Can Trichogramma and entomopathogenic nematodes serve as effective biocontrol options for Helicoverpa zea in tomato?
Biocontrol for insect pest management (BIPM) was the maiden like method of pest control pre-dates the modern pesticide era. Controlled exotic pests by natural enemy species collected from the country or area of origin of the pest was one of the successful method in for BIPM. The potential of entomopathogenic nematodes (EPNs) and an egg parasitoid for biological control of eggs of tomato fruit worm Helicoverpa (= Heliothis) zea (Boddie), and the effect on fruit production after two years of
... r two years of field evaluation (2011-2012) revealed encouraging results. Trichogramma evanescens (Westwood), Steinernema carpocapsae (all strain) (Weiser) and Heterorhabiditis bacteriophora (HP88) (Poinar) were applied to control H. zea on tomato field. Two augmentation releases of each biological control agent at 15-day intervals, 15 days after tomato plants reach 30-50% effloresce were found effective. The percentage of fruits damaged by H. zea was significantly reduced in plots treated by egg wasp T. evanescens than either of S. carpocapsae or H. bacteriophora nematodes and control treatments. The efficacy of T. evanescens, S. carpocapsae, and H. bacteriophora differed significantly and S. carpocapsae nematode was found superior to H. bacteriophora. The healthy fruit yield in plots treated by H. bacteriophora was better than the fruit yield in plots treated by T. evanescens and S. carpocapsae. While as the average yield from healthy fruits/plants in plots treated by H. bacteriophora, T. evanescens and S. carpocapsae was better than the numbers in control plots. It was conducted that biological control in tomato for controlling H. zea using Trichograma and EPNs as one of the most promising alternatives to the present chemical based pest management. These biocontrol agents (H. bacteriophora, S. carpocapsae & T. evanescens) are easy to apply. Coast effective compared chemical pesticides, and turned out to be safe with high quality fruits.