辽东栎种实害虫主要种类及为害动态和防治适期研究

Study on main species and population dynamics of fruit pests of Quercus liaotungensis

以辽东栎种实害虫为调查对象,采用林间调查和室内饲养的方法,结合统计分析,研究了黄土高原子午岭林区2019—2021年辽东栎主要种实害虫种类及其与种子生长发育、不同结实年份之间的关系。结果表明:辽东栎种实害虫主要有柞栎象、榛实象、栎实黑象、栗白小卷蛾及桃蛀螟5种;果形指数为1.2,相对含水率为42.73%,淀粉含量为47.22%时,受害率最高;结实丰年受害率最高,结实欠年虫口密度最大。6月下旬至7月上旬(幼果期)为种实害虫为害始期,7月中旬至8月中旬(生长期)为为害始盛期,8月下旬至9月中旬(成熟期)为为害盛期,防治适期应在6月下旬之前及10中旬之后;无论是结实丰年还是欠年都应加强虫害防治。

In this study,we studied the main fruit pest species of Quercus liaotungensis and their relationship with seed growth and yield in the Ziwuling forest region of the Loess Plateau from 2019 to 2021 by means of field investigation and laboratory breeding.The results showed that there were five types of fruit insect pests,including Curculio dentipes,Curculio dieckmanni,Curculio sp.,Cydia kurokoi,and Dichocrocis punctiferalis.The damage rate was the highest when the fruit shape index was 1.2,the relative water content was 42.73%,and the starch content was 47.22%.The damage rate was the highest in the year of abundant harvest,and the pest density was the highest with an insufficient yield.To sum up,from late June to early July(young fruit period)was the beginning period of seed pest damage,from mid-July to mid-August(fruit growth period)was the onset of the peak damage period,and from late August to mid-September(mature period)was the peak period of damage.The control action should be taken before late June and after mid-October.Pest management should be strengthened whether the harvest is good or not.