南充油菜菌核病发生流行成因分析及综合防控措施研究

Analysis on Field Occurrence Reason and Integrated Control for Rape Sclerotinia stem rot in Nanchong

对1998—2008年油菜菌核病田间系统调查和病情普查分析表明,南充市油菜菌核病具有单年流行的菌源量基数和长达18～25天的病菌孢子最适侵染期,而适宜的气象条件则是菌核病重发的决定性因素。根据11年来2—4月的气象因子,结合最终茎秆发病面积比、最终茎病株率和最终病情指数建立了3个数学模型,并取得较好回检效果。利用稻草覆盖、适当调整播栽期等轻简化栽培控病措施,对油菜菌核病的综合防治效果可达50%以上;用2次50%多菌灵100g/667m2防效可达85%以上,菌核病在南充尚未对多菌灵产生明显的抗药性。

Based on the systematic survey and disease investigation of oilseed rape sclerotiniose from 1998 to 2008 in Nanchong,the single-year prevalence could be caused by the cardinal number of sclerotia from Sclerotinia sclerotiorum,and the optimum infection period of ascospore was 18-25 days.The suitable weather conditions were the decisive factors of the serious disease.According to the meteorological factors in the past eleven years from February to April,three mathematical models had been established and achieved good test results. The mathematical models respectively related to the area ratio of ultimate incidence in stem, the diseased plant rate of stem disease and the final disease index. Utilizing lightened and simplified disease-control cultivation measures such as straw mulching, appropriate adjustment of sowing and transplanting period, the effect of integrated control on oilseed rape sclerotiniose could reach more than 50%. The drug-resistance of Sclerotinia sclerotiorum to carbendazim wasn＇t obvious yet on local. When applied with 50% carbendazim at 100 g/667m2 twice in field, the control effect was over 85%.