Influence of soybean management decisions on the subsequent rice crop's response to nitrogen

Abstract

AbstractLittle is known about the effects of soybean [Glycine max (L.) Merr.] management practices on the success of the subsequent rice (Oryza sativa L.) crop. A study was initiated to determine how rice was affected by the preceding soybean crop's maturity group (MG) and planting date when grown in rotation on silt loam and clay soils. Optimum and late soybean planting dates and MGs (3.5, 4.7, 5.4, and 5.6) were followed by a rice crop. The results differed by soil texture, with the planting date and MG selection of the previous soybean crop more influential to the rice crop produced on a silt loam soil than a clay soil. Rice grown on a clay soil produced a higher grain yield when following a 5.4 MG soybean, whereas the planting date of a previous soybean crop influenced the soil‐N credits measured at rice emergence. On a silt loam soil, the interaction of both planting date and MG of the previous soybean crop influenced the maximal grain yield achieved by the rice crop. When soybean is planted during an optimum planting date, soybean MG has little effect on the successive rice crop. However, when the soybean crop is planted late, a determinate MG should be selected to achieve the highest rice crop total N uptake, maximal grain yield, and reduce the rate of fertilizer‐N needed to achieve 95% relative grain yield. Management techniques should be considered when implementing a soybean–rice rotation to maximize rice grain yield and overall farm profitability.