Factors explaining variability in rice yields in a rain-fed lowland rice ecosystem in Southern Cambodia

Publication date: Available online 8 June 2016 Source:NJAS - Wageningen Journal of Life Sciences Author(s): Proyuth Ly, Lars Stoumann Jensen, Thilde Bech Bruun, Andreas de Neergaard There is a growing body of literature documenting higher productivity of the System of Rice Intensification (SRI) than conventional practices; however, few studies have been conducted to explore the factors explaining this higher productivity. This paper investigated key factors influencing yields in a rain-fed lowland rice ecosystem in Cambodia under farmer’s SRI and conventional management practices (CMP). Rice yields from 70 plots with recorded management practices (36 plots under farmer’s SRI and 34 plots CMP) were measured. Composite soil samples (210 in total) were collected from the harvested plots and analyzed for physical and chemical properties. Stepwise multiple regression analysis was performed to identify important predictors explaining rice yield variability. Variables contributing significantly to yield variation included: number of cattle (access to farmyard manure [FYM]), farmer’s SRI practices, planting density and soil organic carbon (SOC). These four variables explained 39% of variance in rice yield. Keeping other variables constant, rice yields were increased by 14% (458kgha−1) by shifting from CMP to farmer’s SRI practices. The change of one unit in cattle (head), hill density (hillm−2) and SOC (gkg−1) results in an increase of rice yield by 5% (153k...
Source: NJAS Wageningen Journal of Life Sciences - Category: Biology Source Type: research