Indian Wheat Genomics Initiative for Harnessing the Potential of Wheat Germplasm Resources for Breeding Disease-Resistant, Nutrient-Dense, and Climate-Resilient Cultivars

Abstract

Wheat is one of the major staple cereal food crops in India. However, most of the wheat-growing areas experience several biotic and abiotic stresses, resulting in poor quality grains and reduced yield. To ensure food security for the growing population in India, there is a compelling need to explore the untapped genetic diversity available in gene banks for the development of stress-resistant/tolerant cultivars. The improvement of any crop lies in exploring and harnessing the genetic diversity available in its genetic resources in the form of cultivated varieties, landraces, wild relatives, and related genera. A huge collection of wheat genetic resources is conserved in various gene banks across the globe. Molecular and phenotypic characterization followed by documentation of conserved genetic resources is a prerequisite for germplasm utilization in crop improvement. The National Genebank of India has an extensive and diverse collection of wheat germplasm, comprising Indian wheat landraces, primitive cultivars, breeding lines, and collection from other countries. The conserved germplasm can contribute immensely to the development of wheat cultivars with high levels of biotic and abiotic stress tolerance. Breeding wheat varieties that can give high yields under different stress environments has not made much headway due to high genotypes and environmental interaction, non-availability of truly resistant/tolerant germplasm, and non-availability of reliable markers linked with the QTL having a significant impact on resistance/tolerance. The development of new breeding technologies like genomic selection (GS), which takes into account the G × E interaction, will facilitate crop improvement through enhanced climate resilience, by combining biotic and abiotic stress resistance/tolerance and maximizing yield potential. In this review article, we have summarized different constraints being faced by Indian wheat-breeding programs, challenges in addressing biotic and abiotic stresses, and improving quality and nutrition. Efforts have been made to highlight the wealth of Indian wheat genetic resources available in our National Genebank and their evaluation for the identification of trait-specific germplasm. Promising genotypes to develop varieties of important targeted traits and the development of different genomics resources have also been highlighted.

Wheat quality: A review on chemical composition, nutritional attributes, grain anatomy, types, classification, and function of seed storage proteins in bread making quality

“…Today, it is usually thought that quality differences are strongly influenced by alterations in the quality of glutenin (85). An increase in the world's population of almost 10 billion is expected by 2050, which will result in an increase in wheat demand at a rate of approximately 1.7 annually (94). Therefore, creating a sufficient supply response will persist as a policy challenge throughout the 21st century.…”

“…Wheat breeders' responsibility and their role in developing better varieties of wheat are becoming more significant in the improvement of crop production (95). Wheat productivity is vulnerable to newly developed diseases and pests, inadequate water resources, limited arable land, and quickly altering climatic situations (94,96).…”

“…Tilletia indica (Karnal bunt) disease is not only responsible for yield loss but also affects the quality of grain due to the infection of kernels. This disease was detected in various other countries, such as Mexico, Pakistan, India, Iran, Nepal, Afghanistan, Iraq, South Africa, and the United States (94).…”

“…In contrast to biotic stress resistance, the resistance gene plays a small role in defending wheat against insects due to the substantial effect of temperature and light on the existence and performance of the insects (94). Continuous damage to crop production caused by pests and diseases is one of the key limitations in wheat breeding and, therefore, food sufficiency globally.…”

“…The induction of chromosome restitution in meiosis at the time of male gamete development is a major problem caused by climate variation. Heat stress at the terminal stage of the wheat crop halts plant growth and the accumulation of starch, causing yield fickleness (94). On the other hand, global warming brutally disturbs weather patterns, ensuing temperature extremes, frequent frost, drought, and snowfall (94).…”