文章摘要：
BACKGROUND: In neutral or alkaline soils, iron (Fe) easily forms insoluble complexes, which makes it diffificult for plants to utilize Fe in the soil for nutrition. Polyester sulfur-coated urea (PSCU) is a novel controlled-release fertilizer widely used in China and some foreign countries, and it has been proven that sulfur fifilm from controlled-release fertilizers can signifificantly improve the activation of Fe and other elements in the soil. However, few studies have focused on the effects of PSCU application on Fe accumulation in rice grain in alkaline soils.
RESULTS: Both our fifield and pot experiments proved that PSCU application could signifificantly improve rice grain yield and Fe concentration in brown rice in alkaline soil. This effect differs with different types of alkaline soils (i.e. medium-saline, sandy soil and/or silt soil). PSCU is released slowly, and the release rate is different in different alkaline soils. Rice shoot nitrogen (N) uptake was signifificantly enhanced with PSCU application.
CONCLUSION: The results suggested that PSCU application in alkaline soils could signifificantly enhance brown rice Fe concentration and production. This effect differed with different kinds of alkaline soils. The study identifified some effificient fertilizers to
improve the Fe status in alkaline soils.