西藏林芝七星瓢虫Coccinella septempunctata对不同蚜虫的捕食功能反应

Study on the Predation Functional Response of Coccinella septempunctata to different Aphids in Nyingchi Tibet

为了解西藏林芝天敌昆虫对害虫的捕食功能,以便保护和利用天敌,在室内初步研究七星瓢虫对月季长管蚜Macrosiphum rosirvorum、甘蓝蚜Brevicoryne brassicae和萝卜蚜Lipaphis erysimi的捕食功能。采用Holling-Ⅱ型方程对七星瓢虫捕食月季长管蚜、甘蓝蚜和萝卜蚜的作用进行拟合。结果表明:七星瓢虫对月季长管蚜、甘蓝蚜和萝卜蚜的捕食功能符合HollingⅡ型,圆盘方程分别为:Na=0.8308Nt/(1+0.0099Nt)、Na=0.9182Nt/(1+0.0026Nt)、Na=0.9412Nt/(1+0.002Nt)。随着蚜虫密度的增大,七星瓢虫的捕食量也逐渐增加,每头瓢虫对不同蚜虫的捕食上限分别为:101.01头、384.62头、500.00头。每捕食1头蚜虫所需时间Th分别为:0.009 9 h、0.002 6 h、0.002 0 h。对不同蚜虫瞬时的猎物发现率(攻击率)a′分别为:0.830 8、0.918 2、0.941 2。七星瓢虫对蚜虫的捕食作用在一定的空间范围内受其自身的密度制约,相互间存在干扰,并且对不同蚜虫的干扰系数m分别为:0.589、0.819、0.756。七星瓢虫在西藏具有较好的捕食功能。

In order to understand the predation function of the natural enemies in Nyingchi Tibet and to protect and utilize natural enemies, the predation function of C. septempunctata on M. rosirvorum, B. brassicae and L. erysimi was preliminarily studied. The Holling-II equation was used to fit the effect of C. septempunctata on the feeding of the long-term carp, cabbage bud and radish. The results showed that the predation function of C.septempunctata was consistent with Holling Ⅱ, and the disk equations were Na=0.8308Nt/(1+0.0099Nt), Na=0.9182Nt/(1+0.0026 Nt) and Na=0.9412 Nt/(1+0.002 Nt). With the increase of the density of locusts, the predation of J. serrata increased gradually. The predation limit of each ladybug to different locusts was 101.01, 384.62 and 500.00. The time required for each predation of aphids was 0.009 9 h, 0.002 6 h and 0.002 0 h. The instantaneous prey rate(attack rate) a’ for different aphids was 0.830 8, 0.918 2, and 0.941 2, respectively. The predation effect of the ladybird on the aphids was limited by their own density in a certain spatial range, and there were interferences between them, and the interference coefficients m for different aphids were 0.589, 0.819 and 0.756. In conclusion, C.septempunctata has a good predation function in Tibet.