Objective  This study mainly focused on the continuous mating ability, the effects of adult stage and mating experience on reproductive ability, and the effects of mating behavior on the lifespan in Bursaphelenchus xylophilus. Our data showed the difference in reproductive strategies between male and female nematodes and clarified their mating characteristics, providing a novel idea of interfering mating behavior to control the population growth of B. xylophilus.

  Method  The synchronous virgin male and virgin female of B. xylophilus were obtained. The continuous mating ability of pine wood nematode was analyzed through continuous tracking observation and microscopic video playback. B. xylophilus was collected on day 3, 5 and 7 after sexual maturity and at different mating experience. Their mating success rate and average egg production were counted separately for analyzing the effects of adult stage and mating experience on the reproductive ability. And the lifespan of virgin male and female and mated male and female nematodes were quantified.

  Result  In B. xylophilus, a virgin male could successfully mate with three virgin females in a row without feeding, and made them conceive and lay eggs. However, after successfully mating, virgin females laid eggs first and did not mate continuously. For virgin male and female nematodes, both the mating success rate and average egg production decreased with the increase of adult stage. This reached significant levels of difference at day 7 and day 5 after sexual maturity, respectively. Females were more significantly affected by adult stage than males. There were significant differences in the mating success rate of males and females of B. xylophilus with different mating experience. For virgin males and females on day 3 after sexual maturity, they were (60.00 ± 9.43)% and 100%, respectively. For mated males and females of the same adult stage, they were significantly reduced to (17.50 ± 4.68)% and (25.00 ± 2.34)%, respectively. However, there was no significant difference in their average egg production. In addition, the mating behavior had no significant impact on the lifespan of pine wood nematode. For virgin and mated females, the average lifespan was (24.47 ± 0.22) d and (24.93 ± 0.70) d, respectively. Whereas, for virgin and mated males, it was (21.80 ± 0.54) d and (23.43 ± 0.78) d, respectively.

  Conclusion  In B. xylophilus, virgin males could mate multiple times in succession, while virgin females lay eggs first after mating. Moreover, both adult stage and mating experience significantly affect their mating success rate, but average egg production is only affected by adult stage. However, mating behavior does not accelerate their senescence. This study clarified the mating characteristics of B. xylophilus and laid a theoretical foundation for exploring its molecular regulation mechanism.