摘要: 目的本文通过测定松材线虫连续交配能力，分析虫龄和交配经验对松材线虫繁殖能力的影响，并研究松材线虫寿命对交配行为的响应，比较松材线虫雌雄虫生殖策略的差异性，明确松材线虫的交配特性，为从交配干扰角度找到控制松材线虫种群增长的切入点提供新的思路、�/sec> 方法获得同步发育的松材线虫处女雌虫和处子雄虫，通过连续跟踪观察，结合显微录像视频回放，分析松材线虫的连续交配能力。分别收集性成熟后�?天、第5天和�?天的松材线虫，以及不同交配经验的松材线虫，统计其交配成功率和产卵量，分析虫龄和交配经验对松材线虫繁殖能力的影响。同时，定量分析未交配和已交配松材线虫雌雄虫的寿命、�/sec> 结果处子雄虫在不取食的情况下，可以连续与3条处女雌虫成功交配并使其受孕产卵；而处女雌虫成功交配后先进行产卵，不会连续交配。对于未交配雌雄虫而言，交配成功率和平均产卵量均随着虫龄的增加而降低，交配成功率于性成熟后�?天达到差异显著水平，而平均产卵量于性成熟后�?天达到差异显著水平，且雌虫受虫龄的影响较雄虫更为显著。不同交配经验的松材线虫雌雄虫交配成功率存在显著差异，性成熟后�?天未交配雌雄虫的交配成功率分别为�?0.00% ± 9.43%）和100%，而相同虫龄已交配雌雄虫的交配成功率分别降至（17.50% ± 4.68%）和�?5.00% ± 2.34%），但其平均产卵量无显著差异。交配行为对松材线虫的寿命没有显著影响，未交配和已交配雌虫的平均寿命分别为（24.47 ± 0.22� d和（24.93 ± 0.70� d，未交配和已交配雄虫的平均寿命分别为�?1.80 ± 0.54� d和（23.43 ± 0.78� d、�/sec> 结论松材线虫处子雄虫可以连续进行多次交配，而处女雌虫交配后会优先产卵。虫龄和交配经验均会显著影响松材线虫的交配成功率，但产卵量仅受虫龄影响。此外，交配行为不会加速松材线虫衰老。本研究明确了松材线虫的交配特性，为进一步探究其分子调控机制提供了理论基础、�/sec>

关键诌�
• 松材线虫/
• 交配特�?/a> /
• 虫龄/
• 交配经验/
• 繁殖能力/
• 寿命

Abstract: ObjectiveThis study mainly focuses on continuous mating ability, the effects of adult stage and mating experience on reproductive ability, and the effect 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. MethodThe synchronous virgin male and virgin female of B. xylophiluswere obtained. The continuous mating ability of pine wood nematode was analyzed through continuous tracking observation and microscopic video playback. B. xylophiluswere collected on days 3, 5 and 7 after sexual maturity and at different mating experience. Their mating success rate and average egg production were counted separately for analysis of 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 was quantified. ResultIn B. xylophilus, a virgin male could successfully mate with three virgin females in a row without feeding, and made them conceive and laid 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 reaching significant levels of difference at day 7 and day 5 after sexual maturity, respectively. Females were more significantly affected by adult stage than males were. There were significant differences in the mating success rate of males and females of B. xylophiluswith 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) days and (24.93 ± 0.70) days, respectively. Whereas for virgin and mated males, it was (21.80 ± 0.54) days and (23.43 ± 0.78) days, respectively. ConclusionIn B. xylophilus, virgin males could mate multiple times in succession, while virgin females laid eggs first after mating. Moreover, both adult stage and mating experience significantly affected their mating success rate, but average egg production is only affected by adult stage. However, mating behavior did not accelerate their senescence. This study clarified the mating characteristics of B. xylophilusand laid a theoretical foundation for exploring its molecular regulation mechanism.

Key words:
• Bursaphelenchus xylophilus/
• mating characteristics/
• adult stage/
• mating experience/
• reproductive ability/
• lifespan

�?nbsp; 1虫龄对松材线虫处女雌虫与处子雄虫繁殖能力的影哌�/p>

相同小写字母表示不同组别无显著差异，不同小写字母表示不同组别的差异显著性（P< 0.05）。误差棒代表平均值的标准误差。下同� Same lowercase letters indicate no significant difference between different groups, and different lowercase letters indicate significant differences between different groups (P< 0.05). Error bars represent standard error of mean. The same as below.

Figure 1.The effect of adult stage on the reproductive ability of virgin males and females ofB. xylophilus

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�?nbsp; 2交配经验对松材线虫雌雄虫繁殖能力的影哌�/p>

Control，组内为处女雌虫和处子雄虫；Treated，组内有已交配雌虫或已交配雄虫。一个星号表示两组之间差异显著（P< 0.05），两个星号表示两组之间差异极显著（P< 0.01），ns表示两组之间无显著差异（P> 0.05）。下同� Control, virgin males and virgin females in the group; treated, mated males or mated females in the group. One asterisk indicates a significant difference between the two groups (P< 0.05) and two asterisks indicate a highly significant difference between the two groups (P< 0.01), and ns indicates no significant difference between the two groups (P> 0.05). The same as below.

Figure 2.The effect of mating experience on the reproductive ability of males and females ofB. xylophilus

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�?nbsp; 3交配对松材线虫雌雄虫寿命的影哌�/p>

Figure 3.The effect of mating behavior on lifespan of males and females ofB. xylophilus

下载: 全尺寸图牆�/a> 幻灯牆�/a>

�?nbsp; 1不同虫龄的处女雌虫与处子雄虫配对实验

Table 1.Mating systems of virgin males and females at different adult stages ofB. xylophilus

不同体系 Different systems	交配组合 Mating combinations
适龄处女雌虫 × 适龄处子雄虫 Young virgin female × young virgin male	V.F4 × V.M4
适龄处女雌虫 × 大龄处子雄虫 Young virgin female × old virgin male	V.F4 × V.M7
	V.F4 × V.M9
	V.F4 × V.M11
大龄处女雌虫 × 适龄处子雄虫 Old virgin female × young virgin male	V.F7 × V.M4
	V.F9 × V.M4
	V.F11 × V.M4
大龄处女雌虫 × 大龄处子雄虫 Old virgin female × old virgin male	V.F7 × V.M7
	V.F9 × V.M9
	V.F11 × V.M11
注：V.F代表处女雌虫，V.M代表处子雄虫。V.F4、V.F7、V.F9和V.F11分别代表4�?�?�?1 d的处女雌虫；V.M4、V.M7、V.M9和V.M11分别代表4�?�?�?1 d的处子雄虫。下同。Notes: V.F represents virgin female, V.M represents virgin male. V.F4, V.F7, V.F9 and V.F11 represent virgin females of 4 days, 7 days, 9 days and 11 days, respectively; V.M4, V.M7, V.M9 and V.M11 represent virgin males of 4 days, 7 days, 9 days and 11 days, respectively. The same as below.

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�?nbsp; 2不同交配经验的雌雄虫配对实验体系

Table 2.Mating systems of males and females with different mating experience ofB. xylophilus

不同体系 Different systems		交配组合 Mating combinations
雌虫选择体系 Female selection system	适龄处女雌虫 × 大龄处子雄虫 Young virgin female × old virgin male	V.F4 × V.M7
	适龄处女雌虫 × 已交配雄� Young virgin female × mated male	V.F4 × M.M7
雄虫选择体系 Male selection system	大龄处女雌虫 × 适龄处子雄虫 Old virgin female × young virgin male	V.F7 × V.M4
	已交配雌� × 适龄处子雄虫 Mated female × young virgin male	M.F7 × V.M4
注：M.F代表已交配雌虫，M.M代表已交配雄虫。M.F7和M.M7分别代表7 d的已交配雌虫和已交配雄虫。下同。Notes: M.F represents mated female, M.M represents mated male. M.F7 and M.M7 represent 7 days mated females and mated males, respectively. The same as below.

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