Root characterization and Identification of drought tolerant dicoccum wheat germplasm lines using Stress tolerance Index (STI)

Abstract

Dicoccum wheat germplasm lines/local collections from different eco-geographical zones were evaluated for their response to terminal drought stress. Assessing the genetic diversity for dicoccum wheat germplasm lines under stress and non-stress conditions was prime objective of the study conducted in Rabi 2020-21. Results of multivariate analysis on root traits revealed that the root length and root volume were highly influencing grain yield under stress conditions. A clustering analysis based on agro-morphological and root traits indicated a good level of genetic diversity among germplasm. Most yield and yield-attributing characteristics showed a significant decrease in mean performance under stress conditions. Drought tolerant germplasm lines were classified based on the Stress Susceptibility Index (SSI) and Stress Tolerance Index (STI). Among the seventy dicoccum germplasm lines DDK-50378 showed good SSI with 0.21. Twenty germplasm lines performed better with STI (>0.9). The germplasm lines DDK-50341, DDK-50380, and DDK-50381 produced better yield with increased root length and root volume under moisture stress than the top yielding standard check DDK 1025. These genotypes proven to be promising and carry genes for drought tolerance and can be further utilized in breeding program for drought tolerance.