ALLELOPATHY OF SHOWY RATTLEBOX DECOMPOSITION ON THE COMMON BEANS IN NO-TILL

Abstract

This study aimed to identify and quantify the phenolic compounds in soil covered with showy rattlebox (Crotalaria spectabilis Roth) at different decomposition times, followed by the sowing of common beans (Phaseolus vulgaris L.) and to determine the effects of these times on the emergence and vigor of the subsequent crops. Common beans were sown at intervals of 0, 10, 20, and 30 days after the deposition of showy rattlebox biomass. Phenolic compounds in the soil were analyzed using ultra-performance liquid chromatography (UPLC). The evaluated parameters for common beans included emergence, emergence speed index, chlorophyll a and b, plant height, leaf area, and dry mass. Results showed that C. spectabilis decomposition increased the concentration of epicatechin and resveratrol in the soil and catechin levels decreased. The showy rattlebox presence, independent of decomposition time, increased the plant height and dry mass of common beans. The shortest interval (0 days) between showy rattlebox biomass deposition and common beans sowing resulted in the highest rates of emergence and vigor.