Prospects of Developing Novel Genetic Resources by Chemical and Physical Mutagenesis to Enlarge the Genetic Window in Bread Wheat Varieties

Abstract

Sustainable production and improved genetic gains can be achieved by broadening the genetic window of elite wheat germplasm. Here, we induced mutations in two spring wheat varieties, viz., NN-Gandum-1 (NN-1) and Punjab-11 (Pb-11), by exposing their seeds to ethyl methane sulfonate (EMS) and γ-rays, respectively. We characterized >3500 lines of each NN-1 and Pb-11 derived population in three consecutive generations, viz., M5, M6, and M7, for important traits, e.g., plant height, heading date, spike morphology and rust resistance. We observed significant genetic variation and correlations in both populations for all investigated traits. We observed differences in terms of number of mutants between NN-1 (22.76%) and Pb-11 (26.18%) which could be ascribed to the genotype-by-mutagen interaction. High broad-sense heritability (H2) estimates, that are vital for higher genetic gains, were observed for all of the investigated traits in both populations (H2 = 0.69–0.91 in NN-1 and 0.84–0.98 in Pb-11). Particularly, to breed for rust resistance, we selected a subset (n = 239) of M7 lines that also showed phenotypic variation for other traits. Our studies (1) show the relevance to artificial mutagenesis to create genetic variation in elite germplasm for their immediate use in current breeding programs, and (2) provide material for downstream identification of genes associated with traits of high agronomic importance.

New genetic resources for aphid resistance were identified from a newly developed wheat mutant library

“…Such efforts will pave the way of developing new resilient wheat varieties [ 42 ]. Hence, for enriching the germplasm, it is important to have enough diversity in germplasm which can be utilized for transferring new alleles into the newly developed cultivars [ 43 ].…”

Domestication of newly evolved hexaploid wheat—A journey of wild grass to cultivated wheat

“…Recently, the mutant population was developed by exposing the seeds of a wheat cultivar ‘Punjab-11’ to gamma-rays. The developed mutants were found to be resistant to either leaf rust, yellow rust or, stem rust ( Hussain et al, 2021 ). Few of these mutants also demonstrated high grain quality traits as compared to wild type ( Zulfiqar et al, 2021 ).…”

The diversity of agromorphological characters of Portulaca grandiflora in the MV8 population deriving from recurrent irradiation

“…In addition, an increase in yield component in M6 generation sesame mutants was reported by Monshi and Tabassum (2021). Hussain et al (2021) obtained new wheat genotypes in the M7 population. Many researchers have reported the success of mutation breeding in producing superior varieties.…”