Title: Impact of abiotic stress on performance of Nepalese Wheat (Triticum aestivum L.) genotypes and molecular characterization by using stress linked SSR marker
Abstract:
Abiotic stresses are the major yield limiting factors for wheat production worldwide. Identification of stable and high yielding genotypes of wheat could be done using additive main effects multiplicative interaction (AMMI) and genotype×genotype×environment biplot (GGE). Twenty elite wheat genotypes including two commercial checks Bhirkuti and Gautam were evaluated in an alpha lattice design of experiment at Institute of Agriculture and Animal Sciences (IAAS), Paklihawa Campus and Sunwal,Nawalparasi in growing season of 2022-2023 under Irrigated, Heat stress, and drought environments. The combined Analysis of variance revealed environment had a significant effect on all the quantitative traits of wheat. DTB, DTH, DTA, Ph, SL, NSPMS,NSPS and NGPS were reduced by 11.85%, 14.50%, 15.32%, 7.53%, 4.02%, 12.03%, 5.43%, 9.46% under Heat stress environment was and by 12.28%,15.25%,16.24%, 16.33%, 16.17%,8.65%, 16.71%, 23.75% under drought environment as compared to Irrigated environment. Similarly, Grain yield was reduced by 24.37% under heat stress whereas 48.72% under heat drought environments as compared to irrigated environment. Which-Won-Where model showed, BL 4919, NL 1368, and NL 1387 had a best performance under Irrigated, heat stress and drought environments of Rupandehi whereas, NL 1384 was best under irrigated and NL 1179 performed best under both heat stress and heat drought environments of Nawalparasi. Assessing molecular study on twenty genotypes by using 16 SSR stress linked marker showed considerable variability and classified into four clusters whereas Bhrikuti showed distict classes probably due to different in their parentage. Genetic variability among existing germplasm plays important role for enhancing amelioration of genotypes and it can also be used in further hybridization programme.
Keywords: Wheat, Adaptability, Stability, Genetic diversity