Investigating the correlation and cause and effect relationships of leaf yield and some important agronomic traits in basil genotypes under different drought stress conditions
Subject Areas : Developmental biology of plants and animals , development and differentiation in microorganismsMehdi Rahimi 1 , Mojtaba Mortazavi 2
1 - Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran.
2 - Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran.
Keywords: Leaf, regression analysis, path analysis, correlation,
Abstract :
Basil is one of the important plants belonging to the mint family, which is used as a medicinal plant, spice, and also as a fresh vegetable. In order to study the relationship between leaf yield and agricultural traits, 22 basil genotypes were evaluated on the basis of split plot design based on randomized complete block design with three replications in pots under field conditions. The main plot included drought stress in three levels (normal, moderate and severe stress) and the subplot included genotype (22 levels) and agricultural traits were measured. Correlation of traits in all three conditions showed that leaf yield had a positive and significant correlation with the traits of stem fresh weight, number of leaves, length and width of leaves. Considering the leaf yield as a dependent variable and performing a stepwise regression analysis in normal conditions (stem wet weight, number of leaves and leaf width in the first stage, respectively), moderate drought stress conditions (stem dry weight in the first stage) ) and severe drought stress conditions (stem wet weight in the first stage) were entered into the model and the model was significant at the level of 1%. Path analysis showed that stem wet weight in normal conditions, stem dry weight in moderate stress condition and stem wet weight in severe stress condition had the highest direct and positive effect on leaf yield. Therefore, the most important traits as a selection index for improving leaf yield werestem fresh weight, leaf number, leaf length and width, respectively.