Microbial biopesticides are considered natural elements of biological nature often used to control pests in various agroecosystems. In the present work, we proposed to test some biopesticides to see if they are effective in controlling relevant pests in organically grown corn. Among the frequent pests as target organisms, we considered aphids, chrysomelid (leaf) beetles and lepidopteran larvae. It is known that chemical products cannot be applied in an organic system, that's why we focused on 2 biopesticides (B1-Spinosad and B2-Bactospeine) in use and available on the European market. Thus, in 3 repetitions consisting of different doses, we did tests directly in the field using special cages. I made the observations periodically on 3, 5, 7, 9 and 11 days from July-August, during the year 2022, in a corn crop in Arad County (in western Romania). The effectiveness results were interpreted by the survival rate of the larvae and by the mortality rate. It turned out that both B1 as well as B2 are effective in higher doses. The low survival rate of the targeted pests automatically meant a high mortality rate and vice versa. The efficacy data by the mortality rate were varied depending on the category of pests (64.47%/B1 and 45.56%/B2 for lepidopteran larvae, 40.06%/B1 and 31.12/B2 for chrysomelids and 36.89%/B1 and 45.33% /B2 in aphids). It is clear that where the mortality rate was higher it is the ideal option to be included in the pest control strategy in the maize crop. Of course, a single application is not enough, that's why we recommend a double treatment at an interval of 10-14 days.

microbial biopesticides, pests, corn, field, bioefficacy.

agronomy

Presentation: poster