Genetic variation and tolerance indices interactions among wheat (Triticum aestivum L.) accessions under drought stress

Victor Olugbenga Olumekun, Abiola Toyin Ajayi* and Oluwasegun Victor Ibidapo

ABSTRACT    This study was conducted to analyse the level of genetic variability for drought tolerance among wheat (Triticum aestivum L.) accessions adopting the technique of stress tolerance indices of quantitative traits. A factorial experiment (10 x 2) in a completely randomised design replicated three times was adopted utilising pots (300 pots in total) filled with 3.5 kg of unfertilised top soil. Two treatments were applied (after irrigating all pots with 500 ml for two weeks after seed sowing): control (irrigated with 500 ml of water per pot at 2 days interval) and drought stress (irrigated with 500 ml of water at 8 days interval). Targeted data were on plant height and number of tillers per pot, number of spikelets per spike, spike length, seeds per spike, 1000 grain weight and grain yield per pot. Analysis of variance revealed significant variability among accessions for all traits in both conditions. Mean morphological reduction ranged from 14.58% in AKAC10 to 45.08% in AKAC06. Heritability estimate was high for all traits under stress except for number of tillers, spike length and grain weight. High loadings were expressed in PC1 among spike length, spikelets per spike, and seeds per spike and grain yield indices. High loadings in PC2 were displayed by THE number of tillers and spikelets per spike indices. Accessions AKAC09 and AKAC03 with the highest mean indices of 0.79 and 0.75, respectively, were classed as highly tolerant and AKAC10 and AKAC07 with the lowest indices of 0.53 and 0.50, respectively, were classed as the least tolerant accessions. The information provided in the present study would be useful for effective selection of wheat genotypes for drought-prone environments in future breeding programs. © 2020 Department of Agricultural Sciences, AIOU

Keywords: Drought, Heritability, Tolerance, Variability, Wheat

Permanent link to this article: