Ground cover rice production system increases yield and nitrogen recovery efficiency

Abstract

Rice (Oryza sativa L.) production faces a worldwide challenge of severe water scarcity. The ground cover rice production system (GCRPS) is one alternative to the paddy system, using plastic-film covering and less irrigation water. As contradictory yield performances occurred throughout different regions, a general evaluation of GCRPS was seldom reported. Therefore, a 7-yr experiment was conducted in a mountainous area of the Hubei Province from 2003 to 2009. the paddy system and GCRPS were compared with 0 and 150 kg N ha-1, where crop growth, yield, plant N uptake, and soil C and N were measured to evaluate the adaptability, stability, and sustainability of GCRPS. Under GCRPS, grain yield was significantly higher than under the paddy system during the 7-yr period. Additionally, the interannual difference in grain yield under GCRPS was significantly lower than under the paddy system. Furthermore, vegetative growth of GCRPS plants was improved with a sufficient N supply, while reproductive growth was limited with N reduction, which led to low number of spikelets and filled grains. Soil organic C and total N (0-20-cm soil depth) were both significantly lower under GCRPS than paddy cultivation, while N fertilization slightly reversed organic C and N reductions. Hence, GCRPS is highly adoptable and stable in typical paddy areas where water scarcity and low temperature occur and high clay and organic matter contents prevail. Further research is needed to evaluate GCRPS in other related locations and to assess new techniques for achieving continuous soil N supply to the reproductive stage and increasing sustainability under GCRPS. Copyright © 2012 by the American Society of Agronomy.