Benefit of using biodegradable film on rice grain yield and N use efficiency in ground cover rice production system

A ground cover rice production system (GCRPS) has been reported to reduce the consumption of irrigation water while increasing grain yield and water use efficiency in regions where water and temperature are limiting factors for rice production. However, all fertilizer must be applied in a single basal dose before the soil surface is covered by plastic film in GCRPS resulting in excessive vegetative crop growth and nitrogen deficiency during the reproductive stage. Furthermore, a severe drawback of GCRPS is soil and water pollution from residuals polyethylene film used for ground cover. A two-year field experiment was conducted using biodegradable film together with treatments comparing all basal application of N with application of N as three splits and a single basal fertilization of urea plus manure. We examined N uptake and crop growth from transplanting harvest, rice grain yield, yield components, dynamics of tillers and shoot dry matter, and N recovery efficiency. Compared to basal application of all N fertilizer in GCRPS, split application of N or a basal combination of urea plus manure in conjunction with the use of biodegradable film 1) significantly increased rice grain yield, number of productive tillers, and spikelets per square meter; 2) improved crop growth rate and N uptake rate from panicle initiation to maturity; and 3) significantly increased agronomic efficiency of N fertilizer and recovery efficiency of N in grains. Our results highlight that using biodegradable film instead of standard plastic film allows for split application of fertilizers, which increases yield and N use efficiency as well as significantly reduce environmental pollution with plastic film in GCRPS. (C) 2016 Elsevier B.V. All rights reserved.