NOVEL GENETIC DIVERSITY OF THE ALIEN D-GENOME SYNTHETIC HEXAPLOID WHEAT (2n=6x=42, AABBDD) GERMPLASM FOR VARIOUS PHENOLOGY TRAITS

The current study evaluates genetic penetrance and expressivity of an alien genome introgression in a set of 117 primary synthetic hexaploid wheat (SHW) accessions. These SHW's have originated from durum wheat /accessions with three sets of durum wheat cultivars ALTAR 84, D67.2 and CERCETA as the female and diverse Ae. tauschii accessions as the pollen parents. Diversity of the 12 important traits (Growth habit, pigmentation, chlorophyll content, leaf area index, crop digital ground cover, awn size, awn length, and several seed digital imaging parameters)revealed significant variation for the respective traits, leading to the conclusion that Ae. tauschii accessions have tremendous diversity than the durum controls. Further, the value deviations within each attribute had a range of being lower or higher than their durum wheat female parents and these observations allowed us to use the variations as selective sieves and narrow down the desirable SHW's that would be advantageous to exploit for wheat breeding and cultivar improvement programs. Selections were made and a group of 41SHWaccessions were identified that will after an intermediate DNA diversity evaluation form a crisper final set for user friendly utilization. The range of selections shows multiple trait advantages for exploitation in both irrigated and rain-fed conditions. This pivotal study sets the foundation to better define the D genome SHW's for efficient utilization in future research investigations. Our results have implications in widening the genetic base of hexaploid bread wheat and may facilitate the development of agronomically desirable wheat cultivars