松天牛小首螨对极端温度耐受性的驯化效应及低温存储研究

Acclimation induces tolerance to extreme temperatures and low storage temperature conditions in Paracarophenax alternatus Xu and Zhang

【目的】松天牛小首螨是近年发现的首个能够寄生致死松墨天牛卵的一个螨类新种,研究该螨对极端温度耐受性的驯化效应和低温存储条件,有助于进一步评估该螨的潜在地理分布或应用区域,并为该螨的规模化运输和存储提供基础依据。【方法】通过不同温度条件驯化后,测定松天牛小首螨暴露在极端温度下的存活率,同时比较不同低温条件下存储的松天牛小首螨膨腹体涌出的成螨数量,以及存储的雌成螨的生存情况。【结果】高温驯化可显著提高雌成螨高温暴露存活率,其中30℃36 h驯化后的存活率提高了1.26倍;低温驯化可显著提高雌成螨极端低温暴露存活率,其中10℃96 h、10℃120 h驯化后的存活率分别提高了2.08和2.13倍。以膨腹体为存储对象,低温存储后涌出成螨的数量随着存储时间延长而逐渐显著减少;以雌成螨为存储对象,在10℃条件下存储30 d,存活率为65.10%,在4℃条件下存储30 d,存活率达84.21%。【结论】松天牛小首螨具有很强的温度适应性,短期温度驯化即可大幅提升其对极端温度的耐受性。膨腹体适合作为该螨短期低温存储对象,雌成螨则适合作为中长期低温存储对象。

【Aim】Paracarophenax alternatus is the first species reported to parasitize and kill Monochamus alternatus eggs.Studies on acclimation effects in P.alternatus resulting in extreme temperature tolerance and low-temperature storage may help assess the potential geographical distribution or application area,and provide a basis for insights into large-scale transportation and storage durability of this mite.【Method】After acclimatisati on at different temperatures,survival rates of P.alternatus were recorded following exposure to extreme temperatures.The number of adult mites released from the expanding abdomen of P.alternatus and survival rates of adult female mites were compared under different low-temperature conditions.【Result】Survival rates of adult female mites exposed to high temperatures increased 1.26-fold after acclimatisati on at 30℃for 36 h.Survival rates of adult females exposed to extremely low temperatures significantly increased(2.08-fold and 2.13-fold)after acclimatisati on at 10℃for 96 h and 120 h.Low-temperature storage effects were assessed using the expanding abdomen as a storage object.The number of emerging mites gradually and significantly decreased with increasing storage time.When female adult mites were used as storage objects,the survival rates of adult females were 65.10%at 10℃for 30 d and 84.21%at 4℃for 30 d.【Conclusion】P.alternatus showed high temperature adaptability.Short-term temperature acclimatisati on can markedly increase its tolerance to extreme temperatures.The expanding abdomen is suitable for short-term storage,and adult females are suitable for medium-and long-term storage.