草地螟交配行为及能力

Mating behavior and capacity of the beet webworm, Loxostege sticticalis

草地螟Loxostege sticticalis L.(鳞翅目:螟蛾科)是我国北方地区的重大农牧业害虫。但国内外对草地螟的交配行为和能力尚无报道。为了阐明草地螟的大发生机理及改善其监控技术水平,本文在(22±1)℃、相对湿度70±5%、光周期为L∶D=16∶8的条件下研究和揭示了草地螟的交配行为和能力。首次获得的结果表明:成虫交配从4日龄开始,9日龄达到高峰。每日的交配主要发生在晚上熄灯后4～8h(02∶00～06∶00)。雌雄成虫都能进行多次交配,交配次数1～6次不等,平均为2.4次。其中以交配2次的比例最高(32.4%),交配1次的次之(29.4%),之后的比例便随交配次数的增加而下降。草地螟的交配持续时间从21～148min不等(n=145),平均为58.7min,其中以50～70min为最多(42.1%),30～50min的次之(36.6%),小于30min的比例(2.8%)最少。另外,成虫交配持续时间随蛾龄的增加而延长(Y=1.3488x+45.429;r=0.22,P=0.008,n=145)。

The beet webworm,Loxostege sticticalis L.（Lepidoptera： Pyralidae） is an important migratory insect pest of crop and fodder plants in northern China.To better understand its outbreak mechanism,and improve monitoring and management of this pest,the mating behavior of adult L.sticticalis was studied under laboratory conditions （（22±1）℃,RH 70±5%,L∶D=16∶8）.The results indicate that mating activity begins on day-4 and peaks on day-9.Mating activity occurred between 4 and 8 hours after lights were turned off.Adults could mate from 1 to 6 times,with an average of 2.4 times during their life span.32.4% moths mated twice and 29.4% mated once with progressively lesser proportions mating more frequently.Mating duration lasted from 21 to 148 min （n=145）,with an average of 58.7 min.Most copulations lasted from 50 to 70 min （42.1%,n=145）,followed by 30 to 50 min （36.6%）,with a small proportion （2.8%） lasting less than 30 min.The duration of copulation increased with age （Y = 1.3488x ＋ 45.429;r = 0.22,P = 0.008,n = 145）.