Genetic Analysis of Drought Tolerance in Minicore Collection and Segregating Populations of Groundnut Arachis hypogaea L

Abstract

An investigation on genetic analysis of drought tolerance in ICRISAT minicore newlinecollection and recombinants of groundnut was undertaken during summer 2017-18 to newlinesummer 2019-20 at MARS, UAS, Dharwad. Significant genetic variation was observed newlinein minicore collections study as evidenced by wider range and moderate to high PCV newlineand GCV for most of the quantitative, root, oil quality traits studied. High heritability newlineand GAM were recorded for all root traits studied and for most of the quantitative traits newlineand oil quality traits. For drought component traits like RWC, SPAD chlorophyll newlinemeter reading (SCMR), membrane stability index (MSI), stomata frequency (SF), SLA, newlineSLW, photosynthetic rate, stomata conductance and transpiration rate that had low to newlinemoderate PCV, GCV with high heritability with moderate to high GAM. newlineCorrelation analysis during the two seasons indicated that high RWC at pegging newlineand pod development stage, high SCMR, low SLA, increased root length, root volume, newlineMSI at all stages studied, SF 60 DAS, photosynthetic rate at 60 DAS, stomata newlineconductance at 60 DAS, transpiration rate at 60 DAS had contributed for high drought newlinetolerance index for maintenance pod yield under stress condition. Further, the ability of newlinegenotype to maintain physiological traits and yield components could aid groundnut newlinegenotypes in sustaining high pod yield under stress conditions. The reduction in mean newlineperformance of genotypes under moisture stress condition was observed. However, newlinehigher SCMR, RWC, SLA, SF, root length were noted in some of the genotypes viz. newlineICG-3343, ICG-2773, ICG-11855, ICG-3421 and ICG-11219. Superior recombinants newlineidentified for high pod yield with high oleic acid under water stress conditions were viz., newlineDh-256×Dh-245-5-1, Dh-256×ICGV-02266-10-1 and Dh-257×ICGV-02266-35-1. newlineSingle marker analysis in selected lines revealed association of SSR marker TC6E01 newlinewith pod yield under moisture stress conditions and TC5A06 with SCMR under newlinemoisture stress conditions.