Rice-Common bean rotation under splinker irrigation: effects of row spacing, fertilizer and cultivars on rice yield and nutrient uptake

Abstract

Effect of row spacings (20, 35, and 50 cm), fertilizer levels (250, 400, and 550 kg/ha of formula 4-30-16), cultivars (Rio Paranaíba, Araguaia, CNA 6874, and CNA 6889), and the residual effect of previous common bean crop fertilization (300 and 500 kg/ha of 4-30-16) were studied, during four years, on the grain yield and nutrient uptake of rice planted in rotation with common bean under center pivot. The favorable upland rice lines CNA 6874 and CNA 6889 were replaced by CNA 6881 and CNA 6891, from the second year onwards. Effect of rice crop fertilization on yield varied with cultivar. The previous common bean crop fertilization affected only grain yield of cultivars Rio Paranaíba and Araguaia in the second year. The yield increased as the fertilizer level increased. Favorable upland rice lines showed higher yield at 20 cm row spacing. The same occurred with traditional upland cultivars when stress conditions limited their development. Under non-stress conditions, these cultivars showed higher yield at 50 cm row spacing. Higher nutrient uptake occurred at 20 cm row spacing and with CNA 6881 and CNA 6891 lines.