2022 Volume 91 Issue 1 Pages 1-8
Sesbania cannabina and S. rostrata are grown as green manure crops in Okinawa, Japan. The former sets seeds early and poses a potential weed problem. The latter does not. We compared plant growth and nutrient uptake between the species. S. rostrata showed more vigorous growth in pots than S. cannabina in Kunigami Marji (red soil), Shimajiri Marji (dark red soil), and Andosol at 45 days after sowing. Both appeared to have low P tolerance, because P fertilization had little effect on their growth in Kunigami Marji. The Mg content was higher in S. rostrata, but other nutrient contents tended to be similar or slightly higher in S. cannabina. In the field, S. rostrata showed significantly more vigorous growth than S. cannabina at 87 days. The pods accounted for about 1/3 of the aboveground weight in S. cannabina. The total aboveground weight (including pods) was also large in S. rostrata. The P contents in the aboveground parts (including pods) were similar, but the N, K, Ca, and Mg contents were larger in S. rostrata. These results suggest that S. rostrata would be as effective as S. cannabina as a green manure crop.
