Abstract

Effect of soil moisture stress on the growth of Corchorus olitorius L. was investigated using two varieties in the glass house during summer at Tokyo, Japan. Smaller growth was showed in light moisture stress (60 - 50%) and acute moisture stress (40 - 30%) comparing to that of field capacity soil moisture, however the growth in light and acute moisture stress was not much different fromeach other. Plant height was stunted under soil moisture stress condition. It was caused by shorter inter-nodes. Soil moisture stress affected the growth of inter-nodes. Both varieties of C. olitorius were able to grow under heavy soil moisture stress condition (less than 30% of field capacity soil moisture, primary wilting pointof plants). The C. olitorius has tolerance to soil moisture stress. Application ofabscisic acid was not effective for the growth of C. olitorius under soil moisture stress condition, because of its tolerance to soil moisture stress. Viscosity of branches in both varieties was larger in heavy soil moisture stress condition. The viscosity in C. olitorius seems to be related with soil moisture stress.

Key words: Abscisic acid, mucilage, soil moisture, viscosity, yield.