Association Analysis of Grain Yield and its Components in Spring Wheat (Triticum aestivum L.)

The experiment was designed to investigate the association of some agronomic traits (plant height, number of tillers per plant, flag leaf area, spike length, number of spikelets per spike, number of grains per spike and 1000-grain weight) on grain yield using fifteen wheat genotypes. The obtained results revealed that flag leaf area, spikelets per spike, grains per spike and 1000-grain weight had positive and significant correlation with grain yield at both genotypic and phenotypic levels whereas, spike length was correlated positively and significantly with grain yield at genotypic level but non-significantly at phenotypic level while, tillers per plant showed negative and significant association with grain yield at both levels. Furthermore, path-coefficient analysis revealed that plant height, spike length, grains per spike and 1000-grain weight had positive direct effect on grain yield, whereas, tillers per plant, flag leaf area and spikelets per spike showed negative direct effects on same trait. These results indicated that spike length, grains per spike and 1000-grain weight may be used as direct selection criteria to isolate superior genotypes/lines from genetically mixed populations to develop higher yielding varieties due to positive association and direct effects of these traits on grain yield.