Variability and interrelationship analysis in bread wheat under moisture stress conditions

Abstract

A study was undertaken to estimate the genetic variability, correlation and path coefficient analysis of yield andyield contributing traits in 90 wheat cultivars grown under moisture stress. The analysis of variance revealedhighly significant differences among varieties for all the traits. The GCV and PCV were high for effectivetillers, grain filling duration, grain weight per spike, grains per spike, grain yield, spike length, plant height anddays to heading. The genotypic coefficients of the variation for most of the characters were almost equal to itsphenotypic coefficient of variation, thereby suggesting predominance of genetic components that was furthersupported by high heritability estimates for days to heading, days to anthesis, days to physiological maturity,grain filling duration, plant height, spike length and effective tillers. High heritability coupled with high geneticadvance was registered for days to heading, grain filling duration, plant height, spike length, effective tillersand grain yield indicated predominance of additive gene action. The significant correlation of harvest indexand biological yield with grain yield were recorded, whereas, days to heading had positive and significantcorrelation with days to anthesis. It is also important to mention that under moisture stress conditions, CT – atgrain filling stage had positive and significant association with CT – at anthesis stage but negative and significantassociation with grain yield. Path analysis revealed that days to physiological maturity, grain weight per spike,harvest index and biological yield had positive direct effects on grain yield; however, days to anthesis and grainfilling duration had negative direct effects. It may be concluded that for breeding of water use efficient wheatgenotypes, traits like harvest index, biological yield, grain filling duration, grains number and weight per spikeneed due consideration for yield improvement in wheat.