Effects of temperature and nonionizing ultraviolet radiation treatments of eggs of five host insects on production of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) for biological control applications.

Authors: EDWIN, EDWARD-SAM - Manonmaniam Sundaranar University (MSU); VASANTHA-SRINIVASAN, PRABHAKARAN - Manonmaniam Sundaranar University (MSU); PONSANKAR, ATHIRSTAM - Manonmaniam Sundaranar University (MSU); THANIGAIVEL, ANNAMALAI - Manonmaniam Sundaranar University (MSU); SELIN-RANI, SELVARAJ - Manonmaniam Sundaranar University (MSU); Mankin, Richard; SENTHIL-NATHAN, SENGOTTAYAN - Manonmaniam Sundaranar University (MSU); KALAIVANI, KANDASWAMY - Manonmaniam Sundaranar University (MSU); MURALI-BASKARAN, RAMASAMY - Indian Council Of Agricultural Research (ICAR); DURAIPANDIYAN, VEERAMUTHU - King Saud University; AL-DHABI, NAIF - King Saud University

Submitted to: Journal of Asia-Pacific Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/2016
Publication Date: 10/1/2016
Citation: Edwin, E., Vasantha-Srinivasan, P., Ponsankar, A., Thanigaivel, A., Selin-Rani, S., Mankin, R.W., Senthil-Nathan, S., Kalaivani, K., Murali-Baskaran, R.K., Duraipandiyan, V., Al-Dhabi, N.A. 2016. Effects of temperature and nonionizing ultraviolet radiation treatments of eggs of five host insects on production of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) for biological control applications. Journal of Asia-Pacific Entomology. doi:10.1016/j.aspen.2016.09.011.
DOI: https://doi.org/10.1016/j.aspen.2016.09.011

Interpretive Summary: Trichogramma parasitic wasps are used as biological control agents against insect pests worldwide. Improved rearing methods are needed to increase the efficacy and efficiency of Trichogramma for augmentative mass releases in fields and warehouses. Scientists at the USDA, Agricultural Research Service, Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, Florida, and the Manonmaniam Sundaranar University in India, examined the benefits of pretreating eggs of four different Trichogramma host species to reduce the host’s resistance to parasitization and improve the quality of released parasitoids. Pretreatment of the eggs with high temperatures or ultraviolet (UV) radiation demonstrated that a greater fraction of Oriental leafworm moth eggs were parasitized than for other species at all tested temperatures. However, the maximum percentage of emergence and viability was observed with rice moth eggs treated with UV. This research shows that mass production of Trichogramma can be improved and provides a guide for future efforts towards improved augmentative mass releases of these parasitoid wasps to control insect pests in crops and warehouses.

Technical Abstract: Trichogramma are used worldwide as biological control against insect pests, attacking eggs of over 200 species. Eggs of Spodoptera litura, Corcyra cephalonica, Plutella xylostella and Helicoverpa armigera were tested to consider the effect of temperature and radiation on parasitization, emergence of adult and viability of T. chilonis under in vitro conditions. At constant temperature (24, 28, 32°C), the percent parasitization of T. chilonis was significantly greatest on the eggs of S. litura. The percent emergence of T. chilonis was significantly greater in C. cephalonica. The percentage of adult viability was found to be 83.9% from C. cephalonica eggs grown at 28°C. Non-ionizing radiation (3, 6, 9 minutes at 254 nm) treatment increased the parasitization percentage, which was significantly greater on the eggs of C. cephalonica (63%) than on eggs of the other hosts. The adult emergence and viability of T. chilonis were observed higher on C. cephalonica eggs exposed to non-ionizing radiation compared to all other species. In studies comparing effects of temperature and non-ionizing radiation, maximum parasitization, emergence and viability was observed in C. cephalonica eggs that had been treated with UV. This treatment method can enhance the efficiency of use of T. chilonis biological control in agricultural field and storage warehouses.