嘉峪关市洋葱基盘腐烂病病原鉴定及药剂室内毒力测定

为了明确嘉峪关市洋葱基盘腐烂病害的病原、致病性和优势病原种群,对4个采样区洋葱基盘腐烂病采用组织分离法进行了分离,并根据其培养性状和形态学特征进行了鉴定。结果表明,该病害的病原为尖镰孢菌、茄镰孢菌和串珠镰孢菌,其中尖镰孢菌为优势种。室内致病性测试结果表明,3种镰孢菌均可引起洋葱基盘腐烂病,其中尖镰孢菌的致病性最强,发病率和病情指数最高,分别为84.4%和65.3,极显著高于(P＜0.01)其他2种菌。为筛选化学防治有效的杀菌剂,采用平皿菌丝生长抑制法在室内测定了多菌灵、百菌清、恶霉福和施菌克4种药剂对以上3种镰孢菌菌丝生长的抑制作用,结果表明,4种杀菌剂对3种镰孢菌菌丝生长均有一定的抑制作用,其中200 μg/L的施菌克抑制效果最好。

Nutrient assimilating capacity of Lolium multiflorum pasture for dairy farm biogas slurry

Four sampling points from Jiayuguan, Gansu province were investigated to determine the pathogen, pathogenicity, and dominant population of onion basal plate rot disease. Based on morphological and cultural characters the disease pathogens were identificated as Fusarium oxysporum, F. solani and F. moniliforme. The dominant species was F. oxysporum and although pathogenicity testing showed that the three species could cause onion basal plate rot disease, F. oxysporum had the strongest pathogenicity and its disease rate and disease index reached 84.4% and 65.3, respectively. Compared with the other fungi, there was a significant difference. Laboratory toxicity tests of four fungicides to the mycelial growth of the three species showed that 200 μg/L of the Shijunke fungicide had the strongest activity. 