中文摘要：

【目的】研究松材线虫不同环境条件下繁殖策略,为该病种群扩张繁殖生物学的深入研究和防控策略的制定提供理论基础。【方法】通过显微观察检测在营养和蒎烯胁迫条件下松材线虫雌雄比变化规律。【结果】在营养富足条件下,松材线虫雌虫比例增加,反之松材线虫雄虫比例增高;低浓度α-蒎烯和β-蒎烯胁迫条件下,松材线虫雌雄比降低,而高浓度α-蒎烯处理后,松材线虫雌雄比升高,雌性后代比例增大;在低浓度α-蒎烯和低浓度β-蒎烯混合处理条件下,松材线虫雌雄比最低,且一直稳定在较低水平。【结论】松材线虫在适宜环境条件下有利于雌性后代的发育,而不适宜环境条件下雄性后代发育更快,因此,松材线虫可能通过种群雌雄比来调整其种群繁殖力,从而适应不同环境的变化。

英文摘要：

【Objective】 The sex ratio is one of the determining factors of the nematode reproduction rate that is key for the pathogenicity,and population expansion of pine wood nematode,Bursaphelenchus xylophilus.This study aims to survey the reproductive tactics of PWN under different cultural conditions for providing a theoretical basis for futher study on the population expansion relatived to reproductive behavior and strategy for prevention and control of pine wood disease.【Method】 We investigated the change pattern of PWN female to male ratio under different nutritional conditions and pinene stress by micro-examination.【Result】 The sex ratios were biased to females at nutrition-rich conditions and the nematodes exercised a masculinizing effect on the developing larvae in poor nutrition environments.The α-pinene and β-pinene were ableto inhibit the nematode＇s reproductive rate with low sex ratio at low concentration but promote the rate at high concentration with high sex ratio.The β-pinene might inhibit the reproduction potential with low sex ratio at low and high concentration.The sex ratio was lowest and relatively stable under the mixture stress of low concentration α-pinene and β-pinene.【Conclusion】 The PWN sex ratios were biased to females at favorable environmental conditions and the nematodes exercised a masculinizing effect on the developing larvae in uncomfortable environments.Thus we infer that the PWN would control the reproduction rate by modifying the sex ratio to adapt the environment change.