核桃枝枯病病原菌生物学特性及药剂防治

Biological Characteristics of Walnut Branch Rot Pathogen and Its Chemical Prevention

对核桃枝枯病的新病菌新壳梭孢（Neofusicoccum parvum）研究发现,菌落生长初期颜色为白色,逐渐成灰黑色,培养3周后变成黑色。最佳培养条件为：PDA培养基、温度25~30℃、p H=7~8、全光照、100%湿度、碳源为葡萄糖,氮源为谷氨酸。选取9种化学药剂对病菌进行了室内药剂的筛选,通过菌丝生长抑制试验,筛选出70%甲基托布津可湿性粉剂、50%多菌灵可湿性粉剂和75%百菌清可湿性粉剂3种高效药剂,其抑制率依次为66.67%、64.44%、44.44%。

We studied the walnut branch rot,a new pathogen called Neofusicoccum parvum,and found that the initial growth color of colony was white,ash black gradually,then black after it was cultured after three weeks.The optimum culture conditions for walnut branch pathogen were under the PDA medium,25 ℃-30 ℃,full illumination,100% of humidity,the carbon source of glucose,and a nitrogen source.We selected nine kinds of chemicals which were screened for bacteria pharmacy test chamber,then three kinds of effective pharmacy screened by using the mycelial growth inhibition test.The best control effect successively were 70% thiophanate-methyl wettable powder,50% carbendazim WP and 75% chlorothalonil WP with inhibition ratios of 66.67%,64.44% and 44.44%,respectively.