Green manure with fabaceous species in monoculture or intercropped with corn in the organic cultivation of pumpkin in succession

The aim of this study was to evaluate, in three consecutive cycles, the phytotechnical performance of herbaceous fabaceous plants cultivated in monocropping or intercropped with corn and the pumpkin productivity in succession. The statistical design was of randomized blocks in a factorial arrangement 2 (monocropping or intercropping) x 3 (fabaceous species) + 1 (corn monocropping). The treatments consisted of gray velvet bean monocropping; gray velvet bean intercropped with corn; sunn hemp monocropping; sunn hemp intercropped with corn; jack bean monocropping; jack bean intercropped with corn and corn monocropping. After cutting the fabaceous and corn, Itapua 301 pumpkin cultivar was planted. The authors verified that fabaceous monocropping reached higher dry biomass productivities, especially sunn hemp in the first and second years and provided greater accumulation of N, P and K. In the first year, fabaceous pre-cropping, regardless of the arrangement, provided an increase in pumpkin productivity up to 165.87% higher comparing with corn pre-cropping, whereas in the second and third years, no pumpkin production associated with corn monocropping was observed. The three Fabaceae species showed potential to be used as green manure in pumpkin growing when compared with corn pre-cropping.