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.

为明确栽培方式和氮肥运筹对江西双季晚粳稻产量和稻曲病发生的影响，以‘甬优538’‘小叶迟熟’‘甬优1538’和‘扬产1601’四种江西省常见晚粳稻品种为试验材料，对不同栽培方式和氮肥运筹对晚粳稻的产量、稻曲病病穗率和病情指数进行了研究。设置3个播栽期处理\[7月3日（T1）、7月10日（T2）和7月17日（T3）]、5个移栽密度处理\[3.75×105（A1）、3.22×105（A2）、2.81×105（A3）、2.5×105（A4）和2.25×105穴·hm^-2（A5）]，5个施氮量处理[ 0(N1)、165

(N2)、225(N3)、285(N4)和345 kg·hm^-2 (N5) ]、5个氮肥施用比例处理 [基肥∶分蘖肥∶穗肥比例分别为6∶3∶1 (M1)、5∶3∶2 (M2)、4∶3∶3 (M3)、3∶3∶4 (M4)和2∶3∶5 (M5) ]。结果表明，播栽时间提前可显著降低稻曲病的病穗率与病情指数，且有效提高水稻产量。稻曲病的危害程度均随移栽密度增加而上升，产量随着移栽密度的增加呈先上升后下降的趋势。当水稻的移栽密度较小时（品种‘甬优538’‘甬优1538’和‘扬产1601’的移栽密度低于2.5×105穴·hm^-2、品种小叶迟熟低于2.25×105穴·hm^-2），稻曲病的病穗率和病情指数较小。在上述施氮量范围内，稻曲病病穗率与病情指数随着施氮量的增加而显著升高，产量随着施氮量的增加整体呈先上升后下降趋势。不同时期施氮比例方面，前期施氮量对水稻稻曲病发生的影响较小，而后期偏施氮肥的稻曲病发病严重。所有晚粳稻均在施纯氮量为225 kg·hm^-2、基肥：分蘖肥：穗肥为 4∶3∶3时，水稻的产量达到最高。因此，适当优化栽培方式和氮肥运筹有利于降低江西晚粳稻稻曲病的危害并提高水稻产量。