future prospects

The escalating impacts of climate change and the need to sustain a growing global population have highlighted the urgency of developing drought- and salt-tolerant crops. While traditional breeding has contributed to crop resilience, its slow pace and difficulty in combining multiple traits limit its effectiveness. The integration of biotechnology, particularly genetic engineering, has significantly enhanced breeding precision by enabling the targeted incorporation of genes associated with drought and salt tolerance [179]. Innovations such as CRISPR-Cas9 have further refined genome editing, allowing for precise trait introduction with minimal off-target effects compared to conventional methods [71]. These advances are pivotal in addressing climate-induced challenges and ensuring food security. Additionally, precision agriculture—combining biotechnology with data-driven tools such as remote sensing and soil moisture sensors—enables site-specific crop management, improving yield and sustainability [179]. The rapid development of gene-editing technologies and gene synthesis platforms also facilitates the design of stress-resilient crops tailored to local environments, ushering in an era of personalized agriculture [180]. Together, these integrated approaches offer transformative potential for cultivating climate-resilient crops and securing global food systems in an uncertain environmental future.

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10. Conclusion

The escalating impacts of climate change, including intensified drought and soil salinization, present significant threats to agricultural sustainability and global food security. This review examines the physiological, molecular, and genetic mechanisms underlying plant responses to abiotic stress and assesses the effectiveness of both conventional breeding and modern genetic engineering in developing drought- and salt-tolerant crops. Traditional breeding, though widely utilized, is hindered by the slow integration of traits, polygenic complexity, and limited genetic diversity. In contrast, genetic engineering—particularly transgenic approaches and CRISPR/Cas9 genome editing—has enabled precise modification of key stress-responsive genes, enhancing water-use efficiency, ion regulation, and antioxidative responses. Successful examples include drought-tolerant maize (MON 87460) and salinity-tolerant rice expressing AtNHX1. However, the broader adoption of genetically modified crops remains challenged by technical, regulatory, and ethical concerns, such as rigorous biosafety protocols, public resistance, and limited access in low-resource regions. The review underscores the promise of integrative strategies combining traditional and molecular techniques, supported by genomics, high-throughput phenotyping, and predictive modeling, to accelerate breeding outcomes. As climate pressures intensify, future efforts must prioritize interdisciplinary collaboration, transparent regulation, and equitable innovation. Ultimately, a harmonized approach merging genetic precision with conventional resilience offers the most sustainable path toward climate-resilient agriculture.

Acknowledgments

The authors are grateful to the Hon’ble Vice Chancellor of Raiganj University and the Hon’ble Principal, Hiralal Mazumdar College for Women, India, for providing the necessary facilities. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Conflict of interest

The authors declare no conflict of interest.

References

  1. 1. Boyer JS. Plant productivity and environment. Science. 1982;218(4571):443-448
  2. 2. Munns R, Tester M. Mechanisms of salinity tolerance. Annual Review of Plant Biology. 2008;59(1):651-681
  3. 3. Khondoker M, Mandal S, Gurav R, Hwang S. Freshwater shortage, salinity increase, and global food production: A need for sustainable irrigation water desalination—A scoping review. Earth. 4 Apr 2023;4(2):223-240
  4. 4. Lobell DB, Field CB. Global scale climate–crop yield relationships and the impacts of recent warming. Environmental Research Letters. 2007;2(1):014002
  5. 5. Ashraf MF, Foolad MR. Roles of glycine betaine and proline in improving plant abiotic stress resistance. Environmental and Experimental Botany. 2007;59(2):206-216
  6. 6. Tuberosa R, Salvi S. Genomics-based approaches to improve drought tolerance of crops. Trends in Plant Science. 2006;11(8):405-412
  7. 7. Bhatnagar-Mathur P, Vadez V, Sharma KK. Transgenic approaches for abiotic stress tolerance in plants: Retrospect and prospects. Plant Cell Reports. 2008;27:411-424
  8. 8. Schroeder JI, Allen GJ, Hugouvieux V, Kwak JM, Waner D. Guard cell signal transduction. Annual Review of Plant Biology. 2001;52(1):627-658
  9. 9. Uga Y, Sugimoto K, Ogawa S, Rane J, Ishitani M, Hara N, et al. Control of root system architecture by deeper rooting 1 increases rice yield under drought conditions. Nature Genetics. 2013;45(9):1097-1102
  10. 10. Shabala S, Cuin TA. Potassium transport and plant salt tolerance. Physiologia Plantarum. 2008;133(4):651-669
  11. 11. Mittler R, Zandalinas SI, Fichman Y, Van Breusegem F. Reactive oxygen species signalling in plant stress responses. Nature Reviews Molecular Cell Biology. 2022;23(10):663-679
  12. 12. Flexas J, Medrano H. Drought-inhibition of photosynthesis in C3 plants: Stomatal and non-stomatal limitations revisited. Annals of Botany. 2002;89(2):183-189
  13. 13. Sinha A, Berkelhammer M, Stott L, Mudelsee M, Cheng H, Biswas J. The leading mode of Indian summer monsoon precipitation variability during the last millennium. Geophysical Research Letters. 2011;38(15):1-5
  14. 14. Nakashima K, Yamaguchi-Shinozaki K, Shinozaki K. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold, and heat. Frontiers in Plant Science. 2014;5:170
  15. 15. Cutler SR, Rodriguez PL, Finkelstein RR, Abrams SR. Abscisic acid: Emergence of a core signaling network. Annual Review of Plant Biology. 2010;61(1):651-679
  16. 16. Zhu JK. Abiotic stress signaling and responses in plants. Cell. 2016;167(2):313-324
  17. 17. Song J, Price DJ, Guvenen F, Bloom N, Von Wachter T. Firming up inequality. The Quarterly Journal of Economics. 2019;134(1):1-50
  18. 18. Kim KH, Kabir E, Kabir S. A review on the human health impact of airborne particulate matter. Environment International. 2015;74:136-143
  19. 19. Al-Tawaha AR, Odat N, Benkeblia N, Kerkoub N, Labidi Z, Boumendjel M, et al. Breeding crops for tolerance to salinity, heat, and drought. Climate Change and Agriculture: Perspectives, Sustainability and Resilience. 18 Nov 2022:95-110
  20. 20. Ashraf M, Foolad MR. Crop breeding for salt tolerance in the era of molecular markers and marker-assisted selection. Plant Breeding. 2013;132(1):10-20
  21. 21. Kumar M, Prusty MR, Pandey MK, Singh PK, Bohra A, Guo B, et al. Application of CRISPR/Cas9-mediated gene editing for abiotic stress management in crop plants. Frontiers in Plant Science. 2023;14:1157678
  22. 22. Dwivedi SL, Ceccarelli S, Blair MW, Upadhyaya HD, Are AK, Ortiz R. Landrace germplasm for improving yield and abiotic stress adaptation. Trends in Plant Science. 2016;21(1):31-42
  23. 23. Zafar SA, Zaidi SS, Gaba Y, Singla-Pareek SL, Dhankher OP, Li X, et al. Engineering abiotic stress tolerance via CRISPR/Cas-mediated genome editing. Journal of Experimental Botany. 2020;71(2):470-479
  24. 24. Prasanna BM, Hossain F, Lal R. Climate-resilient agriculture: Principles, approaches and challenges. Journal of Experimental Botany. 2020;71(15):4517-4525
  25. 25. Hafeez U, Ali M, Hassan SM, Akram MA, Zafar A. Advances in breeding and engineering climate-resilient crops: A comprehensive review. International Journal of Research and Advances in Agricultural Sciences. 2023;2(2):85-99
  26. 26. Venuprasad R, Dalid CO, Del Valle M, Zhao D, Espiritu M, Sta Cruz MT, et al. Identification and characterization of large-effect quantitative trait loci for grain yield under lowland drought stress in rice using bulk-segregant analysis. Theoretical and Applied Genetics. 2009;120:177-190
  27. 27. Sanghvi GV, Dave GS. Molecular markers in plant biotechnology. In: Plant Biotechnology. Vol. 1. Florida: Apple Academic Press; 2017. pp. 415-453
  28. 28. Sahi C, Singh A, Kumar K, Blumwald E, Grover A. Salt stress response in rice: Genetics, molecular biology, and comparative genomics. Functional & Integrative Genomics. 2006;6:263-284
  29. 29. Walia H, Wilson C, Zeng L, Ismail AM, Condamine P, Close TJ. Genome-wide transcriptional analysis of salinity stressed japonica and indica rice genotypes during panicle initiation stage. Plant Molecular Biology. 2007;63:609-623
  30. 30. Marino R, Ponnaiah M, Krajewski P, Frova C, Gianfranceschi L, Pè ME, et al. Addressing drought tolerance in maize by transcriptional profiling and mapping. Molecular Genetics and Genomics. 2009;281:163-179
  31. 31. Pandit A, Rai V, Bal S, Sinha S, Kumar V, Chauhan M, et al. Combining QTL mapping and transcriptome profiling of bulked RILs for identification of functional polymorphism for salt tolerance genes in rice (Oryza sativa L.). Molecular Genetics and Genomics. 2010;284:121-136
  32. 32. Huang D, Wu W, Abrams SR, Cutler AJ. The relationship of drought-related gene expression in Arabidopsis thaliana to hormonal and environmental factors. Journal of Experimental Botany. 2008;59(11):2991-3007
  33. 33. Seki M, Narusaka M, Ishida J, Nanjo T, Fujita M, Oono Y, et al. Monitoring the expression profiles of 7000 Arabidopsis genes under drought, cold and high-salinity stresses using a full-length cDNA microarray. The Plant Journal. 2002;31(3):279-292
  34. 34. Tanksley SD, Nelson JC. Advanced backcross QTL analysis: A method for the simultaneous discovery and transfer of valuable QTLs from unadapted germplasm into elite breeding lines. Theoretical and Applied Genetics. 1996;92:191-203
  35. 35. Ammar MH, Pandit A, Singh RK, Sameena S, Chauhan MS, Singh AK, et al. Mapping of QTLs controlling Na+, K+ and CI− ion concentrations in salt tolerant indica rice variety CSR27. Journal of Plant Biochemistry and Biotechnology. 2009;18:139-150
  36. 36. Rauf S, Al-Khayri JM, Zaharieva M, Monneveux P, Khalil F. Breeding strategies to enhance drought tolerance in crops. In: Advances in Plant Breeding Strategies: Agronomic, Abiotic and Biotic Stress Traits. Cham: Springer; 2016. pp. 397-445
  37. 37. Griffiths AJ, Wessler SR, Lewontin RC, Gelbart WM, Suzuki DT, Miller JH. Introduction to Genetic Analysis. 8th (Ed.). New York [Internet]: Freeman WH; 2005
  38. 38. Kumar K, Gambhir G, Dass A, Tripathi AK, Singh A, Jha AK, et al. Genetically modified crops: Current status and future prospects. Planta. 2020;251(4):91
  39. 39. Ashraf M, Athar HR, Harris PJ, Kwon TR. Some prospective strategies for improving crop salt tolerance. Advances in Agronomy. 2008;97:45-110
  40. 40. Fageria NK, Stone LF, Santos AB. Breeding for salinity tolerance. In: Plant Breeding for Abiotic Stress Tolerance. Berlin, Heidelberg: Springer; 2012. pp. 103-122
  41. 41. Banerjee A, Roychoudhury A. Group II late embryogenesis abundant (LEA) proteins: Structural and functional aspects in plant abiotic stress. Plant Growth Regulation. 2016;79:1-7
  42. 42. Haghpanah M, Hashemipetroudi S, Arzani A, Araniti F. Drought tolerance in plants: Physiological and molecular responses. Plants. 2024;13(21):2962
  43. 43. KhokharVoytas A, Shahbaz M, Maqsood MF, Zulfiqar U, Naz N, Iqbal UZ, et al. Genetic modification strategies for enhancing plant resilience to abiotic stresses in the context of climate change. Functional & Integrative Genomics. 2023;23(3):283
  44. 44. de Paiva Rolla AA, de Fátima Corrêa Carvalho J, Fuganti-Pagliarini R, Engels C, Do Rio A, Marin SR, et al. Phenotyping soybean plants transformed with rd29A: AtDREB1A for drought tolerance in the greenhouse and field. Transgenic Research. 2014;23:75-87
  45. 45. Dave A, Agarwal P, Agarwal PK. Mechanism of high affinity potassium transporter (HKT) towards improved crop productivity in saline agricultural lands. 3 Biotech. 2022;12(2):51
  46. 46. Paul S, Roychoudhury A. Transgenic plants for improved salinity and drought tolerance. In: Biotechnologies of Crop Improvement, Volume 2: Transgenic Approaches. Cham: Springer; 2018. pp. 141-181
  47. 47. Zhang A, Liu Y, Wang F, Li T, Chen Z, Kong D, et al. Enhanced rice salinity tolerance via CRISPR/Cas9-targeted mutagenesis of the OsRR22 gene. Molecular Breeding. 2019;39:47
  48. 48. Tran MT, Doan DTH, Kim J, Song YJ, Sung YW, Das S, et al. CRISPR/Cas9-based precise excision of SlHyPRP1 domain (s) to obtain salt stress-tolerant tomato. Plant Cell Reports. 2021;40:999-1011
  49. 49. Liang C. Genetically modified crops with drought tolerance: Achievements, challenges, and perspectives. In: Drought Stress Tolerance in Plants, Vol. 2: Molecular and Genetic Perspectives. Cham: Springer; 2016. pp. 531-547
  50. 50. Huang Z, Zhong XJ, He J, Jin SH, Guo HD, Yu XF, et al. Genome-wide identification, characterization, and stress-responsive expression profiling of genes encoding LEA (late embryogenesis abundant) proteins in Moso bamboo (Phyllostachys edulis). PLoS One. 2016;11(11):e0165953
  51. 51. Liang Y, Xiong Z, Zheng J, Xu D, Zhu Z, Xiang J, et al. Genome-wide identification, structural analysis and new insights into late embryogenesis abundant (LEA) gene family formation pattern in Brassica napus. Scientific Reports. 2016;6(1):24265
  52. 52. Cheng Z, Targolli J, Huang X, Wu R. Wheat LEA genes, PMA80 and PMA1959, enhance dehydration tolerance of transgenic rice (Oryza sativa L.). Molecular Breeding. 2002;10:71-82
  53. 53. Yu J, Lai Y, Wu X, Wu G, Guo C. Overexpression of OsEm1 encoding a group I LEA protein confers enhanced drought tolerance in rice. Biochemical and Biophysical Research Communications. 2016;478(2):703-709
  54. 54. Ganguly M, Datta K, Roychoudhury A, Gayen D, Sengupta DN, Datta SK. Overexpression of Rab16A gene in indica rice variety for generating enhanced salt tolerance. Plant Signaling & Behavior. 2012;7(4):502-509
  55. 55. Wang H, Wu Y, Yang X, Guo X, Cao X. SmLEA2, a gene for late embryogenesis abundant protein isolated from salvia miltiorrhiza, confers tolerance to drought and salt stress in Escherichia coli and S. Miltiorrhiza. Protoplasma. 2017;254:685-696
  56. 56. Babu RC, Zhang J, Blum A, Ho TH, Wu R, Nguyen HT. HVA1, a LEA gene from barley confers dehydration tolerance in transgenic rice (Oryza sativa L.) via cell membrane protection. Plant Science. 2004;166(4):855-862
  57. 57. Ke YT, Lu CA, Wu SJ, Yeh CH. Characterization of rice group 3 LEA genes in developmental stages and under abiotic stress. Plant Molecular Biology Reporter. 2016;34:1003-1015
  58. 58. Sharma A, Kumar D, Kumar S, Rampuria S, Reddy AR, Kirti PB. Ectopic expression of an atypical hydrophobic group 5 LEA protein from wild peanut, Arachis diogoi confers abiotic stress tolerance in tobacco. PLoS One. 2016;11(3):e0150609
  59. 59. Malik MK, Slovin JP, Hwang CH, Zimmerman JL. Modified expression of a carrot small heat shock protein gene, Hsp17. 7, results in increased or decreased thermotolerance. The Plant Journal. 1999;20(1):89-99
  60. 60. Katiyar-Agarwal S, Agarwal M, Grover A. Heat-tolerant basmati rice engineered by over-expression of hsp101. Plant Molecular Biology. 2003;51:677-686
  61. 61. Sun W, Bernard C, Van De Cotte B, Van Montagu M, Verbruggen N. At-HSP17. 6A, encoding a small heat-shock protein in Arabidopsis, can enhance osmotolerance upon overexpression. The Plant Journal. 2001;27(5):407-415
  62. 62. Wang Y, Ying J, Kuzma M, Chalifoux M, Sample A, McArthur C, et al. Molecular tailoring of farnesylation for plant drought tolerance and yield protection. The Plant Journal. 2005;43(3):413-424
  63. 63. Gharsallah C, Fakhfakh H, Grubb D, Gorsane F. Effect of salt stress on ion concentration, proline content, antioxidant enzyme activities and gene expression in tomato cultivars. AoB Plants. 2016;8:plw055
  64. 64. Rahneshan Z, Nasibi F, Moghadam AA. Effects of salinity stress on some growth, physiological, biochemical parameters and nutrients in two pistachio (Pistacia vera L.) rootstocks. Journal of Plant Interactions. 2018;13:73-82
  65. 65. Pan T, Liu M, Kreslavski VD, Zharmukhamedov SK, Nie C, Yu M, et al. Non-stomatal limitation of photosynthesis by soil salinity. Critical Reviews in Environmental Science and Technology. 2021;51:791-825
  66. 66. Yue Y, Zhang M, Zhang J, Duan L, Li Z. SOS1 gene overexpression increased salt tolerance in transgenic tobacco by maintaining a higher K+/Na+ ratio. Journal of Plant Physiology. 2012;169(3):255-261
  67. 67. Mian A, Oomen RJ, Isayenkov S, Sentenac H, Maathuis FJ, Véry AA. Over-expression of an Na+−and K+-permeable HKT transporter in barley improves salt tolerance. The Plant Journal. 2011;68:468-479
  68. 68. Yue E, Cao H, Liu B. OsmiR535, a potential genetic editing target for drought and salinity stress tolerance in Oryza sativa. Plants. 2020;9:1337
  69. 69. Kim S-T, Choi M, Bae S-J, Kim J-S. The functional association of ACQOS/VICTR with salt stress resistance in Arabidopsis thaliana was confirmed by CRISPR-mediated mutagenesis. International Journal of Molecular Sciences. 2021;22:11389
  70. 70. Bhat JA, Deshmukh R, Zhao T, Patil G, Deokar A, Shinde S, et al. Harnessing high-throughput phenotyping and genotyping for enhanced drought tolerance in crop plants. Journal of Biotechnology. 2020;324:248-260
  71. 71. Li X, Xu S, Fuhrmann-Aoyagi MB, Yuan S, Iwama T, Kobayashi M, et al. CRISPR/Cas9 technique for temperature, drought, and salinity stress responses. Current Issues in Molecular Biology. 2022;44(6):2664-2682
  72. 72. Zhao Y, Zhang C, Liu W, Gao W, Liu C, Song G, et al. An alternative strategy for targeted gene replacement in plants using a dual-sgRNA/Cas9 design. Scientific Reports. 2016;6:23890
  73. 73. Osakabe Y, Watanabe T, Sugano SS, Ueta R, Ishihara R, Shinozaki K, et al. Optimization of CRISPR/Cas9 genome editing to modify abiotic stress responses in plants. Scientific Reports. 2016;6:26685
  74. 74. Park J-J, Dempewolf E, Zhang W, Wang Z-Y. RNA-guided transcriptional activation via CRISPR/dCas9 mimics overexpression phenotypes in Arabidopsis. PLoS One. 2017;12:e0179410
  75. 75. Nuñez-Muñoz L, Vargas-Hernández B, Hinojosa-Moya J, Ruiz-Medrano R, Xoconostle-Cázares B. Plant drought tolerance provided through genome editing of the trehalase gene. Plant Signaling & Behavior. 2021;16:1877005
  76. 76. Shi J, Gao H, Wang H, Lafitte HR, Archibald RL, Yang M, et al. ARGOS 8 variants generated by CRISPR-Cas9 improve maize grain yield under field drought stress conditions. Plant Biotechnology Journal. 2017;15:207-216
  77. 77. Ogata T, Ishizaki T, Fujita M, Fujita Y. CRISPR/Cas9-targeted mutagenesis of OsERA1 confers enhanced responses to abscisic acid and drought stress and increased primary root growth under nonstressed conditions in rice. PLoS One. 2020;15:e0243376
  78. 78. He X, Luo X, Wang T, Liu S, Zhang X, Zhu L. GhHB12 negatively regulates abiotic stress tolerance in Arabidopsis and cotton. Environmental and Experimental Botany. 2020;176:104087
  79. 79. Wu J, Yan G, Duan Z, Wang Z, Kang C, Guo L, et al. Roles of the Brassica napus DELLA protein BnaA6. RGA, in modulating drought tolerance by interacting with the ABA signaling component BnaA10. ABF2. Frontiers in Plant Science. 2020;11:577
  80. 80. Zhang H, Zhang J, Wei P, Zhang B, Gou F, Feng Z, et al. The CRISPR/Cas9 system produces specific and homozygous targeted gene editing in rice in one generation. Plant Biotechnology Journal. 2014;12:797-807
  81. 81. Liao S, Qin X, Luo L, Han Y, Wang X, Usman B, et al. CRISPR/Cas9-induced mutagenesis of semi-rolled leaf1, 2 confers curled leaf phenotype and drought tolerance by influencing protein expression patterns and ROS scavenging in rice (Oryza sativa L.). Agronomy. 2019;9:728
  82. 82. Lan T, Zheng Y, Su Z, Yu S, Song H, Zheng X, et al. OsSPL10, a SBP-box gene, plays a dual role in salt tolerance and trichome formation in rice (Oryza sativa L.). G3: Genes, genomes. Genetics. 2019;9(12):4107-4114
  83. 83. Lu Y, Tian Y, Shen R, Yao Q, Wang M, Chen M, et al. Targeted, efficient sequence insertion and replacement in rice. Nature Biotechnology. 2020;38(12):1402-1407
  84. 84. Ding F, Qiang X, Jia Z, Li L, Hu J, Yin M, et al. Knockout of a novel salt responsive gene SlABIG1 enhance salinity tolerance in tomato. Environmental and Experimental Botany. 2022;200:104903
  85. 85. Liu L, Zhang J, Xu J, Li Y, Guo L, Wang Z, et al. CRISPR/Cas9 targeted mutagenesis of SlLBD40, a lateral organ boundaries domain transcription factor, enhances drought tolerance in tomato. Plant Science. 2020;301:110683
  86. 86. Li R, Liu C, Zhao R, Wang L, Chen L, Yu W, et al. CRISPR/Cas9-mediated SlNPR1 mutagenesis reduces tomato plant drought tolerance. BMC Plant Biology. 2019;19:1-3
  87. 87. Kim D, Alptekin B, Budak H. CRISPR/Cas9 genome editing in wheat. Functional & Integrative Genomics. 2018;18:31-41
  88. 88. Zheng M, Lin J, Liu X, Chu W, Li J, Gao Y, et al. Histone acetyltransferase TaHAG1 acts as a crucial regulator to strengthen salt tolerance of hexaploid wheat. Plant Physiology. 2021;186(4):1951-1969
  89. 89. Liu S, Li C, Wang H, Wang S, Yang S, Liu X, et al. Mapping regulatory variants controlling gene expression in drought response and tolerance in maize. Genome Biology. 2020;21:1-22
  90. 90. Zhang M, Cao Y, Wang Z, Wang ZQ, Shi J, Liang X, et al. A retrotransposon in an HKT1 family sodium transporter causes variation of leaf Na+ exclusion and salt tolerance in maize. New Phytologist. 2018;217(3):1161-1176
  91. 91. Wang T, Xun H, Wang W, Ding X, Tian H, Hussain S, et al. Mutation of GmAITR genes by CRISPR/Cas9 genome editing results in enhanced salinity stress tolerance in soybean. Frontiers in Plant Science. 2021;12:779598
  92. 92. Fu L, Wu D, Zhang X, Xu Y, Kuang L, Cai S, et al. Vacuolar H+-pyrophosphatase HVP10 enhances salt tolerance via promoting Na+ translocation into root vacuoles. Plant Physiology. 2022;188(2):1248-1263
  93. 93. Sun T, Ma N, Wang C, Fan H, Wang M, Zhang J, et al. A golgi-localized sodium/hydrogen exchanger positively regulates salt tolerance by maintaining higher K+/Na+ ratio in soybean. Frontiers in Plant Science. 2021;12:638340
  94. 94. Huang Y, Cao H, Yang L, Chen C, Shabala L, Xiong M, et al. Tissue-specific respiratory burst oxidase homolog-dependent H2O2 signaling to the plasma membrane H+-ATPase confers potassium uptake and salinity tolerance in Cucurbitaceae. Journal of Experimental Botany. 2019;70(20):5879-5893
  95. 95. Ullah MA, Abdullah-Zawawi MR, Zainal-Abidin RA, Sukiran NL, Uddin MI, Zainal Z. A review of integrative omic approaches for understanding rice salt response mechanisms. Plants. 2022;11(11):1430
  96. 96. Shailani A, Joshi R, Singla-Pareek SL, Pareek A. Stacking for future: Pyramiding genes to improve drought and salinity tolerance in rice. Physiologia Plantarum. 2021;172(2):1352-1362
  97. 97. Golldack D, Lüking I, Yang O. Plant tolerance to drought and salinity: Stress regulating transcription factors and their functional significance in the cellular transcriptional network. Plant Cell Reports. 2011;30:1383-1391
  98. 98. Swarup S, Cargill EJ, Crosby K, Flagel L, Kniskern J, Glenn KC. Genetic diversity is indispensable for plant breeding to improve crops. Crop Science. 2021;61(2):839-852
  99. 99. Qin H, Li Y, Huang R. Advances and challenges in the breeding of salt-tolerant rice. International Journal of Molecular Sciences. 2020;21(21):8385
  100. 100. Reguera M, Peleg Z, Blumwald E. Targeting metabolic pathways for genetic engineering abiotic stress-tolerance in crops. Biochimica et Biophysica Acta (BBA)-Gene Regulatory Mechanisms. 2012;1819(2):186-194
  101. 101. Erdoğan İ, Cevher-Keskin B, Bilir Ö, Hong Y, Tör M. Recent developments in CRISPR/Cas9 genome-editing technology related to plant disease resistance and abiotic stress tolerance. Biology. 2023;12(7):1037
  102. 102. Hafeez A, Ali B, Javed MA, Saleem A, Fatima M, Fathi A, et al. Plant breeding for harmony between sustainable agriculture, the environment, and global food security: An era of genomics-assisted breeding. Planta. 2023;258(5):97
  103. 103. Fita A, Rodríguez-Burruezo A, Boscaiu M, Prohens J, Vicente O. Breeding and domesticating crops adapted to drought and salinity: A new paradigm for increasing food production. Frontiers in Plant Science. 2015;6:978
  104. 104. Farooq M, Hussain M, Ul-Allah S, Siddique KH. Physiological and agronomic approaches for improving water-use efficiency in crop plants. Agricultural Water Management. 2019;219:95-108
  105. 105. Qaim M. Bt cotton in India: Field trial results and economic projections. World Development. 2003;31(12):2115-2127
  106. 106. Su ZE, Zhao J, Marek TH, Liu K, Harrison MT, Xue Q. Drought tolerant maize hybrids have higher yields and lower water use under drought conditions at a regional scale. Agricultural Water Management. 2022;274:107978
  107. 107. Ashraf M, Akram NA. Improving salinity tolerance of plants through conventional breeding and genetic engineering: An analytical comparison. Biotechnology Advances. 2009;27(6):744-752
  108. 108. Joshi R, Sahoo KK, Singh AK, Anwar K, Pundir P, Gautam RK, et al. Enhancing trehalose biosynthesis improves yield potential in marker-free transgenic rice under drought, saline, and sodic conditions. Journal of Experimental Botany. 2020;71(2):653-668
  109. 109. Niknam SR, McComb J. Salt tolerance screening of selected Australian woody species—A review. Forest Ecology and Management. 2000;139(1-3):1-9
  110. 110. Kumar Y, Devi S, Phougat D, Chaurasia H, Choudhary S. Assessment of barley genotypes for salinity tolerance based on various indices under field condition. Assessment. 2024;12(2):586-598
  111. 111. Maryum Z, Luqman T, Nadeem S, Khan SMUD, Wang B, Ditta A, et al. An overview of salinity stress, mechanism of salinity tolerance and strategies for its management in cotton. Frontiers in Plant Science. 2022;13:907937
  112. 112. Murtaza G, Usman M, Iqbal J, Tahir MN, Elshikh MS, Alkahtani J, et al. The impact of biochar addition on morpho-physiological characteristics, yield and water use efficiency of tomato plants under drought and salinity stress. BMC Plant Biology. 2024;24(1):356
  113. 113. Kumar S, Beena AS, Awana M, Singh A. Physiological, biochemical, epigenetic and molecular analyses of wheat (Triticum aestivum) genotypes with contrasting salt tolerance. Frontiers in Plant Science. 2017;8:1151
  114. 114. Patwa N, Pandey V, Gupta OP, Yadav A, Meena MR, Ram S, et al. Unravelling wheat genotypic responses: Insights into salinity stress tolerance in relation to oxidative stress, antioxidant mechanisms, osmolyte accumulation and grain quality parameters. BMC Plant Biology. 2024;24(1):875
  115. 115. Xu Y, Bu W, Xu Y, Fei H, Zhu Y, Ahmad I, et al. Effects of salt stress on physiological and agronomic traits of rice genotypes with contrasting salt tolerance. Plants. 2024;13(8):1157
  116. 116. Sikder RK, Wang X, Jin D, Zhang H, Gui H, Dong Q, et al. Screening and evaluation of reliable traits of upland cotton (Gossypium hirsutum L.) genotypes for salt tolerance at the seedling growth stage. Journal of Cotton Research. 2020;3:1-13
  117. 117. Ortiz R, Jarvis A, Fox P, Aggarwal PK, Campbell BM. Plant Genetic Engineering, Climate Change and Food Security. Copenhagen, Denmark: CCAFS Working Paper66; 2014
  118. 118. Khan A, Pan X, Najeeb U, Tan DK, Fahad S, Zahoor R, et al. Coping with drought: Stress and adaptive mechanisms, and management through cultural and molecular alternatives in cotton as vital constituents for plant stress resilience and fitness. Biological Research. 2018;51:1-17
  119. 119. Krishnamurthy P, Vishal B, Khoo K, Rajappa S, Loh CS, Kumar PP. Expression of AoNHX1 increases salt tolerance of rice and Arabidopsis, and bHLH transcription factors regulate AtNHX1 and AtNHX6 in Arabidopsis. Plant Cell Reports. 2019;38:1299-1315
  120. 120. Ji K, Kai W, Zhao B, Sun Y, Yuan B, Dai S, et al. SlNCED1 and SlCYP707A2: Key genes involved in ABA metabolism during tomato fruit ripening. Journal of Experimental Botany. 2014;65(18):5243-5255
  121. 121. Chen YS, Lo SF, Sun PK, Lu CA, Ho TH, Yu SM. A late embryogenesis abundant protein HVA 1 regulated by an inducible promoter enhances root growth and abiotic stress tolerance in rice without yield penalty. Plant Biotechnology Journal. 2015;13(1):105-116
  122. 122. Rasheed A, Zhao L, Raza A, Mahmood A, Xing H, Lv X, et al. Role of molecular breeding tools in enhancing the breeding of drought-resilient cotton genotypes: An updated review. Water. 2023;15(7):1377
  123. 123. Nagamalla SS, Alaparthi MD, Mellacheruvu S, Gundeti R, Earrawandla JP, Sagurthi SR. Morpho-physiological and proteomic response of Bt-cotton and non-Bt cotton to drought stress. Frontiers in Plant Science. 2021;12:663576
  124. 124. Kamburova V, Salakhutdinov I, Abdurakhmonov IY. Cotton Breeding in the View of Abiotic and Biotic Stresses: Challenges and Perspectives. London, UK: IntechOpen; 2022
  125. 125. Gupta K, Karihaloo J, Khetarpal R. Biosafety Regulations for GM Crops in Asia-Pacific. Bangkok: Asia-Pacific Consortium on Agricultural Biotechnology, New Delhi and Asia-Pacific Association of Agricultural Research Institutions; 2014. pp. i-xii. 1-60
  126. 126. Cooper M, Gho C, Leafgren R, Tang T, Messina C. Breeding drought-tolerant maize hybrids for the US corn-belt: Discovery to product. Journal of Experimental Botany. 2014;65(21):6191-6204
  127. 127. Sustek-Sánchez F, Rognli OA, Rostoks N, Sõmera M, Jaškūnė K, Kovi MR, et al. Improving abiotic stress tolerance of forage grasses–prospects of using genome editing. Frontiers in Plant Science. 2023;14:1127532
  128. 128. Banga SS, Kang MS. Developing climate-resilient crops. Journal of Crop Improvement. 2 Jan 2014;28(1):57-87
  129. 129. Glover D. Is Bt cotton a pro-poor technology? A review and critique of the empirical record. Journal of Agrarian Change. 2010;10(4):482-509
  130. 130. Balasubramani G, Raghavendra KP, Das J, Kumar R, Santosh HB, Amudha J, et al. Critical evaluation of GM cotton. In: Cotton Precision Breeding. Cham: Springer International Publishing; 2021. pp. 351-410
  131. 131. Meissle M, Romeis J, Bigler F. Bt maize and integrated pest management-a European perspective. Pest Management Science. 2011;67(9):1049-1058
  132. 132. Bonny S. Genetically modified glyphosate-tolerant soybean in the USA: Adoption factors, impacts and prospects. A review. Agronomy for Sustainable Development. 2008;28:21-32
  133. 133. Paine JA, Shipton CA, Chaggar S, Howells RM, Kennedy MJ, Vernon G, et al. Improving the nutritional value of golden rice through increased pro-vitamin a content. Nature Biotechnology. 2005;23(4):482-487
  134. 134. Sadikiel MG. The adoption of genetically modified crops in Africa: The public’s current perception, the regulatory obstacles, and ethical challenges. GM Crops & Food. 2024;15(1):185-199
  135. 135. Lucht JM. Public acceptance of plant biotechnology and GM crops. Viruses. 2015;7(8):4254-4281
  136. 136. Warwick SI, Beckie HJ, Hall LM. Gene flow, invasiveness, and ecological impact of genetically modified crops. Annals of the New York Academy of Sciences. 2009;1168(1):72-99
  137. 137. Gaba Y, Pareek A, Singla-Pareek SL. Raising climate-resilient crops: Journey from the conventional breeding to new breeding approaches. Current Genomics. 2021;22(6):450-467
  138. 138. Turan S, Cornish K, Kumar S. Salinity tolerance in plants: Breeding and genetic engineering. Australian Journal of Crop Science. 2012;6(9):1337-1348
  139. 139. Kummari D, Palakolanu SR, Kishor PK, Bhatnagar-Mathur P, Singam P, Vadez V, et al. An update and perspectives on the use of promoters in plant genetic engineering. Journal of Biosciences. 2020;45:1-24
  140. 140. Acquaah G. Conventional plant breeding principles and techniques. In: Advances in Plant Breeding Strategies: Breeding, Biotechnology and Molecular Tools. Cham: Springer; 2015. pp. 115-158
  141. 141. Nicholl DS. An Introduction to Genetic Engineering. Cambridge: Cambridge University Press; 2023
  142. 142. Ladics GS, Bartholomaeus A, Bregitzer P, Doerrer NG, Gray A, Holzhauser T, et al. Genetic basis and detection of unintended effects in genetically modified crop plants. Transgenic Research. 2015;24:587-603
  143. 143. National Academies of Sciences, Medicine, Division on Earth, Life Studies, Committee on Genetically Engineered Crops, Past Experience, Future Prospects. Genetically Engineered Crops: Experiences and Prospects. Washington, DC: National Academies Press; 2016
  144. 144. Eckerstorfer MF, Grabowski M, Lener M, Engelhard M, Simon S, Dolezel M, et al. Biosafety of genome editing applications in plant breeding: Considerations for a focused case-specific risk assessment in the EU. Biotech. 2021;10(3):10
  145. 145. Mueller NG, Flachs A. Domestication, crop breeding, and genetic modification are fundamentally different processes: Implications for seed sovereignty and agrobiodiversity. Agriculture and Human Values. 2022;39(1):455-472
  146. 146. Rosero A, Granda L, Berdugo-Cely JA, Šamajová O, Šamaj J, Cerkal R. A dual strategy of breeding for drought tolerance and introducing drought-tolerant, underutilized crops into production systems to enhance their resilience to water deficiency. Plants. 2020;9(10):1263
  147. 147. Bagwan JD, Patil SJ, Mane AS, Kadam VV, Vichare S. Genetically modified crops: Food of the future. International Journal of Advanced Biotechnology and Research. 2010;1(1):21-30
  148. 148. Singer SD, Laurie JD, Bilichak A, Kumar S, Singh J. Genetic variation and unintended risk in the context of old and new breeding techniques. Critical Reviews in Plant Sciences. 2021;40(1):68-108
  149. 149. Collins NC, Tardieu F, Tuberosa R. Quantitative trait loci and crop performance under abiotic stress: Where do we stand? Plant Physiology. 2008;147(2):469-486
  150. 150. Munns R, Gilliham M. Salinity tolerance of crops–what is the cost? New Phytologist. 2015;208(3):668-673
  151. 151. Raj SR, Nadarajah K. QTL and candidate genes: Techniques and advancement in abiotic stress resistance breeding of major cereals. International Journal of Molecular Sciences. 2022;24(1):6
  152. 152. Roy SJ, Negrão S, Tester M. Salt resistant crop plants. Current Opinion in Biotechnology. 2014;26:115-124
  153. 153. Zhang HX, Blumwald E. Transgenic salt-tolerant tomato plants accumulate salt in foliage but not in fruit. Nature Biotechnology. 2001;19(8):765-768
  154. 154. Waltz E. Gene-edited CRISPR mushroom escapes US regulation. Nature. 2016;532(7599):293
  155. 155. Tester M, Langridge P. Breeding technologies to increase crop production in a changing world. Science. 2010;327(5967):818-822
  156. 156. Watson A, Ghosh S, Williams MJ, Cuddy WS, Simmonds J, Rey MD, et al. Speed breeding is a powerful tool to accelerate crop research and breeding. Nature Plants. 2018;4(1):23-29
  157. 157. Hickey LT, Hafeez NA, Robinson H, Jackson SA, Leal-Bertioli SC, Tester M, et al. Breeding crops to feed 10 billion. Nature Biotechnology. 2019;37(7):744-754
  158. 158. Varshney RK, Bohra A, Yu J, Graner A, Zhang Q, Sorrells ME. Designing future crops: Genomics-assisted breeding comes of age. Trends in Plant Science. 2021;26(6):631-649
  159. 159. Tardieu F, Simonneau T, Muller B. The physiological basis of drought tolerance in crop plants: A scenario-dependent probabilistic approach. Annual Review of Plant Biology. 2018;69(1):733-759
  160. 160. Liu W, Stewart CN. Plant synthetic biology. Trends in Plant Science. 2015;20(5):309-317
  161. 161. Schaumberg KA, Antunes MS, Kassaw TK, Xu W, Zalewski CS, Medford JI, et al. Quantitative characterization of genetic parts and circuits for plant synthetic biology. Nature Methods. 2016;13(1):94-100
  162. 162. Oladosu Y, Rafii MY, Samuel C, Fatai A, Magaji U, Kareem I, et al. Drought resistance in rice from conventional to molecular breeding: A review. International Journal of Molecular Sciences. 2019;20(14):3519
  163. 163. Shelake RM, Kadam US, Kumar R, Pramanik D, Singh AK, Kim JY. Engineering drought and salinity tolerance traits in crops through CRISPR-mediated genome editing: Targets, tools, challenges, and perspectives. Plant Communications. 2022;3(6):1-27
  164. 164. Moreira FF, Oliveira HR, Volenec JJ, Rainey KM, Brito LF. Integrating high-throughput phenotyping and statistical genomic methods to genetically improve longitudinal traits in crops. Frontiers in Plant Science. 2020;11:681
  165. 165. Sun L, Lai M, Ghouri F, Nawaz MA, Ali F, Baloch FS, et al. Modern plant breeding techniques in crop improvement and genetic diversity: From molecular markers and gene editing to artificial intelligence—A critical review. Plants. 2024;13(19):2676
  166. 166. Lu BR, Yang C. Gene flow from genetically modified rice to its wild relatives: Assessing potential ecological consequences. Biotechnology Advances. 2009;27(6):1083-1091
  167. 167. Pilson D, Prendeville HR. Ecological effects of transgenic crops and the escape of transgenes into wild populations. Annual Review of Ecology, Evolution, and Systematics. 15 Dec 2004;35(1):149-174
  168. 168. Ribichich KF, Chiozza M, Ávalos-Britez S, Cabello JV, Arce AL, Watson G, et al. Successful field performance in warm and dry environments of soybean expressing the sunflower transcription factor HB4. Journal of Experimental Botany. 2020;71(10):3142-3156
  169. 169. Hill CB, Li C. Genetic improvement of heat stress tolerance in cereal crops. Agronomy. 17 May 2022;12(5):1-30
  170. 170. Yu Z, Niu L, Cai Q, Wei J, Shang L, Yang X, et al. Improved salt-tolerance of transgenic soybean by stable over-expression of AhBADH gene from Atriplex hortensis. Plant Cell Reports. 2023;42(8):1291-1310
  171. 171. Abdelsattar M, Ramadan AM, Eltayeb AE, Saleh OM, Abdel-Tawab FM, Fahmy EM, et al. Development of transgenic wheat plants withstand salt stress via the MDAR1 gene. GM Crops & Food. 2025;16(1):173-187
  172. 172. Guo M, Wang XS, Guo HD, Bai SY, Khan A, Wang XM, et al. Tomato salt tolerance mechanisms and their potential applications for fighting salinity: A review. Frontiers in Plant Science. 2022;13:949541
  173. 173. Sathee L, Sairam RK, Chinnusamy V, Jha SK, Singh D. Upregulation of genes encoding plastidic isoforms of antioxidant enzymes and osmolyte synthesis impart tissue tolerance to salinity stress in bread wheat. Physiology and Molecular Biology of Plants. 2022;28(9):1639-1655
  174. 174. Kuzma J. Regulating gene-edited crops. Issues in Science and Technology. 2018;35(1):80-85
  175. 175. Voigt B, Münichsdorfer A. Regulation of Genome Editing in Plant Biotechnology: A Comparative Analysis of Regulatory Frameworks of Selected Countries and the EU. Cham: Springer; 2019. pp. 137-238
  176. 176. Sabat M, Tripathy A. Genetically modified and gene-edited food crops: Recent status and future prospects. In: Food Production, Diversity, and Safety under Climate Change. Cham: Springer Nature; 2024. pp. 211-222
  177. 177. Abdul Aziz M, Brini F, Rouached H, Masmoudi K. Genetically engineered crops for sustainably enhanced food production systems. Frontiers in Plant Science. 2022;13:1027828
  178. 178. Serote B, Mokgehle S, Senyolo G, du Plooy C, Hlophe-Ginindza S, Mpandeli S, et al. Exploring the barriers to the adoption of climate-smart irrigation technologies for sustainable crop productivity by smallholder farmers: Evidence from South Africa. Agriculture. 2023;13(2):246
  179. 179. Zhang Y, Ding J, Wang H, Su L, Zhao C. Biochar addition alleviate the negative effects of drought and salinity stress on soybean productivity and water use efficiency. BMC Plant Biology. 2020;20:1-1
  180. 180. Chen J, Wang Y. Understanding the salinity resilience and productivity of halophytes in saline environments. Plant Science. 2024;346:112171

Written By

Ritwik Acharya, Madhushri Das Datta, Debnirmalya Gangopadhyay, Shubhajit Shaw, Rahul Chatterjee and Ankita Manna

Submitted: 08 May 2025 Reviewed: 20 May 2025 Published: 07 July 2025