Key Lab of Integrated Crop Pest Management of Shandong Province, College of Agronomy and Plant Protection, Qingdao Agricultural University, Qingdao, China.
PLoS One. 2014 Jun 19;9(6):e100423. doi: 10.1371/journal.pone.0100423. eCollection 2014.
Our long-term field survey revealed that the Cardinium infection rate in Bemisia tabaci Q (also known as biotype Q) population was low in Shandong, China over the past few years. We hypothesize that (1) the Cardinium-infected (C+) B. tabaci Q population cannot efficiently compete with the Cardinium-uninfected (C-) B. tabaci Q population; (2) no reproductive isolation may have occurred between C+ and C-; and (3) the C- population has higher fitness than the C+ population.
To reveal the differences in competitive ability and fitness between the two introduced populations (C+ and C-), competition between C+ and C- was examined over several generations. Subsequently, the reproductive isolation between C+ and C- was studied by crossing C+ with C- individuals, and the fitnesses of C+ and C- populations were compared using a two-sex life table method. Our results demonstrate that the competitive ability of the C+ whiteflies was weaker than that of C-. There is that no reproductive isolation occurred between the two populations and the C- population had higher fitness than the C+ population.
The competitive ability and fitness differences of two populations may explain why C- whitefly populations have been dominant during the past few years in Shandong, China. However, the potential role Cardinium plays in whitefly should be further explored.
我们的长期田间调查显示，过去几年中国山东烟粉虱 Q 型（又称 Q 生物型）种群中的卡他霉素感染率较低。我们假设：（1）感染卡他霉素的（C+）烟粉虱 Q 型种群不能有效地与未感染卡他霉素的（C-）烟粉虱 Q 型种群竞争；（2）C+和 C-之间可能没有发生生殖隔离；（3）C-种群比 C+种群具有更高的适合度。
为了揭示这两个引入种群（C+和 C-）之间竞争能力和适合度的差异，我们对 C+和 C-之间的竞争进行了几代的研究。随后，通过将 C+与 C-个体杂交，研究了 C+和 C-之间的生殖隔离，并使用两性生命表法比较了 C+和 C-种群的适合度。我们的研究结果表明，C+粉虱的竞争能力弱于 C-粉虱。这两个种群之间没有发生生殖隔离，C-种群的适合度高于 C+种群。
两个种群之间竞争能力和适合度的差异可能解释了为什么在过去几年中，C-烟粉虱种群在中国山东一直占主导地位。然而，卡他霉素在粉虱中的潜在作用还需要进一步探索。
