Abstract:

Partially replacing chemical fertilizers by organic fertilizers can improve soil quality and fertility, which is conducive to the green and sustainable development of agricultural soil. In this study, to determine the appropriate proportion of organic fertilizers to partially replace chemical fertilizers in rice planting and achieve the chemical fertilizer reduction and efficiency enhancement, the early rice variety Zhongzu 18 was used for analyzing rice yield, rice quality, and plant traits. The results showed that compared with CK, fertilization significantly increased rice yield; compared with CF, the rice yield of 60M treatment was reduced considerably, and 45% was the maximum organic fertilizer replacement ratio that did not affect rice yield. Compared with CK, fertilization significantly increased the head rice rate, chalky grain rate, starch content and protein content; compared with CF, the head rice rate and starch content of rice in 60M treatment were significantly reduced, and 45% was the maximum organic fertilizer replacement ratio that did not affect rice quality. Compared with CK, fertilization significantly increased plant height, tiller number, effective panicle number, panicle number, and panicle length; compared with CF, organic fertilizer substitution did not affect rice plant growth traits. Compared with CK, fertilization significantly changed the nitrogen, phosphorus, and potassium content of the plants; compared with CF, the nitrogen and potassium content of the plants in the 60M treatment was significantly reduced, and 45% was the maximum organic fertilizer substitution ratio that did not affect plant nutrients. In summary, compared with the application of chemical fertilizers, the 60% nitrogen substitution treatment of organic fertilizers could have a greater adverse effect on rice yield, rice quality, and plant traits. To achieve the purpose of reducing application quantity of chemical fertilizers and increasing their efficiency, 45% of organic fertilizers and other nitrogen substitutions for chemical fertilizers are the best substitution ratios for rice field cultivation.

Key words: organic fertilizer, equivalent nitrogen replacement, rice yield, rice quality, plant traits