Potential uses of sicklepod ( Cassia obtusifolia)

Abstract

Sicklepod ( Cassia obtusifolia) is a leguminous weed species that has become a severe problem in soybean production throughout the Southern United States. Economic incentives, such as premiums for low levels of foreign matter from cleaning soybeans prior to sale, could generate a large source of sicklepod seed in that area. This study was undertaken to evaluate C. obtusifolia seed for potential applications. As much as 41% of the seed was extractable. Some extracts were strong inhibitors of wheat, velvetleaf and sicklepod root growth, causing discoloration of the root meristems in a manner similar to that caused by naphthoquinones such as juglone and plumbagin. Some extracts increased weight gain in fall armyworm ( Spodoptera frugiperda) causing them to grow to 50–100% larger than controls in a 7-day trial. Survival of Columbia root-knot nematode ( Meloidogyne chitwoodi) in the soil was inversely correlated to the amount of ground whole sicklepod amendment. No phytotoxic effects of the meal amendment on tomato plants or inhibition of germination for several crop seeds was observed at the levels tested.