Analyzing Sunn pest resistance in bread wheat genotypes using phenotypic characteristics and molecular markers.

Abstract

Sunn pest is one of the most destructive insects in the western and central parts of Asia causing severe reductions of wheat yield and flour quality. Therefore, an effort was undertaken to find effective resistance by analyzing genetic variation among 25 wheat genotypes artificially infested in field-cages as well as using start codon targeted (SCoT) polymorphism and inter- retrotransposon amplified polymorphism (IRAP) markers. High variation was revealed amongst genotypes with Sunn pest resistance characteristics including Bayat, Bezostaya, Sayson, Line93, Line120, Rashagol, Golsepi and AarasGolsoor, which were classified as resistant to moderately resistant. SCoTs and IRAPs were determined as efficient markers for studying genetic diversity. The non-parametric Kruskal-Wallis test was conducted to evaluate the effect of specific SCoT and IRAP amplicons on Sunn pest resistance characteristics for wheat genotypes. The stepwise regression analysis exhibited seven informative SCoTs and IRAPs explaining the highest resistance characteristics variation ranging from 25.7-50.1 to 17.6-40.1, respectively. The relationship between resistance of genotypes and informative SCoT and IRAP amplicons was found based on canonical discriminant analysis showing the capacity of informative markers for functional marker selection method and screening the wheat germplasms for Sunn pest resistance characteristics.