剑麻提取液对芒果炭疽病菌的抑制作用及苗期防治效果

本文利用剑麻提取液对芒果炭疽病的防治进行了研究，结果表明，剑麻叶片水提液对芒果炭疽病菌的菌丝扩展速度以及菌丝生长量均有明显的抑制作用，且随着处理浓度的增高，抑制效果增强，当每100mL培养基中加0．2mL提取液处理时，抑制率达到50％以上；对孢子产孢能力以及孢子萌发率也有明显抑制作用，当100mL培养基中加5mL提取液处理时，产孢抑制率为98．18％，孢子萌发抑制率为97．43％；用提取液处理菌丝后电导率升高，表明该提取物对芒果炭疽病菌菌丝体细胞结构有影响，导致菌丝体电解质外渗；芒果苗期盆栽试验表明，处理后21d，对照发病率达到92．22％以上，而处理仅为44．44％，表明该提取物对芒果炭疽病有明显的防治效果。

Inhibition of Agave sisalana Leaf Extracts on Colletotrichum gloeosporioides Penz. and Their Control Effect at the Seedling Stage

The control effect of Agave sisalana Perrine leaf extract on mango anthracnose Colletotrichum gloeosporioides Penz. was studied in this paper. The results showed that growth rate and quantity of mycelia were suppressed obviously by the extracts. When 0.2 mL extracts were added to 100 mL culture media, the mycelia growth rate was 50%. When 5 mL extracts were added to 100 mL PDA, the restraining rates of proliferation and germination were 98.18% and 97.43% respectively. When the mycelium was treated directly by the extracts, the electric conductivity of handling liquid was increased, which meant the cell structure of mycelia was break down and electrolyte leakage. The mango plants were treated by the extracts at the 21 d, the seedling disease incidence of control plants was more than 92.22%, but the treated plants＇ was just 44.44%. So the extracts of A. americana could control C. gloeosporioides effectively.