北方桃园秋季桃蚜发生规律与防控药剂筛选

秋季回迁到桃园的越冬桃蚜是翌年早春危害桃树的主要虫源。为明确秋季北方桃园中桃蚜的回迁发生动态和产卵情况，以及筛选高效防治的药剂,本研究分别在北京、石家庄、泰安、兰州各选1个桃园，采用黄板诱虫，监测秋季桃园内桃蚜的成虫种群和产卵动态；通过田间药效试验，评价藜芦碱、苦参碱和矿物油等3种药剂对秋季桃蚜的田间防治效果。2017年和2018年连续两年的调查结果显示，北方桃园中桃蚜9月初开始回迁，在10月中旬有性雌蚜开始产卵越冬，10月下旬桃蚜数量明显减少。藜芦碱、苦参碱和矿物油处理防治秋季蚜虫，虽然药效较慢，但用药后14 d后防效分别在91.6%、80.6%和66.4%。北方桃园回迁的桃蚜会快速繁殖扩增种群，且秋末产卵量较多，可以在9月中下旬选择喷施藜芦碱控制桃园桃蚜，降低桃蚜种群数量，减轻翌年蚜虫防治的压力。

Occurrence regularity and screening agents of Myzus persicae in northern peach orchard in autumn

Myzus persicae, the overwintering species which moved back to the peach orchard in autumn, was the main pest source in the early spring. The objective of this study was to clarify the occurrence regularity and oviposition of M. persicae in Chinese northern orchards in autumn, and to screen the agents with the high control efficiency. The adult population and oviposition dynamics were monitored by using yellow sticky trap and observing the branches, otherwise, three pesticides were evaluated in peach orchards in Beijing, Shijiazhuang, Tai''an and Lanzhou in autumn. For the two consecutive years 2017 and 2018, M. persicae start to migrate back the peach orchards in the early September, and the number decreased in late October. In addition, the oviposition was started in the mid October, then aphids overwinter with eggs. Veratrine, matrine and mineral oil treatments had a slow effect on the control of aphids in autumn, but the control effects were 91.6%, 80.6% and 66.4% after 14 days of treatment, respectively. The relocated M. persicae rapidly propagated and expanded the population, and laid more eggs in late autumn. In the middle and late September, vertrine can be selected to control peach aphids in peach orchards, reduce the population of peach aphids, and reduce the pressure of aphid control in the next year.