In this study, in order to realize effects of cultivation methods and nitrogen application on the rice false smut (RFS) and yield of double cropping late japonica
rice in Jiangxi Province, the effects of different cultivation methods and nitrogen application on the yield, infected panicle rate (IPR) and disease index (DI) of RFS of late-season rice were studied. Four common late Japonica rice varieties in Jiangxi Province were used as experimental materials, including ‘Yongyou 538’‘Xiaoyechishu’‘Yongyou 1538’ and ‘Yangchan 1601’. Three sowing and transplanting time treatments (T1, T2 and T3), five transplanting densities treatments [3.75×105(A1), 3.22×105(A2), 2.81×105(A3), 2.5×105(A4) and 2.25×105 hole·hm-2(A5)], five nitrogen application treatments [0(N1), 165(N2), 225(N3), 285(N4) and 345 kg·hm-2 (N5)], and five treatments of nitrogen application ratio [the ratio of base fertilizer, tillering fertilizer and panicle fertilizer was 6∶3∶1 (M1), 5∶3∶2 (M2), 4∶3∶3 (M3), 3∶3∶4 (M4) and 2∶3∶5 (M5)] were set up. The results showed that the early sowing and planting time could significantly reduce the IPR and DI of RFS, and effectively improve the yield of rice. The damage degree of RFS was increased with the increase of transplanting density from 2.25×105 to 3.75×105 hole·hm-2. The yield were first increased and then decreased with the increase of transplanting
density. When the transplanting density of rice was small (the transplanting densities of ‘Yongyou 538’‘Yongyou 1538’ and ‘Yangchan 1601’ were lower than 2.5×105 hole·hm-2, and that of ‘Xiaoyechishu’ was lower than 2.25×105 hole·hm-2), the IPR and DI of RFS were small. In the range of nitrogen application rate in this study, the IPR and DI of RFS were increased significantly with the increase of nitrogen application rate, and the overall yield were increased first and then decreased with the increase of nitrogen application rate. In the early stage, the application of nitrogen fertilizer had little effect on the occurrence of RFS, but the late application of nitrogen fertilizer resulted in serious RFS. The yields of all late japonica rice varieties reached the highest when the total nitrogen application rate was 225 kg·hm-2 and the ratio of base fertilizer∶tiller fertilizer∶panicle fertilizer was 4∶3∶3. Therefore, it was beneficial to reduce the damage degree of RFS of late japonica rice in Jiangxi Province and improve the yield of rice.