关键词: 枸杞树, 枸杞树, 果实, 枝条, 叶片, 产量, 氮磷钾吸收, 施肥量

Abstract: To screen resistant varieties of late japonica rice to rice false smut planted in Jiangxi province, and fungicides against rice false smut and its using technologies, the resistance of 27 introduction varieties of late japonica rice to rice false smut in Jiangxi Province was identified by natural infection, indoor toxicity of 10 fungicides against rice false smut was assayed by measuring mycelial growth rate, the efficacies of 10 fungicides against rice false smut and the effects of spray timing and times on the efficacies of 3 fungicides were conducted by field trials. Field test results showed that there were 3 high resistance varieties (Changjiang 32, Changyou No.5 and Chishou jingwu), 14 resistance varieties (Changjiang 19, etc.), 7 middle resistance varieties (Yongyou No.12, etc.) and 3 middle susceptible varieties ((Yongyou 15, etc.) among 27 tested varieties according to disease panicle rate for resistance evaluation index. There were 25 high resistance varieties (Changjiang 19, etc.) and resistance varieties (Yongyou 15 and Yongyou 15) according to disease index for resistance evaluation index. Bioassay results showed that the order of relative toxicity indexes, which 10 kinds of fungicides inhibited mycelium growth of rice false smut, were fenbuconazole(168.49), thifluzamide(111.08), azoxystrobin(107.84), epoxiconazole91.68), difenoconazole?propiconazole83.47), tebuconazole(42.34), prochloraz(21.51), hexaconazole(12.92), triadimefon(1.32) and Jinggangmycin A(1), respectively. The field tests revealed that the efficacy of thifluzamide (24% SC), fenbuconazole (24% SC), epoxiconazole (12.5% SC) and azoxystrobin (25% SC) against rice false smut were highest with panicle efficacy of 69.89%～74.33% and disease index efficacy of 69.16%～76.12% by the survey in late rice ripening (November 14th) according to spray with the recommended using dose in paddy field in heading, followed by difenoconazole?propiconazole (300g/L EC) and tebuconazole (43% SC) with panicle efficacy of 55.29%～59.31% and disease index efficacy of 59.84%～64.53%. The efficacies of hexaconazole (30% SC), triadimefon (15% WP) jingangmycin A (5% SP) and prochloraz (25% EC) were relatively poor, and those of their panicle were below 50% and those of their disease index were below 59%. The efficacies of fenbuconazole (24% SC), epoxiconazole (12.5% SC) and thifluzamide (24% SC) against rice false smut decreased with delaying spray timing at 7 d before heading, heading and 7 d after heading, with spray at 7 d before heading being the best, and with spray at 7 d after heading being the worst. The efficacies of 3 fungicides against rice false smut rose with increasing spray times with spraying once (at 7 d before heading), 2 times (at 7 d before heading and heading) and 3 times (at 7 d before heading, heading and 7 d after heading), which there was no significant difference between the panicle and disease index efficacies with spraying 2 times and 3 times. The panicle and disease index efficacies of fenbuconazole (24% SC) and thifluzamide (24% SC) with spraying 2 times and 3 times were significant better than that with spraying 1 time, and there was no significant difference between the panicle and disease index efficacies of epoxiconazole (12.5% SC)with spraying 2 times and 3 times and that with spraying 1 time. The result provides a basis for the breeding and application of resistance varieties of late japonica rice in Jiangxi province and chemical control against rice false smut.