Wheat production is increasingly threatened by biotic and abiotic stresses, with stripe rust, caused by Puccinia striiformis f. sp. tritici being among the most devastating diseases. To dissect stripe rust resistance mechanisms, 329 diverse wheat genotypes were evaluated across six distinct environments in India (three locations over two years). The panel exhibited wide variation for stripe rust resistance and was genotyped using a 35K SNP-array. Genome-wide association study (GWAS) revealed 49 significant marker–trait associations (MTAs), explaining 1.58

Global wheat production faces a major challenge in stem rust, caused by Puccinia graminis f. sp. tritici. The rapid evolution of the stem rust pathogen requires continuous global monitoring of its pathotypes. This surveillance is crucial for prioritizing the development of resistant cultivars and implementing other effective control measures. The predominant pathotypes in India since 2014 were selected for investigation, which includes 11 (79G31 = RRTSF), 40 A (62G29 = PTHSC), 40 − 3 (127G29 = PTTSF), and 117-6 (37G19 = KRCSC). To discover MTAs conferring stem rust resistance, an association mapping panel of 1,290 bread wheat accessions was analyzed through 35 K Axiom® Array SNP genotyping and comprehensively phenotyped at seedling stage. A multi-model GWAS approach incorporating BLINK, MLM, CMLM, MLMM, and FarmCPU models identified 14 MTAs associated with resistance across four pathotypes. 11 of the MTAs showed significant genotypic effects across the four pathotypes. Subsequent analysis of the genomic regions flanking these 14 MTAs identified 182 candidate genes with putative roles in plant defense, belonging to multiple distinct protein functional classes. Expression profiling revealed sustained expression of TraesCS6D02G397200, an L-ascorbate peroxidase (APX)-encoding gene on chromosome 6D, across stem rust-infected samples, along with elevated expression of several protein kinase- and F-box protein-encoding genes. The identified genes constitute promising candidates and valuable targets for marker-assisted breeding strategies aimed at enhancing stem rust resistance in wheat. These finding provide a useful foundation for future validation and deployment of resistance associated alleles in wheat development programs.

Iron (Fe) and zinc (Zn) deficiencies frequently limit nutrient acquisition and grain micronutrient accumulation in rice grown under direct-seeded rice (DSR) systems due to reduced micronutrient availability in aerobic soils. Understanding the genetic architecture controlling micronutrient uptake and its association with root system architecture (RSA) is critical for developing nutrient-efficient rice varieties. In this study, a diverse panel of 290 rice genotypes was evaluated for RSA, agronomic traits, and grain Fe and Zn concentration under DSR conditions across three years. Genome-wide association analysis using 18,639 high-quality SNP markers identified 118 significant marker-trait associations distributed across the rice genome. Several loci exhibited pleiotropic effects, linking RSA traits with grain micronutrient accumulation and yield-related traits. Notably, multiple genomic regions co-localized with previously reported QTLs and key genes involved in metal homeostasis, including OsIRO2, OsNAS, OsYSL, OsZIP, OsHMA2, and OsVIT1, suggesting conserved regulatory mechanisms controlling Fe and Zn uptake. Expression profiling under Fe and Zn deficiency further revealed differential regulation of transcription factors and metal transporters between nutrient-efficient and inefficient genotypes, indicating genotype-specific adaptive responses to micronutrient stress. These findings provide insights into the genetic basis of micronutrient uptake and identify promising donors, genomic regions and candidate genes for marker-assisted breeding of nutrient-efficient rice varieties adapted to DSR cultivation systems.

Heat stress is a critical factor affecting global wheat production and productivity. In this study, out of 500 studied germplasm lines, a diverse panel of 126 wheat genotypes grown under twelve distinct environmental conditions was analyzed. Using 35 K single-nucleotide polymorphism (SNP) genotyping assays and trait data on five biochemical parameters, including grain protein content (GPC), grain amylose content (GAC), grain total soluble sugars (TSS), grain iron (Fe), and zinc (Zn) content, six multi-locus GWAS (ML-GWAS) models were employed for association analysis. This revealed 67 stable quantitative trait nucleotides (QTNs) linked to grain quality parameters, explaining phenotypic variations ranging from 3 to 44.5% under heat stress conditions. By considering the results in consensus to at least three GWAS models and three locations, the final QTNs were reduced to 16, with 12 being novel findings. Notably, two novel markers, AX-94461119 (chromosome 2A) and AX-95220192 (chromosome 7D), associated with grain Fe and Zn, respectively, were validated through Kompetitive Allele Specific Polymerase Chain Reaction (KASP) approach. Candidate genes, including the P-loop-containing nucleoside triphosphate hydrolases (NTPases), Bowman-Birk type proteinase inhibitors (BBI), and the NPSN13 protein, were identified within associated genomic regions. These genes could serve as potential targets for enhancing quality traits and heat tolerance in future wheat improvement programs.

Wheat (Triticum aestivum L.), a globally significant cereal crop and staple food, faces major production challenges due to abiotic stresses such as heat stress (HS), which pose a threat to global food security. To address this, a diverse panel of 126 wheat genotypes, primarily landraces, was evaluated across twelve environments in India, comprising of three locations, two years and two growing conditions. The study aimed to identify genetic markers associated with key agronomic traits in bread wheat, including germination percentage (GERM_PCT), ground cover (GC), days to booting (DTB), days to heading (DTHD), days to flowering (DTFL), days to maturity (DTMT), plant height (PH), grain yield (GYLD), thousand grain weight (TGW), and the normalized difference vegetation index (NDVI) under both timely and late-sown conditions using 35 K SNP genotyping assays. Multi-locus GWAS (ML-GWAS) was employed to detect significant marker-trait associations, and the identified markers were further validated using Kompetitive Allele Specific PCR (KASP). Six ML-GWAS models were employed for this purpose, leading to the identification of 42 highly significant and consistent quantitative trait nucleotides (QTNs) under both timely and late sown conditions, controlled by 20 SNPs, explaining 3–58

Wild relatives of wheat possess biological nitrification inhibition (BNI) capacity, which hinders soil nitrification and can be transferred to cultivated bread wheat through methods of wide crossing. The chromosome addition lines (CAL) with Lr#N translocations in chromosome 3BS of wheat were crafted through crosses between Leymus racemosus and Triticum aestivum. Since the CAL has been shown to possess both BNI and other advantageous traits for wheat improvement, it was utilized as a donor to transfer improved BNI capacity into recently released wheat varieties as recipient parents. Marker-assisted backcrossing was deployed. We validated the Sequence Tagged Site markers developed from de-novo sequencing of the Leymus species, along with Kompetitive Allele-specific PCR markers, to identify both translocated and non-translocated lines of wheat and detect the introgressed segments in backcrossed progenies across various cross combinations. For marker validation, Genomic In-situ Hybridization was used to confirm the presence of the translocated region in the recipient lines.

Wheat crops (Triticum aestivum) that are conventionally planted may exhibit susceptibility to yellow rust (YR). However, the disease can be mitigated if the crops are planted earlier than the recommended planting time. A wheat screening experiment was carried out at the Borlaug Institute of South Asia located in Ludhiana, Punjab, India. The purpose of the study was to gain a deeper understanding of the adaptation patterns of early planted wheat. Early planting was found to be more advantageous for production potential, as well as phenology, stature, and physiological traits. In a separate experiment, each year, the same number of genotypes were screened for YR by artificially inoculating them with pathogen spores. The well-adapted genotypes for early establishment tend to possess a greater vulnerability to YR infection. Furthermore, the infection type score for the genotype selected for early planting showed a significantly greater proportion of S (susceptible) type reactions than for the genotypes adapted to early planting. Intriguingly, more R (resistant) and moderately resistant types of reactions were observed in early-adapted genotypes than in timely-adapted ones. Therefore, further concentrated research on YR screening is required to assess the possibility of breeding early sown wheat in the northwest part of the Indo-Gangetic region.

Wheat being one of the most consumed food crops in the world, its production has continuously been increasing across India and globe. Nonetheless, to meet the escalated demand, there was a consensus to develop the stress tolerance varieties. To achieve this, new knowledge and tools that improve the efficiency and speed of wheat improvement can be integrated within the scaffold of most wheat breeding strategies without significant increase in cost. While omics technologies have been continuing to be great intervention, in this chapter, an entire repertoire of various omics tools and technologies are systemically captured.

Context: Water is one of the major limiting factors for wheat production. Mult-environmental evaluation is necessary to identify stable drought tolerant wheat genotypes. Objectives: To identify stable drought tolerant wheat genotypes and reliable phenotypic and/or spectral markers for drought tolerance. Methods: One hundred ninety-six diverse wheat genotypes were evaluated at three different locations in India for two years (E1 to E12). Drought was imposed at the heading stage (Z59) by withholding irrigation until the moisture content reached <45% as compared to the control (100%). Various Morpho-physiological and phenological traits: Days to flowering (DTF) and maturity (DTM), plant height (PH), grain yield (GY), NDVI, canopy temperature depression (CTD), and chlorophyll readings were recorded. Different stress indices and stability models (AMMI - Additive Main Effects and Multiplicative Interaction; WAASB - Weighted Average of Absolute Scores from the singular value decomposition of the matrix of BLUPs; and MTSI - Multi-Trait Stability Index) were used to identify the stable and tolerant genotypes. In addition, discriminate function analysis (DFA) was performed to identify drought tolerant genotypes. Results: Genotype performance reduced significantly under drought for all traits in all environments. Overall, GY was reduced by 35% under drought compared to control. Pooled ANOVA showed that 81% of the variation in grain yield was due to the environment and 10.6% due to its interaction with genotypes. MTSI and WAASBY identified 11 common genotypes with stable performance across all environments. Further, 29 stable genotypes selected by MTSI (with 15% selection intensity) had higher selection differential than other stability models. Further, NDVI at maturity showed a positive and significant correlation [r = 0.41** in E2 and 0.36** in E4) with the GY specifically under drought for two years. Conclusion: MTSI is an effective method for selecting stable wheat genotypes under drought conditions. NDVI may be a high throughput screening tool for drought tolerance. Implications: MTSI may be used to identify stable genotypes, while DFA is useful in selecting drought tolerant genotypes. Further, NDVI can be used in addition to yield traits to screen wheat genotypes for drought tolerance.

Wheat, a major cereal crop, is the most consumed staple food after rice in India. Frequent episodes of heat waves during the past decade have raised concerns about food security under impending global warming and necessitate the development of heat-tolerant wheat cultivars. Wild relatives of crop plants serve as untapped reservoirs of novel genetic variations. In the present study a mapping population comprising 311 BC2F10 backcross introgression lines (BILs) developed by crossing Triticum durum and heat-tolerant diploid wild wheat relative Aegilops speltoides accession pau3809 was used to map QTLs for terminal heat tolerance. The homozygous BILs were evaluated for heat stress tolerance component traits under an optimum environment (OE) and a heat-stressed environment (HE) for the two cropping seasons. Data on spike length, spikelet number per spike, peduncle length, thousand-grain weight, grains per spike, days to heading, days to maturity, grain filling duration, NDVI at heading, plant height and plot yield were recorded. Genotyping-by-sequencing (GBS) of the BILs was carried out, and 2945 high-quality, polymorphic SNPs were obtained. Thirty QTLs were detected for various heat tolerance component traits on chromosomes 1A, IB, 2A, 2B, 3B, 4B, 5A, 5B, 6A and 6B with phenotypic variance ranging from 5 to 11.5%. Several candidate genes reported to play a role in heat stress responses were identified by browsing the 1.85 Mb physical region flanking the stable QTLs detected under the HE. Identified QTL and linked markers can be employed for genomics-assisted breeding for heat tolerance in wheat.

The need to increase the annual genetic gain in crops continues to be urgent to sustain the growing food demand and the sustainability of the agri-food system. An important way to achieve this is by reducing the cycle time of crop breeding. There are various approaches where more than one generation of wheat can be grown each year, including by taking off-season crops. The greenhouse or artificial generation advancement facility is also used for quick generation advancement. However, it is costly and not suitable for developing countries or institutions having financial limitations. Moreover, the amount of breeding material to be handled in speed breeding facilities is also quite limited reducing the chance of obtaining all probable recombinant lines. Therefore, we explored a viable and cost-effective way to grow two wheat crops in a single season under natural field conditions in a location in the state of Madhya Pradesh, India where wheat has never been grown in the off-season. The experiment was conducted using six genotypes, varying in days to maturity on four different treatment combinations at the research farm of Borlaug Institute for South Asia (BISA), Jabalpur, Madhya Pradesh which falls under the Central Zone (CZ) of India. Out of four treatments, we got seed germination in two treatments with a success rate of >80%. The results proved that it is possible to obtain at least two generations of wheat crop under field conditions in the location used. This approach not only saves resources and time but also provides an opportunity to make selections in breeding populations at least from the first cycle. The results serve as a base to further refine this technique and eventually use it for wheat breeding or off-season multiplication of seeds to fast-track the entire process of varietal development and its dissemination.

Bread wheat (T. aestivum) is one of the world's most widely consumed cereals. Since micronutrient deficiencies are becoming more common among people who primarily depend upon cereal-based diets, a need for better-quality wheat varieties has been felt. An association panel of 154 T. aestivum lines was evaluated for the following quality traits: grain appearance (GA) score, grain hardness (GH), phenol reaction (PR) score, protein percent, sodium dodecyl sulfate (SDS) sedimentation value, and test weight (TWt). In addition, the panel was also phenotyped for grain yield and related traits such as days to heading, days to maturity, plant height, and thousand kernel weight for the year 2017-18 at the Borlaug Institute for South Asia (BISA) Ludhiana and Jabalpur sites. We performed a genome-wide association analysis on this panel using 18,351 genotyping-by-sequencing (GBS) markers to find marker-trait associations for quality and grain yield-related traits. We detected 55 single nucleotide polymorphism (SNP) marker trait associations (MTAs) for quality-related traits on chromosomes 7B (10), 1A (9), 2A (8), 3B (6), 2B (5), 7A (4), and 1B (3), with 3A, 4A, and 6D, having two and the rest, 4B, 5A, 5B, and 1D, having one each. Additionally, 20 SNP MTAs were detected for yield-related traits based on a field experiment conducted in Ludhiana on 7D (4) and 4D (3) chromosomes, while 44 SNP MTAs were reported for Jabalpur on chromosomes 2D (6), 7A (5), 2A (4), and 4A (4). Utilizing these loci in marker-assisted selection will benefit from further validation studies for these loci to improve hexaploid wheat for better yield and grain quality.

Heat stress is a critical factor affecting global wheat production and productivity. In this study, out of 500 studied accessions a diverse panel of 126 wheat genotypes grown under twelve distinct environmental conditions was analyzed. Using 35K single-nucleotide polymorphism (SNP) genotyping assays and trait data on five biochemical parameters, including grain protein content (GPC), grain amylose content (GAC), grain total soluble sugars (TSS), grain iron (Fe), and zinc (Zn) content, six multi-locus GWAS models were employed for association analysis. This revealed 67 significantly associated QTNs linked to grain quality parameters, explaining phenotypic variations ranging from 3–44% under heat stress conditions. By considering the results in consensus to at least three GWAS models and three locations, the final QTNs were reduced to 17, with 14 being novel findings. Notably, two novel markers, AX-94461119 (chromosome 6A) and AX-95220192 (chromosome 7D), associated with grain iron and zinc, respectively, were validated through KASP approach. Candidate genes, such as chaperonin Cpn60/GroEL/TCP-1 family, P-loop containing nucleoside triphosphate hydrolases (NTPases), Bowman-Birk type proteinase inhibitor (BBI), and NPSN13 protein, were identified from the associated genomic regions, which could be potentially targeted for improving quality traits and heat tolerance in wheat.

The journal consistently attracts the most important and highly innovative papers from the current research; our commitment to rapid publication ensures that these are published in the fastest time possible. In addition to primary papers from world-renowned experts, the Journal contains authoritative reviews that summarize and evaluate the most significant recent developments. Also included are special reports, original short papers containing innovative and time-sensitive information. Submitted articles undergo a preliminary review by the editor. Some articles may be returned to authors without further consideration. Those being considered for publication will undergo further assessment and peer-review by the editors and those invited to do so from a reviewer pool. ​ Official Journal of the: International Society of Hypertension European Society of Hypertension

Terminal heat stress and foliar diseases like rusts and spot blotch are the major concerns for sustainable wheat production in South Asia. Eastern Indo-Gangetic plains witness the crucial role of heat stress during grain-filling duration (GFD) and occurrence of rust diseases and spot blotch in wheat. One hundred promising wheat genotypes were selected from five international wheat yield trials and evaluated at three sites in India for yield components and disease resistance. To identify potential donors, these lines were further screened under timely sown (normal sown) and late sown (heat stress) conditions. Analysis of variation in the studied traits revealed significant differences among all the genotypes in both environments. Grain yield showed a positive and significant correlation with NDVI, chlorophyll index, flag leaf length, flag leaf area, tiller per plant, number of grains per spike, peduncle length and 1000 grain weight (TGW) in both environments. Grain zinc and iron content was substantially increased under late sown condition. As per heat susceptibility index of GFD, TGW, NDVI and grain yield per plot, 10 tested entries were found heat tolerant. Ten promising entries with low disease score were listed as spot blotch donors. Markers linked with seven rust resistance genes, three spot blotch genes and two markers linked with quality-related traits, namely yellow pigment (Psy-A1) and polyphenol oxidase activity (Ppo-1A) and rust pathotypes, were also used to identify the presence of individual genes. Promising entries 46 (CWYT-613; GID 7631433) and 58 (41ESWYT-137; GID 8240588), common for both tested conditions, were identified and promoted under the breeding programme.

Targeted genome editing is a fast-paced technology for inducing mutations in the genes of interest, especially in the complex genome of bread wheat. The foremost requirement to understand gene function is to either modify/edit it or knock out the gene completely. The major bottleneck to understand gene function in wheat is the existence of homologous loci at three sub-genomes which are difficult to edit simultaneously. CRISPR/Cas9-based genome editing opened up new prospects to tailor crop traits and to generate desirable variability, which could be exploited in crop improvement. Targeted genome editing has been advanced in preciseness, minimizing off-targets, transgene-free, multiplexing, higher editing efficiency, and better transformation protocols since its first application in wheat. Significant developments in the field of precision editing and brief mention of altered traits and achievements are discussed.

Crop failure is largely caused by various climate hazards, and among them, heat stress is the primary factor hindering crop production. The significant global loss of crop yield is primarily due to heat-related damage during the reproductive phase. Terminal heat stress has been well documented in wheat, causing morphophysiological alterations, biochemical disruptions, and reduction of genetic potential. The formation of shoots and roots, the effect on the double ridge stage, and early biomass in the vegetative stage are also impacted by heat stress. The final negative outcomes of heat stress include reduced grain number and weight, slower grain filling rate, reduced grain quality, and shorter grain filling duration. Plants have developed mechanisms to adapt to heat stress through modifications in their morphological or growth responses, physiological and biochemical pathways, and changes in enzyme reactions. Numerous heat tolerance genes have been identified in wheat, but the more extensive study is needed to increase heat tolerance in crops to satisfy the food demands of the world’s growing population. The global food policy needs to prioritize and promote additional joint research and the development of heat-tolerant wheat breeding to ensure the world’s food security.

Wheat, an important cereal crop globally, faces major challenges due to increasing global population and changing climates. The production and productivity are challenged by several biotic and abiotic stresses. There is also a pressing demand to enhance grain yield and quality/nutrition to ensure global food and nutritional security. To address these multifaceted concerns, researchers have conducted numerous meta-QTL (MQTL) studies in wheat, resulting in the identification of candidate genes that govern these complex quantitative traits. MQTL analysis has successfully unraveled the complex genetic architecture of polygenic quantitative traits in wheat. Candidate genes associated with stress adaptation have been pinpointed for abiotic and biotic traits, facilitating targeted breeding efforts to enhance stress tolerance. Furthermore, high-confidence candidate genes (CGs) and flanking markers to MQTLs will help in marker-assisted breeding programs aimed at enhancing stress tolerance, yield, quality and nutrition. Functional analysis of these CGs can enhance our understanding of intricate trait-related genetics. The discovery of orthologous MQTLs shared between wheat and other crops sheds light on common evolutionary pathways governing these traits. Breeders can leverage the most promising MQTLs and CGs associated with multiple traits to develop superior next-generation wheat cultivars with improved trait performance. This review provides a comprehensive overview of MQTL analysis in wheat, highlighting progress, challenges, validation methods and future opportunities in wheat genetics and breeding, contributing to global food security and sustainable agriculture.