共生菌Wolbachia感染对果蝇适合度的影响

The effects of Wolbachia infection on the fitness of Drosophila melanogaster

近年来的研究表明,Wolbachia会对多种昆虫的生殖和生长发育等产生影响,但对于果蝇的适合度影响研究较少.本研究比较黑腹果蝇Drosophila melanogaster感染和未感染Wolbachia品系在产卵量、孵化率、发育历期、成虫寿命及生命期望值方面的差异.结果显示,Wolbachia感染显著降低了果蝇的产卵量(P<0.000 1)、孵化率(P=0.018)、化蛹率(P<0.000 1)、羽化率(P<0.000 1)和成虫寿命(P<0.000 1),导致幼虫的发育历期延长(P<0.000 1),且卵期和I龄、Ⅱ龄和Ⅲ龄期幼虫生命期望值均降低.感染Wolbachia果蝇品系的相对适合度为0.688,表明Wolbachia感染对果蝇的生长发育和繁殖存在有害的影响.

Recent studies have indicated that Wolbachia can affect the reproduction, growth and development of many kinds of insects, but there are few studies of its effect on the fitness of Drosophila melanogaster. In the present study, we compared the differences in the fecundity, hatching rate, developmental duration, adult longevity and life expectancy of D. melanogaster between infected and uninfected Wolbachia. The results showed that Wolbachia infection significantly reduced the oviposition amount （P 〈 0. 000 1 ）, hatching rate （ P = 0. 018 ）, pupation rate （ P 〈 0. 000 1 ）, emergence rate （ P 〈 0. 000 1 ） and adult longevity （P 〈 0. 000 1 ） of D. melanogaster. Meanwhile, Wolbachia infection could cause the flies to prolong developmental durations （P 〈 0. 000 1 ）, and decrease life expectancy in egg, first instar, second instar and third instar larvae. Strain of D. melanogaster infected Wolbachia was calculated to have a fitness value of 0. 688 relative to the uninfected one, indicating that there is the harmful effects of Wolbachia infection on the reproduction and development of D. melanogaster.