建兰胶孢炭疽菌分生孢子的生物学特性及病害防治药剂的筛选

Biological characteristics of the conidia of Colletotrichum gloeosporioides infected with Cymbidium ensifolium and the selection of fungicides against the disease

研究了室内温度、pH值和光照对建兰胶孢炭疽菌(Colletotrichum gloeosporioides)产孢量和孢子萌发的影响,测定了孢子的致死温度及时间,用田间药效试验法筛选建兰炭疽病的防治药剂.结果表明,该菌产孢和孢子萌发的适宜温度为25-28℃,pH值为中性或偏微酸,光照条件为完全黑暗或12 h光暗交替,55℃水浴中5 min孢子致死.田间药效试验结果表明,4种供试药剂对建兰炭疽病的防治效果均在60%以上,以78%波尔.锰锌可湿性粉剂和10%苯醚甲环唑水分散粒剂的速效性和持续性最好.

The influences of temperature, pH value and light to the sporulation and conidia germination of Colletotrichum gloeospori- oides were studied, and the lethal temperature and time of the spores were determined indoors, the control agents aginst Cymbidium anthrax were screened by field efficacy trials. The result showed that for this fungi, the optimal conditions of the sporulation and conidia germination were as follows： temperature was 25 -28 ~C, pH value was neutral （slight acidity）, light condition was com- plete darkness or alternation of light and darkness every 12 hours, the lethal temperature was 55 ~C in the water for 5 rain. The field efficacy trial result showed that the control efficiency on Cymbidium anthrax of all the tested pesticides were more than 60%, the quick-acting and persistence of 78% Bordeaux mixture plus Mancozeb WP and 10% Difenoconazole WDG were the best.