宁夏果树产区梨小食心虫的发生规律

为了明确梨小食心虫(Grapholitha molesta Busck)在宁夏果树栽培区的发生规律和危害特征。选苹果、梨、杏、梅等品种,分别放置梨小食心虫诱芯,在生长季节逐日对各诱集点诱芯诱集成虫数量,以及田间危害损失、发生代数、发育历期进行调查。经3a定点系统研究,结果表明,梨小食心虫每年可发生4代,即4月中旬越冬代开始,5月中旬第1代,6月中旬第2代,7月中旬到8月初第3代,8月下旬到9月上旬以老龄幼虫越冬。生长季节对不同果树品种危害呈以下时间特征:为害先从杏开始,接着梅子,然后早熟梨,最后苹果。采用梨小食心虫性诱芯预报成虫高峰期,结合果树的开花和结果物候期可确定发生期的防治关键期。

Studies on Occurrence Law of Grapholitha molesta in Ningxia

In order to reveal the occurrence law and damage characteristics of G.molesta in Ningxia, the daily adult population was trapped by the bait of G.molesta, to investigate generations and developmental duration of G.molesta and fruit loss during the growing season of apple, pear, apricot and plum. The result indicated that G.molesta has 4 generations per year, i.e. overwinter generation in mid-April, first generation in mid-May, second generation in mid-June, third generation in mid-July or early August, and the mature larvae overwintering in late August or early September. The occurrence of G.molesta related to phonological period of fruit tree, and the species infested firstly apricots and plums, then damaged early ripening pear and apples. The key period of controlling G.molesta can be speculated through the combination of pheromone trapping and phonological period of fruit tree.