弟兄鳃金龟生物学特性观察

Studies on the Bionomics of Melolontha Frater Arrow

弟兄鳃金龟是山西省北部地区为害大秋作物的重要地下害虫之一。4年完成一代,以幼虫越冬。翌年4月中旬,幼虫开始上升,5月下旬至6月上旬,全部到达耕作层中活动为害。幼虫历经46个月后,于第4年6月中下旬老熟,在距地表18～39.5cm的土层中做土室化蛹,蛹期约40天。6月下旬至7月上旬羽化为成虫。成虫傍晚活动,交尾产卵,但不取食。

Melolontha frater Arrow is one of the main underground pests in North Shanxi. It was indicated that one generation of the insect is reproduced every four years. The first, second or third instar larvae began to move into deeper soil layer during 10th to 20th October. They overwintered in the soil at 180cm depth. The pest started to active in April. From 20th May to 10th June all the insects moved to the cultivate layer at 20cm depth and began to damage the crops. The duration of larvae lasted about 46 monthes. Then the old third instar larvae made rooms and pupated in the soil at 18 to 39.5 cm depth. The pupal period was about 40 days. From 20th June to 10th July they emerged to adults and began to mate and oviposit in the evening without taking food.