GROWTH OF PRIMARY LEAVES OF BEANS (PHASEOLUS VULGARIS L.) UNDER SUBOPTIMAL TEMPERATURES

Abstract

In a series of 14 tests, seedlings of 60 cultivars of the common bean (Phaseolus vulgaris L.) were assessed for growth rate at a suboptimal temperature of 10 C. Seedlings were grown in a growth cabinet, and the leaf area growth rate (LAGR) was determined from measurements of the primary leaf before and after treatment. LAGR differed significantly between selected low temperature-tolerant cultivars of similar seed weight. However, for all varieties tested, LAGR and seed weight were significantly correlated. It was concluded that several of the bean accessions such as P.I. 136701 and the cv. Limelight possessed a high degree of tolerance to suboptimal temperatures during early leaf growth and that this character could be used effectively in a breeding program.