【作者】 徐冬；

【导师】 李敏权；

【作者基本信息】 甘肃农业大学 ， 作物保护， 2010， 硕士

【摘要】 针对发生于甘肃省嘉峪关新城镇的洋葱基盘腐烂病的发生情况进行了调查,研究了该病的病原菌。同时初步研究了洋葱品种对基盘腐烂病抗病性,在室内进行了防治洋葱基盘腐烂病的化学药剂筛选,并在大田中进行了化学防治试验。1.洋葱基盘腐烂病的症状:发病初期下位叶黄化、萎蔫或弯曲,生育盛期洋葱鳞茎侧面呈软腐状腐败,后扩展到茎盘,严重的地上部全部萎蔫,茎盘变褐枯死。湿度大时鳞片间产生白色或灰白色霉状物。干燥条件下,病组织变紫死亡或枯死。该病原研究结果说明尖孢镰刀菌所占比例最大,为69.66% ,而茄病镰刀菌和串珠镰刀菌所占比例依次为21.99%和8.35%。室内平皿致病性测定结果表明,尖孢镰刀菌的病情指数为60.2,致病能力最强,成为引起洋葱基盘腐烂病的主要病原菌。2.用平皿法研究嘉峪关新城镇的10个洋葱主栽品种的抗病性鉴定。结果表明,各品种对洋葱基盘腐烂病的抗性间存在差异,对于尖孢镰刀菌从抗性表现上看牧童、金美F1为中抗(MR)品种,太阳格林、雄狮为中感(MS)品种,红色经典、红皮08、黄皮02、紫金505F1、红宝911F1为感病(S)品种,欧洲豹1号为高感(HS)品种。3.室内4种杀菌剂对病原菌的生长均有抑制作用,但不同药剂之间有差异。其中多菌灵、百菌清、恶霉福、施菌克对尖孢镰刀菌的有效中浓度(EC50)分别为69.58、158.12、143.13、6.03μg/mL,对茄病镰刀菌EC50分别为5. 87、152. 76、35. 75和70. 12μg/mL,对串珠镰刀菌EC50分别为49.53、2.11、4.48和126.61μg/mL。以施菌克的抑菌作用最为突出,多菌灵次之,百菌清最差。四种药剂的相关系数均在0.98以上,药剂浓度与抑制作用呈正相关。4.田间化学防治试验以7种农药为试材,在嘉峪关市新城镇进行洋葱田间化学试验,采用随机区组设计,重复四次。在收获期对各小区分别测定洋葱基盘腐烂病的发病率、病情指数、产量等指标进行综合评价。结果表明,防效较好的为15%阿维.毒EC 1500倍液、15%阿维.毒EC1000倍液,达到84.79%、81.11%。通过测产看出15%阿维.毒EC 500倍液、15%阿维.毒EC 1500倍液两处理增产效果明显,增产14.23%、8.54%, 40%辛硫磷EC 800倍液处理减产6.64%。90%敌百虫GR(0.6g)、40%,辛硫磷EC 400倍液、90%敌百虫GR(1.2g)三处理间产量无差异。更多还原

【Abstract】 The Basal plate rot of onion was surveyed in Xinchen Town, Jiayuguan City,Gansu Province. The pathogen that caused the disease were Fusarium oxysporum . Meanwhile, the resistance of different varieties to this disease was conducted and several fungicides were screened in the laboratory. And chemical control experiment was also maken in the field.F. oxysporum caused Basal plate rot of onion. The beneath leaves showed yellowing, wilting or bending in the early stage. The disease developed at the base of the bulb, causing it to become soft. A semi-watery decay progresses from the base of the scales upward.All of leaves overground became wilt seriously, and bulb scales discolored brown and died. Meanwhile, white and grey white mildew were found interscales when air became humidity. The diseased tissue became purple during the Basal plate condition. F.oxysporum was widely spread and accounted for the highest percent of 69.66, while F.solani and F.moniliforme were relatively lower 21.99 and 8.35 percent, respectively. Pathogenic testing in the laboratory showed that Fusarium oxysporum the pathogen of the disease. the disease indexwas 60.2.Evaluated the 10 onion cultivars resistance for the disease with plate method.The results showed that cultirars resistant for the disease was difference, among which Mutong and Jinmei F1 showed middle resistance for F.oxysporum, Taiyanggelin and Xiongshi middle susceptible, Ouzhoubao 1 high susceptible,and Hongsejindian,Hongpi 08, Huangpi 02, Zijin505F and Hongbao 911F1 susceptible, respectively.The inhibition effect of 4 kinds of fungicides to 3 Fusarium had difference, in whch EC50 of Carbendazim,Chlorothalnil,Emeifu and Shijunke for F.oxysporum was 69.58、158.12、143.13、6.03μg/mL, respectively. For F.solani was 5.87,152.76,35.75,70.12μg/mL,respectively. And for F.moniliforme was 49.53,2.11,4.48,126 .61μg/mL, respectively. The inhibition effect of Shijunke demonstrated the strongest place and Carbendazim took second ,while Chlorothalnil showed the weakest one. The correlation coefficient of 4 fungicides was over 0.98 . And positive correlation were found between pharmaceutical concentration and inhibition effect.Seven kinds of fungicides were used for chemical control experiment in Xincheng Town of Jayuguan City and made field plots trial. The plots were designed randomly, and duplicated 4 times. After a comprehensive evaluation of each plots of incidence rate,disease index and yield, the results showed that the best effect of 15% Avermectin.Toxin 1500X and 1000X were 84.79% and 81.11%. The onion treated with 15% Avermectin.Toxin 500 X and 1500 X demonstrated increase production,which came to 14.23% and 8.54%,while 40% Phoxim EC 800 X decreased by 6.64%. However,no significant difference of production treated with 90% Trichlorfon 0.6g/acreas or 1.2g/acreas and 40% Phoxim EC 400 X were found.更多还原