Assessment of genetic diversity and agronomic traits of durum wheat germplasm under drought environment of the northern Great Plains

Abstract

Durum wheat (Triticum turgidum L. ssp. durum) is an important food crop worldwide. Modern breeding has yielded elite durum wheat cultivars with improved grain yield, end‐use quality, and disease resistance. In this study, we compared 150 breeding lines from the North Dakota State University (NDSU) durum wheat breeding program to 163 durum landraces using a large set of single nucleotide polymorphism (SNP) markers. We found that the genetic diversity of the NDSU durum breeding population was decreased by ∼60% relative to collection of 163 landraces. Selective sweep analysis identified several candidate regions that might have undergone breeding selection. Also in this study, over 260 worldwide durum wheat accessions were evaluated in drought environments of the northern Great Plains for 3 yr, a major growing area of durum wheat in the United States. One line showed significantly higher grain yield than the local elite cultivars. A number of lines showed significantly higher grain yield component traits like seeds per spike and thousand‐kernel weight. Those desirable lines may contain complementary favorable alleles and can possibly be used to improve grain yield under drought stress. Genome‐wide association mapping found no major quantitative trait loci (QTL) but a number of QTL with minor effect for grain yield, which could be explained by grain yield's complex genetic nature, the rare frequency of the novel complementary alleles, and the limited number of environments and replications for phenotypic evaluation in the study. Further QTL mapping using biparental populations derived from the identified desirable lines and elite cultivars may be able to identify the QTL related to grain yield, which can facilitate introgression of the complementary favorable alleles through marker‐assisted selection.

Identification Method of Wheat Cultivars by Using a Convolutional Neural Network Combined with Images of Multiple Growth Periods of Wheat

“…To meet the food needs of all parts of the world, people have cultivated about 30,000 wheat varieties, but mainly hexaploid bread wheat (Triticum aestivum), which accounts for about 95% of the world's wheat production [3]. The implementation of modern wheat breeding programs has accelerated the selection and breeding of new wheat varieties [4]. While they have improved the efficiency of the wheat industry, these programs have also resulted in the frequent mixing of wheat varieties.…”

Molecular Genetic Diversity of Local and Exotic Durum Wheat Genotypes and Their Combining Ability for Agronomic Traits under Water Deficit and Well-Watered Conditions

“…The significant difference detected among the evaluated genotypes indicates sufficient variability and promising resources that could be utilized for breeding drought-tolerant genotypes. In this context, Nouri et al [39]; Mohammadi [40]; Salsman et al [41]; and Mohammadi et al [42] reported high genetic diversity for agronomic traits in durum wheat under drought stress conditions.…”

Plant Breeding and Management Strategies to Minimize the Impact of Water Scarcity and Biotic Stress in Cereal Crops under Mediterranean Conditions

“…Landraces are usually adapted to harsh environments, namely drought and heat conditions; thus, they are suited to low input agriculture. Comparisons between landraces and modern varieties indicate that, in most cases, yields of the current varieties are higher than that of landraces, because most comparisons are made in favorable environments and under intensive agricultural practices [103,104]. The idea is not to substitute the best-adapted local varieties for landraces but to use the best landraces as a source of desirable genes for better adaptation to abiotic stress.…”

“…However, to make this breeding process a success, a large germplasm collection is required in order to locate suitable genes for drought tolerance for a particular target environment [100]. In some cases, such as yield under drought conditions, the interesting traits are not regulated by major genes but, rather, several QLTs with minor effects [104]. In those cases, finding genetic markers suitable for marker-assisted selection may present some practical challenges.…”