Evaluation and Classification of Low Fertility Tolerance of Main Rice Varieties in Guangxi

【Objective】The present study was to evaluate the ability of low fertilizer tolerance of major rice varieties in Guangxi and to screen nutrient-efficient rice varieties for production and application.【Method】48 major rice varieties were selected for field experiment and four treatments were set, i.e. 1/3 standard nitrogen fertilization, no phosphorus fertilization, no potash fertilization and standard fertilization. The ability of low fertilizer tolerance of rice varieties was evaluated based on relative yield (ratio of rice yield under low fertilizer conditions to that under standard fertilizer conditions). 【Result】 The relative yields of the three treatments (1/3 N application, no P application and K application) were 0.89, 0.88 and 0.93, respectively, and there were significant differences among varieties. Based on the clustering analysis of relative yield of varieties, 48 rice varieties could be grouped into three categories according to their tolerance to low nitrogen, phosphorus and potassium, respectively. Among all varieties , Guangliangyou 1598, Guiliangyou 2, Teyou 5,Teyou 582,Guifeng 2,Teyou 3813,Teyou 6135, Keliangyou 889, Zhongguangxiang 1, Yahangjinzhan had strong tolerance to low nitrogen, phosphorus and potassium simultaneously. 【Conclusion】There were significant differences in the tolerance to low nitrogen, phosphorus and potassium among different rice varieties in Guangxi. 10 of 48 varieties had strong tolerance ability to low nitrogen, phosphorus and potassium.