ln the research, an empirical analysis was performed on production per-formance and influential factors of rice in Changsha County and Liling City. The re-sults showed that production scale has been closely linked to age and education level of farmers. The larger scale, the higher comprehensive performance, but rele-vant efficiency tends to be lower. Sowing area and yield per unit area are major in-fluential factors of production performance of double-cropping rice, but the rest influ-ential factors are different upon production scale. Final y, developmental strategies are proposed for development of double-cropping rice.
The research conducted investigation and survey on 186 farm households in 2014 and carried out economic evaluation on ＂planting three to produce four＂ highyielding project of super hybrid rice. The results showed that the project of ＂planting three to produce four＂ performed significantly in terms of increasing yields and incomes. For example, per unit area yield of one-season late hybrid rice and middleseason hybrid rice proved the highest, and net income from middle-season rice in Longhui was the highest. It is obvious that to increase per unit yield is key for improving net incomes and to reduce machine fees and worker fees is crucial for decreasing fees.
The research explored productive efficiencies of main crops in the decade in Hunan by nonparametric DEA method and the results showed that net output value and net-profit rate of potato and sweet potato were extremely higher than those of rice and maize, and comprehensive efficiencies from high to low were potato, rice, sweet potato and maize. It is recommended that scales of rice, maize, and sweet potato should be reduced to certain extent and the scale of potato pro- duction extended. Besides, direct fee and labor cost should be lowered as much as possible to improve net-profit rate, accelerate crop S＆T development and improve grain productive efficiency.
