Genetic variability for different biometric traits in wheat (Triticum aestivum L.) under medium fertility conditions

This study was carried out at CCS HAU, Regional Research Station, Bawal (Haryana) during rabi 2012-13 with 24 wheat genotypes to assess the genetic variability, correlation and path coefficient analysis under medium fertility conditions. Ten biometric traits viz., plant height (cm), spike length (cm), number of tillers per meter row, number of grains per spike, days to heading, days to maturity, 1000-grain weight (g), harvest index (%), biological yield (kg/plot) and grain yield (kg/plot). The higher phenotypic (PCV) and genotypic coefficients of variation (GCV) were exhibited by number of grains per spike, number of tillers per meter row, harvest index, biological yield, 1000-grain weight and grain yield. Moderate to high heritability coupled with high genetic advance as per cent of mean was observed for number of grains per spike, 1000-grain weight, grain yield, biological yield, number of tilers per meter row, harvest index and plant height, indicating the importance of these traits in selection and crop improvement. The genotypic correlation estimates showed significant positive association of grain yield with harvest index, 1000-grain weight, days to heading and maturity. Path coefficient analysis at genotypic level revealed high positive direct effect of harvest index and biological yield and negative direct effect by number of tillers per meter row on grain yield. Hence these are the main contributors to grain yield under medium fertility conditions.