加州新小绥螨在不同温度下对六点始叶螨的捕食效能

Function response of Neoseiuius californicus feeding on Eotetranychus sexmaculatus at different temperatures

为明确加州新小绥螨对橡胶六点始叶螨的控害潜能,系统研究了21℃、24℃、27℃、30℃、33℃5个不同温度条件下加州新小绥螨对六点始叶螨各螨态的捕食效能和自身密度干扰效应。结果表明:加州新小绥螨对六点始叶螨若螨、幼螨和卵的选择系数分别为0.71、1.75和0.54。在21℃~33℃条件下,加州新小绥螨对不同螨态六点始叶螨的功能反应均能很好地拟合Holling-II型圆盘方程,其对六点始叶螨雌成螨、若螨、幼螨的捕食效能(a/Th)在30℃时最强,分别达19.91、44.90、189.45头/d,对叶螨卵的捕食能力在不同温度间差异不显著。在同一温度条件下,加州新小绥螨对不同螨态六点始叶螨的捕食量大小依次为:幼螨>若螨>成螨>卵。在相同的猎物密度条件下,加州新小绥螨的捕食作用率随其自身密度的增加而逐渐降低,说明加州新小绥螨存在种内竞争和自我干扰作用,自身干扰系数为0.349。

To figure out the control potential of Neoseiulus californicus on Eotetranychus sexmaculatus , the functional response and interference effect of N.californicus to E.sexmaculatus were studied at five different temperatures, i.e. 21℃, 24℃, 27℃, 30℃ and 33℃. The results showed that the selective coefficient of N.californicus for the nymphs, larva and egg of E.sexmaculatus was 0.71, 1.75 and 0.54, respectively. The functional response of N.californicus to E.sexmaculatus at different temperatures all matched Holling-II disc equation. At 21℃~33℃, the predation capability ( a/Th ) of N.californicus to the female adult, nymphs and larva of E. sexmaculatus was the strongest at 30℃ and the a/Th value was 19.91, 44.90, and 189.45, respectively. However, the predation ability of N. californicus on the egg of E.sexmaculatus had no obvious difference at different temperatures. The predation number of N.californicus feeding on E.sexmaculatus (at different stages) under the same temperature was ranked as larva> nymph>adult> egg. When prey density was the same, the predation ration of N.californicus would gradually decrease with the increase in the density of N.californicus . This proved that strong competition and self-interference indeed existed among N.californicus , and the self-interference coefficient was 0.349.