Investigating the impact of high temperature on growth and yield of Lablab purpureus L. inbred lines using integrated phenotypical, physiological, biochemical and molecular approaches.

Abstract

A continuous increase in global mean temperature has become a major challenge for present and future agricultural productivity at worldwide. Therefore, present study was conducted to assess the impact of high temperature (HT) stress on seven Lablab purpureus L. inbred lines along with two parents viz, Arka Vijay and Kashi Khushal as check, to evaluate any genotypic variations exist among inbred lines for HT stress tolerance. The results show that HT induced higher levels of foliar injury in all inbred lines that significantly increased membrane damage, declined photosynthetic pigment contents and redox metabolites which ultimately led to the reduction in their growth and yield. However, among all the inbred lines used, three inbred lines viz, VRBSEM-1, VRBSEM-3 and VRBSEM-15 showed comparatively enhanced enzymatic and non-enzymatic antioxidants with increased secondary metabolites content as well as improved growth and yield related traits, thereby confirming that these inbred lines were efficiently utilizing reactive oxygen species as signaling molecule which regulated their growth and developmental process under HT stress. DNA fingerprinting analysis through ISSR and RAPD markers also established the genetic relationships among the inbred lines that coincides with above physiological and biochemical characterization, and grouped VRBSEM-1 & VRBSEM-3 and VRBSEM-9 & VRBSEM-15 inbred lines into one group and VRBSEM-8, VRBSEM-10, VRBSEM-14 into another group. The experimental findings clearly depict that all the cultivars of L. purpureus L. showed differential response to HT stress. Inbred lines with enhanced biochemical and physiological traits can be crossed to high yielding agronomical elite materials which can help plant breeders in selecting resistant cultivars for the area experiencing high temperature during the cropping season.