Variability and interrelationships of grain quantity and quality characteristics in soybean

The objective of this study was to estimate the efficiency and reliability of grain quantity and quality characteristics in soybean (Glycine max (L.) Merrill) as selection criteria in breeding for higher grain yield. Trials were conducted on the experimental field of the Agricultural Institute Osijek (Croatia) during a three-year period (1993-1995) and involved 22 soybean genotypes. Mean values, variation coefficients, correlation coefficients and path coefficients were estimated for grain yield components, grain yield, protein and oil content in grain. The variation coefficient was low for the following traits: oil and protein content in grain, seed yield/plant, number of nodes/plant and seeds number/plant. Phenotypic path coefficients indicated a very strong positive direct effect of seeds number/plant and seed yield/plant on grain yield. The results of biometrical analyses showed that the direct selection on higher number of seeds/plant and higher seed yield/plant would result in greater genetic advance in grain yield.