四川省猕猴桃贮藏期炭疽病生物学特性及防治研究

Biological Characteristics and Control of Kiwifruit Anthracnose during Storage Period in Sichuan Province

通过明确四川省猕猴桃主要产区果实采后炭疽病致病的主要原因及条件,筛选高效低毒的防治药剂,为病害的防治提供有效的措施和技术指导。选取不同温度、光照、湿度、pH、碳源、氮源等条件确定炭疽病病原菌的生物学特性。分别选取50%多菌灵、65%代森锌、50%乙烯菌核利、70%甲基托布津可湿性粉剂的500倍液、800倍液、1000倍液,采用菌丝生长速率法测定4种药剂不同浓度对病原菌菌丝生长的影响。结果表明,猕猴桃炭疽病最适宜菌丝生长温度为25℃,最适宜菌丝生长湿度为30%和70%,最适pH6时菌落直径最大,菌丝生长相对最快,病原菌对光照条件不敏感,猕猴桃炭疽病菌在以麦芽糖为碳源时生长最快,以乳糖为碳源时生长最慢;以蛋白胨为氮源时生长最快,在硫酸铵上生长最慢,且菌落畸形。高效低毒试验表明50%多菌灵、65%代森锌、50%乙烯菌核利、70%甲基托布津可湿性粉剂4种杀菌剂对炭疽病原菌菌丝生长的中间致死浓度差异显著,代森锌的抑制作用最强,抑制炭疽病菌分生孢子效果最好的是65%代森锌1000倍液,EC50为2.9ug/mL。

Pathogenic bacteria biological characteristics were studied to determine the main causes and conditions of the disease causing kiwifruit anthracnose in Sichuan Province,at the same time determine a high effective and low poisonous reagents to grasp integrated control.It can provide effective measures and technical guidance for disease prevention and control. The biological characteristics of anthrax pathogenic bacteria were determined by selecting different temperature,illumination,humidity,pH,carbon source and nitrogen source.The mycelium growth rate method was used to determine the influence of four different agents which have different concentrations on the mycelium growth.A total of 500 times,800 times and 1 000 times of 50% carbendazim,65% zineb,50% vinclozolin and 70% thiophanate-methyl wettable powder were selected respectively.The biological characteristics showed that Colletorichum acutatum mycelial growth optimum temperature was 25 ℃,the optimum humidity was 30%RH and 70% RH,the optimum pH was 6 respectively,and had no remarkable effect of light on mycelium growth of pathogens.The optimum carbon source was maltose and when lactose was the carbon source,the growth was the slowest. The optimum nitrogen source was peptone and when ammonium sulfate was the nitrogen source,the growth was the slowest which had malformationcolony of bacteria. The high effective and low poisonous experiment showed that 50% carbendazim,65% zineb,50% vinclozolin and 70% thiophanate-methyl wettable powder all had significant differences with median lethal concentration in anthracnose pathogenic bacteria growth and zineb inhibitory effect was the strongest.The strongest inhibitory effect on Colletorichum acutatum conidium was 65% zineb 1 000 times liquid,EC 50 2.9 ug/mL.