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Heat and drought are two important constraints to global wheat productivity; understanding the genotypic responses for quality parameters under harsh production conditions (drought and heat) is very important for developing nutrient‐dense wheat varieties. A set of 15 modern bread wheat (Triticum aestivum L. subsp. aestivum) and durum wheat (Triticum turgidum subsp. durum) cultivars were tested in nine environments, including three different production conditions (normal, heat and drought) during 2020–21. Genotype stability performance for yield, nutrition and quality parameters is assessed using multienvironment trials through AMMI and GGE Biplot analysis. We discovered intriguing stress dynamics in grain zinc content (Zn) and grain iron content (Fe). Under heat stress, zinc concentration increases but decreases under drought stress, while iron does the opposite. Selecting zinc, starch and kernel weight under terminal heat stress can boost yield. Protein content and yield are inversely related, making it difficult for breeders to optimise both traits. G × E interactions and stability indices across all environments have found genotypes with high‐yielding stable genotypes, G12 (MP1358) (42.09 ppm) and G5 (HI1544) (42.41 ppm) have high Fe content. G12 (MP1358) (14.98%) ranked highest in protein concentration. Meanwhile, for Zn content, G11 (MACS 4058) (45.23 ppm) and G15 (WH730) (42.44 ppm) were top performers across environments. G7 (HI 1636) and G12 (MP1358) stand out as a win‐win genotype for their high potential and stability in yield, protein, Zn and Fe content. Our study shows the complex relationships and possible suggestions for targeted breeding programmes under heat and drought stress conditions to improve wheat grain quality and micronutrient profiles without yield loss. [ABSTRACT FROM AUTHOR]

Wheat is a major staple food crop for food security in India and South Asia. The current rate (0.8–1.2%) of genetic gain in wheat is significantly shorter than the 2.4% needed to meet future demand. The changing climate and increased yield loss due to factors such as terminal heat stress necessitate the need for climate-resilient practices to sustain wheat production. At ICAR-Indian Institute of Wheat and Barley Research in Karnal, Haryana, India, a new High Yield Potential Trial (HYPT) was conceptualized and subsequently conducted at six locations in the highly productive North Western Plain Zone (NWPZ). An attempt was made to harness higher wheat yields through the best pipeline genotypes suitable for early sowing and modified agronomic practices to explore the feasibility of a new approach that is profitable to farmers. The modified agronomic practices included like early sowing, application of 150% recommended dose of fertilizers, and two sprays of growth regulators (Chlormaquate chloride and Tebuconazole) to prevent lodging. The mean yield in the HYPT was 19.4% superior compared to the best trials conducted during the normal sowing time. A highly positive and significant correlation of grain yield with grain filling duration (0.51), biomass (0.73), harvest index (0.75), normalized difference vegetation Index (0.27), chlorophyll content index (0.32), and 1000-grain weight (0.62) was observed. An increased return of USD 201.95/ha was realized in the HYPT when compared to normal sowing conditions. This study proves that new integrated practices have the potential to provide the best profitable yields in wheat in the context of climate change. [ABSTRACT FROM AUTHOR]

Genomic regions governing grain protein content (GPC), 1000 kernel weight (TKW), and normalized difference vegetation index (NDVI) were studied in a set of 280 bread wheat genotypes. The genome-wide association (GWAS) panel was genotyped using a 35K Axiom array and phenotyped in three environments. A total of 26 marker-trait associations (MTAs) were detected on 18 chromosomes covering the A, B, and D subgenomes of bread wheat. The GPC showed the maximum MTAs (16), followed by NDVI (6), and TKW (4). A maximum of 10 MTAs was located on the B subgenome, whereas, 8 MTAs each were mapped on the A and D subgenomes. In silico analysis suggest that the SNPs were located on important putative candidate genes such as NAC domain superfamily, zinc finger RING-H2-type, aspartic peptidase domain, folylpolyglutamate synthase, serine/threonine-protein kinase LRK10, pentatricopeptide repeat, protein kinase-like domain superfamily, cytochrome P450, and expansin. These candidate genes were found to have different roles including regulation of stress tolerance, nutrient remobilization, protein accumulation, nitrogen utilization, photosynthesis, grain filling, mitochondrial function, and kernel development. The effects of newly identified MTAs will be validated in different genetic backgrounds for further utilization in marker-aided breeding. [ABSTRACT FROM AUTHOR]

Drought is one of the major abiotic constraints on wheat yields and also for sustainability of production levels around the world. In the near future, the occurrence likelihood of droughts is predicted to become more common, due to changing climatic conditions, thereby posing a serious threat to the food security system. Heterogeneity, in its time of occurrence and severity levels, is likely to further augment the complexity of drought conditions. Although wheat crop growth has progressively risen to good levels, as evident by notable increases in both area and production, the expected wheat demand for the ever-growing population is quite high. Besides crop yield volatility in the era of climate change and dwindling resources, "trait-based" breeding programs are required, so as to develop high yielding, climate resilient and stable genotypes, at a faster pace. For this to happen, a broad genetic base and wider adaptability to suit varied agro-ecologies would provide enough scope for their quicker spread. The current review places emphasis on making distinct categories of the wheat cultivars/advanced breeding lines, as tolerant, moderately tolerant or susceptible to drought stresses, duly supported by an extensive up-to-date literature base and will be useful for wheat researchers, in order to choose the best potential donors as parents, coupled with the associated traits for the development of drought-tolerant wheat varieties, and also to facilitate molecular studies. [ABSTRACT FROM AUTHOR]

Various attempts have been made to understand the traits and genes associated with heat stress tolerance in wheat (Triticum aestivum L.) in the field and under controlled conditions. Attempts made under controlled conditions have not been conclusive, mainly through a lack of sufficient precision in simulating the ambient temperature dynamics and microenvironments prevalent in the field. In addition, inconsistency in field phenotyping is a major concern. Hence, we attempted to develop a method for phenotyping wheat for heat stress tolerance through a novel temperature‐controlled phenotyping facility (TCPF), along with an inexpensive tool to ensure uniform crop establishment. The objective was to improve the precision of assessing plants' responses to elevated temperatures, particularly when these experiments are challenged by a large number of genotypes to be screened that show significant variations in their phenology. The study involved 75 genotypes from a recombinant inbred line population with differing responses to heat stress under three conditions: in the TCPF and in the field [regular field season and late sown (LS)] across two consecutive years. The results revealed that the yield components were different under LS and TCPF conditions. These differences reflected the plants' responses to morphophenological adaptations arising from the late planting time and were not really reflective of the heat stress response. However, greater precision in differentiating high‐temperature responses in the TCPF was evident from the repeatability in terms of growth, physiology, and productivity. This could be attributed to uniform crop establishment and improved capacity to maintain the desired temperature for phenotyping. [ABSTRACT FROM AUTHOR]

Terminal heat stress has the potential negative impact on wheat production across the world, especially in South Asia. Under the threat of terminal heat stress, wheat genotypes with stay green trait would suffer from high temperature stress during their long grain filling duration ( GFD). The genotypes with short GFD would be advantageous. To identify quantitative trait loci (QTL) for heat tolerance, a RIL population of K 7903 (heat tolerant) and RAJ 4014 (heat sensitive) wheat genotypes was investigated under timely and late-sown conditions. Heat susceptibility index of GFD, yield components and traits under late-sown condition were used as phenotypic data for QTL identification. Stable QTLs associated with these traits were identified on chromosomes 1B, 2B, 3B, 5A and 6B. The LOD value ranged from 2.9 to 5.0 and the corresponding phenotyping variation explained ranged from 12.0-22%. QTL for heat susceptibility index for the grain filling duration were colocalized with QTL for productive tillers under late sown and GFD under late-sown condition on chromosomes 1B and 5A, respectively. These genomic regions could be exploited for molecular wheat breeding programmes targeting heat tolerance. [ABSTRACT FROM AUTHOR]

An increase in the rate of crop improvement is essential for achieving sustained food production and other needs of ever-increasing population. Genomic selection (GS) is a potential breeding tool that has been successfully employed in animal breeding and is being incorporated into plant breeding. GS promises accelerated breeding cycles through a rapid selection of superior genotypes. Numerous empirical and simulation studies on GS and realized impacts on improvement in the crop yields are recently being reported. For a holistic understanding of the technology, we briefly discuss the concept of genetic gain, GS methodology, its current status, advantages of GS over other breeding methods, prediction models, and the factors controlling prediction accuracy in GS. Also, integration of speed breeding and other novel technologies viz. high throughput genotyping and phenotyping technologies for enhancing the efficiency and pace of GS, followed by its prospective applications in varietal development programs is reviewed. • Genomic selection (GS) promises faster breeding through increased selection accuracy. • Design of TP and GS models play critical role in prediction accuracy. • Speed breeding and high throughput genotyping and phenotyping can enhance GS efficiency. [ABSTRACT FROM AUTHOR]

DBW222 is characterized by potential yield of 8210 kg ha-1 under high fertility when sown in timely conditions in North India. It possesses better agronomic attributes and has better adaption to sowing time, high rust resistance, quality attributes, and lodging tolerance because of a shorter 2nd internode and wider diameter. [ABSTRACT FROM AUTHOR]