Relationships Among Traits Using Correlation, Principal Components and Path Analysis in Safflower Mutants Sown in Irrigated and Drought Stress Condition

摘要

Safflower Carthamus tinctorius comes from Asteraceae family. Safflower is annual plant and used as oil and forage crop. In this research the seeds of Zarghan 279 as a winter variety was irradiated by Gamma ray in 80, 100, 150 and 200 Gy and sown in farm. The mutants after M5 generation grown in irrigated and drought stress condition in farm. The results indicated that differences among mutants for the height, capitulum diameter, number of seeds in capitulum, capitulum weight, days to 50% flowering, days to maturity and yield were significantly deferent in irrigated and drought stress condition. There were not significant differences between oil content and number of capitulum in two condition. On the basis of correlations between principal components and original traits, a classification was made to observe the relation between different traits. It was observed that for the first principal component, in irrigated condition height, stem diameter, capitulum diameter, number of seeds in capitulum, capitulum weight, oil content and days to maturity and in drought stress condition capitulum diameter, number of seeds in capitulum, 100 seeds weight, oil content and days to maturity had positive correlation between themselves i.e., varies in the same aspect. Path analysis suggested that in irrigated condition number of seeds in capitulum, 100 seeds weight and stem diameter and in drought stress condition number of seeds in capitulum, 100 seeds weight, days to 50% flowering and capitulum diameter had greatest positive direct effects, capitulum weight had greatest negative direct effect on seeds yield.