Abstract:

Jiangxi Province has begun the introduction of japonica rice from north China since 2009, and promoted the project of ‘japonica rice replacing indica rice’. In order to verify the yield potential of rice under the project, and explore the method of fertilizer reduction and efficiency increase of japonica rice, the experiment of late-rice yield potential and fertilizer reduction and efficiency increase of japonica rice was carried out in 2016 in Jingdezhen City of Jiangxi Province. The results showed that under the same fertilization and harvesting conditions, the yield of japonica rice variety ‘Yongyou 1538’ increased by 1450 kg/hm² (16.06%) compared with that of indica rice ‘Yueyou 9113’, because japonica rice had more grains per panicle. The results also showed that, compared with the farmers’ conventional fertilization method, the recommended fertilization method 2 could save nitrogen, phosphorus and potassium nutrient by 123.9 kg/hm² (20.31%), increase rice yield by 483.75 kg/hm² (4.67%), save cost and increase efficiency by 1765.35 yuan/hm² (7.87%), and the effect of increasing income reached a significant level. The recommended fertilization method achieved higher yield by promoting grain setting and increasing the number of grains per panicle. In conclusion, japonica rice has obvious yield increase advantage compared with indica rice, and the recommended fertilization method is more efficient than farmers’ conventional fertilization method. The recommended fertilization method is more reasonable in nitrogen, phosphorus and potassium coordination and fertilization time at tillering and booting stages, and the effect of late fertilization time at booting stage of japonica rice is much better.

Key words: rice, japonica rice replacing indica rice, yield potential, fertilizer reduction and efficiency increase, fertilization method