Comparison of Typhoon Damage to Crotalaria juncea, C. spectabillis and Sesbania rostrata

Abstract

This study investigated typhoon damage due to strong winds and saltwater splash in three green manure crops (Crotalaria juncea, C. spectabillis and Sesbania rostrata) in Okinawa, assessed as stem breakage, leaf wilt, and survival at harvest. Stem breakage due to strong winds was significantly higher in C. juncea and leaf wilt due to saltwater splash was significantly higher in C. juncea and C. spectabillis than in S. rostrata, which had almost no damage. Some damaged C. juncea plants regenerated, but C. spectabillis did not, and most plants withered before July 21st after passage of the typhoon 10. At harvest, the plant survival rate was 49% in C. juncea and 87% in S. rostrata. Thus, S. rostrata was the most resistant to strong winds and saltwater splash. It had a somewhat higher biomass and N content than C. juncea but a comparable P content. The amount of regrowth per remaining plant was greater in C. juncea than in S. rostrata owing to the greater loss of C. juncea plants, and the CN ratio was significantly higher in C. juncea stems, suggesting a decrease in the rate of stem decomposition.