Pest management is one of the biggest challenges in the plant protection of sweet corn cultivation. The most destructive insect pests of sweet corn in Hungary are European corn borer (Ostrinia nubilalis Hbn.) and the corn earworm (Helicoverpa armigera Hbn.). Damage caused mainly by larvae. Chewed corn cobs are unmarketable, and a significant yield loss can also occur. Chemical insecticides control is the most widespread, but the demand for the use of the biological method is increasing. The aim of the present work is to compare the effectiveness of the conventional chemical method and the biological control by egg-parasitic wasps, Trichogramma pintoi, T. evascens (Trichoplus capsules) under operating conditions. The research was carried out in the growing season of 2019 and 2020 in the area of Csárdaszállás-Gyomaendrőd settlements (SE Hungary). We monitored the imagos of both species using pheromone and food traps. The number of damaged corn cobs was counted on the day of harvest in the sample areas. The cob damage ratio data were analyzed using the SPSS Generalized Linear Model using a One-way, Random Block Design ANOVA method. The number of H. armigera caught peaked at the end of July in both years, while O. nubialis only started to appear in the traps at that time. Chemical control was carried out twice in 2019, which was overall more effective than the Trichoplus treatment. The proportion of damaged corn cobs was 7.2% and 9.5%, which is a significant but not a large difference. Due to very rainy weather in 2020, only one insecticide treatment was performed in conventional cultivation. This did not provide adequate protection, the proportion of damaged corn cobs exceeded 20%. Biological control, which takes into account trap signalling, was more successful this year than chemical control, but even in addition, significant damage of nearly 15% occurred.

cob protection, Trichogramma, sweet corn, insect pests

biology

Presentation: poster