RT - Journal Article T1 - Relationships Between Traits and Path-coefficient Analysis for Bulb and Seed Yield Iranian Landraces of Onion (Allium Cepa L.) JF - JSTNAR YR - 2002 JO - JSTNAR VO - 5 IS - 4 UR - http://jstnar.iut.ac.ir/article-1-83-en.html SP - 53 EP - 69 K1 - Onion K1 - Genotypic and phenotypic correlations K1 - Path analysis K1 - Stepwize Regression. AB - In order to determine the relationships among the different traits of onion and to study the direct and indirect effects of these traits on bulb and seed yield, an experiment was conducted in 1998 at the research farm of Isfahan University of Technology. Results showed that phenotypic and genotypic correlations were similar and bulb weight showed the highest and lowest coefficients of correlation with bulb diameter and number of days to emergence, respectively. Results of stepwise regression analysis showed that leaf width at 25% of its length from the neck, leaf length, and leaf dry weight were the best estimators for leaf area bulb diameter, bulb length, plant height and number of days to maturity were the most important determining characters for bulb yield variation. Number of fertilized florets was the best determinator of seed yield and bulb weight, while diameter and volume were the best describing characters for the number of meristems on the basal plate. Path-coefficient analysis revealed that bulb diameter showed the highest direct positive effect on bulb yield and the indirect effect of plant height through bulb diameter on it was of prime importance. Number of fertilized florets per plant and number of inflorescence per plant through the number of fertilized florets showed the highest direct and indirect effects on seed weight, respectively. LA eng UL http://jstnar.iut.ac.ir/article-1-83-en.html M3 ER -