Journal of Plant Protection Research

Abstract

The perspective direction in the biological regulation of insect pest populations is the combined use of different products of organic origin including fungal biological control agents. Therefore, the present study was aimed to evaluate the efficacy of products of natural origin (Aminogreen 24, Nitrogreen, Foliamin and Naturalis − strain ATCC 74040 of entomopathogenic fungus Beauveria bassiana) and one synthetic insecticide − standard (deltamethrin + thiacloprid), applied alone and in a mixture in the control of Acyrthosiphon pisum in forage pea. The study was conducted in a field experiment during the period 2017 − 2020. Infestation by leaf aphids was estimated by calculating the cumulative insect--days (CID). It was found that the combination of Aminogreen 24 + Naturalis had the most pronounced decrease in CID among products over the years from 2017 to 2020 and the average for the period. The greatest, significant reduction in the number of aphids occurred on day 5 (F 8.5 = 15.244; p < 0.033) and day 7 (F 8.5 = 33.087; p < 0.037) after treatment. On the 14th day, the decrease in CID (57.4% decrease) statistically exceeded the Proteus 110 OD standard (55.3% decrease) (F 8.5 = 49.841; p < 0.049). Good protection against A. pisum was also found with Naturalis and Nitrogreen + Naturalis. There was an additive effect between Naturalis and Aminogreen 24 throughout the entire study period. The ratio of chlorophyll a (Chl a) to chlorophyll b (Chl b) and the ratio of green pigments (Chl a + + Chl b) to carotenoids determined that plants treated with Aminogreen 24 + Naturalis and Naturalis had the best physiological state. The combination of Aminogreen 24 and Naturalis gave the largest, significant, increase in stem height, followed by Nitrogreen + Naturalis. The use of Naturalis, alone and in a combination with Aminogreen 24 and Nitrogreen can be a successful alternative to conventional chemical control.