Impact of hybrid rice expansion on rice production since 1980s: from a historical input and output data aspect in China

In China, hybrid rice cultivation has been continuous for over 40 years. There have been significant advances in the breeding of dwarf varieties, three-line system, two-line system, and super hybrid rice. The development of hybrid rice has resulted in dramatic increasing in rice yields, which make it one of the most important technologies for China's food security. Previous researchers place significant emphasis on the technical evaluation of enhanced rice cultivars. China, as a significant producer of hybrid rice, lacks a systematic evaluation on the contribution of hybrid rice on the grain output, and just depends on a basic comparisons of yield differences between hybrid and conventional rice, without considering the input difference and other improvement for rice cultivation. The purpose of this study is to evaluate and quantify the impact of hybrid rice to rice yield under controlled input factors and other technical improvements. We collected input-output data on rice production and the extension area of the most important hybrid rice types from 30 provinces in China from 1983 to 2009. Utilizing a stochastic frontier production function, the effect of hybrid varieties on rice yield was analysed. According to the findings of this study, expanding the cultivation area of hybrid rice correlates to an increase in rice yield. The rice yield rises by 5.7% for each percentage point increase in the adoption rate of hybrid types. After 2000, however, the impact on yield has gradually diminished and become inconsequential. The adoption rate of hybrid types has a differential effect on rice yield across cropping seasons. The adoption rate has a substantial effect on the output of mid-season and late-season rice but has little effect on the yield of early-season rice. After dissecting the causes of rice yield increase, it was determined that hybrid variety adoption contributed 10.06 percent to the enhancement of hybrid rice production.