Correlation and Path Coefficients Analysis between Morphological Characteristics and Conservable Grain Yield of Sweet and Super Sweet Corn (Zea Mays L. var. Saccharata) Varieties

In order to evaluate the effects of planting methods on morphological traits, yield and yield components of sweet and super sweet corn varieties, an experiment was conducted at Khorasan Razavi Agricultural and Natural Resources Research center, Mashhad, Iran in 2012. In this research three planting method (one row raised bed, two row raised bed and furrow planting), sweet corn varieties (Chase, Temptation, KSC403su and Challenger), was laid out in factorial design based on randomized complete block design with three replications. The results of this study showed that different planting methods had significant effects on morphological traits such as plant height, ear height, ear leaf area, relative growth rate, 1000-grain weight, ear diameter, number of ear per plant, grain depth, conservable grain yield and plant harvest index at the P<.01 level. Moreover, results showed that different varieties had significant differences among traits such as the number of ear per plant, ear diameter, grain percentage, cob percentage, 1000-grain weight, conservable grain yield and harvest index. The results of correlation coefficient analysis also indicate highly significant correlation between conservable grain yield and all measured traits except for plant height, ear height, relative growth rate, ear diameter, and the number of ear per plant at the P<.01 level. The results of stepwise regression method analysis and path coefficient showed that conservable grain yield was affected by three traits of 1000-grain weight, ear diameter and number of ear per plant. Furthermore, these three traits indicate high and significant regression coefficient on conservable grain yield, respectively. Results of path coefficient analysis indicated that all traits positively affect conservable grain yields. Therefore, the measured traits like 1000-grain weight, ear diameter and the number of ear per plant had the highest direct effect on conservable grain yield. According to this study, selection for 1000-grain weight, ear diameter and number of ear per plant can led to improve conservable grain yield.