Biological control effect of thelytokous strain Trichogramma dendrolimi
Author of the article:CONG Bin** ZHANG Tong-Shu** HU Zhi-Feng LEI Cheng-Ping ZHANG Ming-Zhu YANG Zhe ZHANG Zhu-Ting BAI Hong-Yan DONG Hui QIAN Hai-Tao***
Author's Workplace：College of Plant Protection, Shenyang Agricultural University, Shenyang 110866, China
Key Words：Wolbachia, Trichogramma dendrolimi, parthenogenesis, biocontrol
Abstract： [Objectives] To clarify the effectiveness of the thelytokous Wolbachia-infected Trichogramma dendrolimi strain as a biological control for the Asian corn borer, Ostrinia furnacalis. [Methods] A thelytokous Wolbachia-infected, and an arrhenotokous uninfected, strain of T. dendrolimi were released on corn fields in Shenyang, Liaoning Province in the 2012 and 2013 cropping seasons. [Results] In 2012, there was no significant difference (P≥0.05) in the level of control of the Asian corn borer achieved by the two strains; the thelytokous strain reduced first and second generation Asian corn borer abundance by 66.3%, and 69.53%, respectively c.f. 56% and 79.73% for the arrhenotokous strain. Similarly, in 2013, the thelytokous strain reduced first and second generation Asian corn borer abundance by 56.20% and 82.10% c.f. 52.24% and 75.71% for the arrhenotokous strain. Nor was there a significant difference in the extent of crop damage between two strains (P≥0.05); in 2012 22.50% of the corn crop treated with the thelytokous strain was damaged c.f. 27.50% of the crop treated with the arrhenotokous strain , comparable values for 2013 were 38.28% and 21.09%, respectively. [Conclusion] The similar results achieved by both strains can be attributed to their high population growth rates, easier establishment at low wasp population densities, and the reduced costs of a mass rearing program. The thelytokous strain may have greater potential for application.