Impact of irrigation on rice production in midland region, Northern Vietnam

The study found that the used level of fertilizers and pesticide were higher in fully irrigated farms than that in partially irrigated farms. While, used labor in partially irrigated farms was lower than in fully irrigated farms. Average yield of rice, net family income of rice production in fully irrigated farms were higher than that in partially irrigated farms at significant level. The regression result of production estimated functions showed that coefficients of labor, fertilizers had a positive effect relative to rice production. The effect of pesticide on rice production was positive in partially irrigated farms but negative in fully irrigated farms. Pre-harvest labor, organic manure and nitrogen had high significant effect on rice yield in fully irrigated farms. While, potassium become more important in the partially irrigated farms. The MLE method was chosen to estimate frontier function. Analyzing results indicated that the gap between average and frontier yield is very small, potential for increasing rice yield is limited if farmers apply current technology in the fully irrigated farms. In the partially irrigated farm's case, frontier function envelopes average function. Study also found that average technical efficiency of fully irrigated farms was higher than that of partially irrigated farms. Regression results showed that seed quality, fertilizer, pesticide application skill and education level of household head had a high significant effect on technical efficiency and inefficiency, respectively. Irrigation had a positive effect relative to technical efficiency, and had a high significant in partially irrigated farms. In summary, analyzing results demonstrated that there are significant difference in production level, used inputs, productivity and technical efficiency between fully irrigated farms and partially irrigated farms. The research also showed factors affecting technical inefficiency of farms in the Midland region, Northern Vietnam