昆明地区梨锈病的发生和防治

 本文报道了梨锈病在昆明地区的转主寄主树为圆柏和龙柏,及其上面冬孢子角的发生和成熟时间,以及空中冬孢子的监测。表明冬孢子分期分批成熟,为2月初和3月中旬两个高峰期,此时正是梨嫩叶感病盛期。通过各种药剂抑制冬孢子萌发和果园防治试验,筛选出预防和防治两组有效药剂。前者有石硫合剂、波尔多液、粉锈灵、代森铵、多菌灵等,预防效果达55.05%～100%;后者有粉锈灵、多菌灵、代森铵、甲霜灵等,防治效果达48.44%～100%。梨树品种的抗病性测定表明,大理水扁梨和贵妃梨对梨锈病具有较强抗性。

Studies on the Development of Pear Rust and its Chemical Control in Kunming

The pear rust caused by Gymnosporangium hareanum Syd is an alternate parasite, and its teliosporangium is formed on the Junipers (Sabina Chinensis Var. Kaizusa and Sabina Chinensis), from January to February. The infection takes place during the opening stage of leaf buds in damp or rainy days from the last ten days of February to March which coincides with the period of the dissemination of teliospores or sporidia. Some chemicals including Calcium polysulfide, Bordeaux mixture, Piperalim, Ambam and Baviston etc. can be used to kill the developing spores on the junipers and to protect the foliage of pears against rust infection. The tests showed that the Dali shui bian pear, Gui Fei pear, Huang pear, Bao zhu pear, Jia Huang pear, Lu Yi Si pear, all are disease-resistant breeds of pear.