Parental Line Selection for Cucumber Hybrid Seed Production by Principal Components Analysis

Abstract

Principal components analysis involves a mathematical procedure that transforms a number of possibly correlated variables into a smaller number of uncorrelated variables called principal components. Principal components analysis was performed using downy mildew infection percentage; downy mildew resistance score; days to harvest; number of nodes per plant; plant length; number of branches per plant; days to first male flower appearance; days to first female flower appearance; cotyledon bitterness; fifth leaf bitterness that correlated with fruit bitterness; first midrib length; second midrib length; third midrib length; first node length; early, nonmarketable, marketable, and total yields; fruit shape; marketable yield percentage; simple weight index; overall performance; fruit set percentage; distance to first fruit; number of fruit on main branch; fruit bitterness; fruit end bitterness; fruit color; and seed cell size. A three-way cross between [(115*118)*502] lines could produce a hybrid that is early to harvest, resistant to downy mildew, and with high yield.

Keywords:

• Cucumis sativus
• Downy mildew resistance
• Earliness
• Yield
• Vegetative growth