Measuring the impact of stress‐tolerant rice variety adoption: Evidence on input use and yield in Nepal
研究了尼泊尔农户在非干旱年份采用耐逆水稻品种如何影响化肥、农药等投入品使用和产量，发现采用该品种会“挤入”更多投入，并带来与高产品种相当的增产效果。
Abstract New agricultural technologies, such as stress‐tolerant rice varieties (STRVs), that reduce yield risk can modify farmers’ production decisions. This article explores how STRV adoption affects farmer decision‐making and productivity in Nepal in a non‐drought year. STRVs are bred to be high‐yielding and tolerant to climate shocks such as drought. To assess the effect of input measurements on treatment effects, we collected information from 900 households on STRV adoption and input use. We also conducted a survey experiment in which half of sampled households were randomly assigned to answer additional, more detailed questions on agricultural inputs. Farmers apply more total chemical fertilizer, pesticides, early‐season chemical fertilizer, and land preparation labor to plots planted with STRVs compared to traditional varieties (TVs). Detailed input data enhances our understanding of how this “crowding‐in” effect of STRV adoption on input use compares with other high‐yielding varieties. While farmers increase application of a subset of these inputs on other improved variety types such as hybrids, results suggest that crowd‐in effects are most consistent for STRVs. In the absence of drought, STRVs also provide a similar yield boost and yield variance reduction over TVs compared to other, non‐stress tolerant improved varieties. Results suggest that improved varietal adoption, and STRV adoption in particular, can improve household productivity and modernization of agriculture.