商洛核桃产区举肢蛾虫害调查与防治试验

举肢蛾是为害核桃果实的主要害虫。调查结果表明,商洛核桃产区举肢蛾发生率平均为37.6%,为害程度与海拔、地理位置和立地条件等密切相关。表现为低海拔(800 m)地区重于高海拔(1 200 m)地区;阴坡重于阳坡;沟道重于平川;荒坡地重于耕地;阴湿多雨年份重于干旱年份。在防治时应遵循"加强预测预报、物理与化学防治相结合,长期、综合防治"的原则。化学防治从举肢蛾羽化率达到10%~15%(麦梢发黄即将收割时)开始采取措施,喷洒0.5%的二甲基二硫醚1 000倍液1 500 kg/hm2,连续喷3次,每次间隔10 d,可将虫害率控制在9.2%以下,防治效果较好。

Investigation and Control of Atrijuglans hetaohei in Walnut Production Area of Shangluo

Atrijuglans hetaohei was the main pest damaged walnut fruit.The damage was investigated in walnut production area of Shangluo.The results showed that the average occurrence rate of A.hetaohei was 37.6%,which was closely related to the altitude,geographic location and site conditions,etc.The damage was more serious in the areas with an altitude of lower than 800 m,in shady slope and in barren land than that in the areas with an altitude of more than 1 200 m,in sunny slope,and in cultivated land,which was more serious in rainy year than in dry year.The principle of strengthening forecast,combining physical control with chemical control,and taking long-term,comprehensive prevention in the control should be followed.Chemical control should be taken when the emergence rate reached 10%-15%.The rate of damage could be controlled below 9.2% by spraying 1 000 times liquid of 0.5% dimethyl disulfide 1 500 kg/hm2 3 times every 10 days.