关键词: 落叶松尺蠖, 气候变化, 繁殖力, 存活率, 有效积温, 雄性先熟

Abstract: Erannis ankeraria is one of the most important pests in larch. In order to investigate the effects of temperature on E. ankeraria, larch (Larix principisrupprechtii) branches were inserted into water in the bottles to keep fresh and used as the host plant to rear the larvae. Seven constant temperatures (15, 19, 23, 25, 27, 29 and 31 ℃) were set up to test the effects of temperature on the developmental duration and survival of eggs, larvae and pupae of E. ankeraria. The results showed that temperature significantly affected developmental duration, survival rate, pupa weight, fecundity, and oviposition rhythm of E. ankeraria. E. ankerariacould complete the individual development cycle from egg to adult only within the range of 15-19 ℃.Adults could not emerge when the temperature was above 23 ℃. The pupation rate decreased as the temperature was above 25 ℃. The hatching rate and larval survival rate decreased at 29 ℃. The developmental threshold temperature of over-wintering eggs and larvae of E. ankerariawas 9.7 and 4.3 ℃, respectively. The effective accumulated temperature was 104.2 and 459.8 day-degree, respectively. E. ankeraria preferred to grow and develop at low temperature. High temperature inhibited its growth and development. Higher temperature reduced the pupation rate and emergence rate. Pupal stage was the most sensitive stage to increasing temperature. Increased temperature led to earlier emergence of male moth than female moth, which reduced the chance of male and female moth encountering, thus affecting the reproduction. It is inferred that E. ankerariawill move northward in order to survive under global warming scenario, and that their damage to larch in warm areas will be reduced.

Key words: Erannis ankeraria, climate change, fecundity, survival rate, effective accumulated temperature, protandry.