Abstract:

【Objective】 To clarify the genetic stability of thelytokous line of Trichogramma dendrolimi (Matsumura) infected with Wolbachia by horizontal transfer under abnormal circumstance, and adaptation between Wolbachia and its host. 【Method】 Parasitic, reproductive and several other biological characteristics of thelytokous line of Trichogramma dendrolimi were investigated in treatments of feeding with tetracycline, continuance of high temperature and mating. 【Result】 After treatment with tetracycline, male Trichogramma emerged in the F2 generation of the thelytokous line, the males induced by tetracycline mated with females induced to produce offspring, and male individuals appeared in all 20 descendant families. At normal temperature of 25℃, the mating of thelytokous line of Trichogramma dendrolimi reduced the number of parasitic compared to non-mating markedly until the F7 generation. However individual males presented incidentally in generations F2 and F4, not found in other generation with mating and all generation without mating. At relative higher temperature of 32 ℃, individual males presented in whole generation of F5 including mating and non-mating. 【Conclusion】 Stability of thelytokous line of Trichogramma dendrolimi infected with Wolbachia can not be affected by mating at 25℃ and 32℃, antibiotic treatment and higher temperature of 32℃ lasting at least 20 d are the key factors to eliminate Wolbachia to alter thelytokous of Trichogramma dendrolimi .

Key words: Wolbachia')">Wolbachia, Trichogramma dendrolimi, parthenogenesis, stability