Correlation and Path Coefficient Analysis for Yield and Yield Components of Soybean Genotypes Under Different Planting Density

Abstract

Two field experiments were conducted during 2010 and 2011 seasons in at the Research and Experimental Center of the Faculty of Agriculture at Moshtohor, Benha University, Egypt, to evaluate 5 soybean genotypes i.e., Clark, Crawford, Giza22, Giza35 and Giza83 under three planting densities i.e., 70000, 140000 and 210000 plants fed-1 and estimate the relationships between seed yield and its components. The results could be summarized from the combined analysis of the two seasons which indicated that Giza83 genotype significantly exceeded other genotypes in plant height, number of pods plant-1, weight of pods plant-1, weight of seeds plant-1, 100-seed weight, straw yield fed-1 and seed yield fed-1. Also, the genotypes Giza83 and Giza22 genotypes were superior in number of branches plant-1 and number of seeds pod-1 over others soybean genotypes. Decreasing planting density to 70000 plants fed-1 was increased significantly number of branches plant-1, number of pods plant-1, number of seeds pod-1, weight of pods plant-1, weight of seeds plant-1, shelling percentage and 100-seed weight. However, increasing plant density form 70000 up to 210000 plants fed-1 increased significantly plant height, biological, straw and seed yields fed-1. A significant interaction effect between soybean genotypes and planting density was detected for plant height, number of branches plant-1, number of pods plant-1, 100 seed weight and seed yield fed-1. The highest number of branches plant-1, number of pods plant-1, 100-seed weight were obtained from Giza83 at 70000 plants fed-1, while plant height and seed yield fed-1 were obtained from Giza83 at 210000 plants fed-1. Significant positive phenotypic correlation values were detected between seed yield plant-1 and each of branches plant-1, number of pods plant-1, number of seeds pod-1 and 100-seed weight. According to path analysis, No. of pods plant-1 through 100-seed weight proved to have the highest indirect effect to seed yield plant-1 (26.47%) followed by direct effect 100-seed weight (15.51%) and direct effect No. of pods plant-1 (14.04%).