Goal. To study the effectiveness of modern fungicides against the most common diseases of soybeans during the growing season and their effect on crop productivity in the Forest-steppe of Ukraine. Methods. Field, phytopathological, statistical. The experiments were carried out in the farms of the Kyiv region, belonging to the Forest-steppe zone of Ukraine. Spraying of soybean crops was carried out twice during the growing season in the phases of budding-beginning of flowering (51—55) and the formation of beans (71—75). Determined the development of diseases, the effectiveness of fungicides, crop yield. Results. The most common diseases of soybeans in the forest-steppe zone of Ukraine have been identified: Alternaria, downy mildew, Fusarium wilting, Septoria, and bacterial blight. The species composition of diseases and the degree of their development were largely influenced by the weather conditions of the growing season. The investigated fungicides Abacus mk.e. (pyraclostrobin, 62.5 + epoxiconazole, 62.5), Amistar Extra 280 SC, (azoxystrobin, 200 + cyproconazole, 80), Acanto Plus 28 c.s. (picoxystrobin, 200 g/l + cyproconazole, 80 g/l), Coronet 300 SC (trifloxystrobin, 100 g/l + tebuconazole, 200 g/l), as well as Impact K preparations, c.s. (flutriafol, 117.5 g/l + carbendazim, 250 g/l) and Koside 2000 w. g. (copper hydroxide, 350 g/kg) at the recommended application rates effectively limited the development of most fungal pathogens. The highest protective effect of 69.8—78.9% of fungicides was shown against downy mildew of soybeans, the lowest — 31.7—42.2% against Alternaria, which had the highest development in comparison with other diseases. Fungicide Koside 2000 w. g. at the level of 67% limited the development of bacterial diseases. The use of fungicides had a positive effect on the yield of soybeans. Due to the limitation of the development of diseases, the soybean yield increased by 21.2—30.3%, depending on the variant of the experiment. Conclusions. The use of fungicides significantly affected the limitation of the development of the most common soybean diseases in the Forest-steppe of Ukraine. The effectiveness of The effectiveness of the studied modern fungicides against peronospora, fusarium wilting, septoria was at the level of 60.2—78.9%. Fungicides most effectively controlled the development of downy mildew, less effectively — the development of Alternaria. The limitation of soybean diseases when using fungicides contributed to an increase in its yield by an average of 0.7—1.0 t/ha.

Goal. Evaluation of the suitability and eggs of chestnut moth Cameraria ohridella for parasitism and development of trichogramma. Methods. Laboratory cultures of Trichogramma pintoi Voeg were used for research. and Trichogramma evanescens Westw., which were bred on the eggs of Sitotroga cerealella Oliv. The experiment was performed according to the following scheme: female trichogramma after mating was placed in a test tube in 5 replicates for each species. The tube was closed with a stopper and the sex of individuals under binoculars was checked. In test tubes with trichogram laid strips of paper with one-day eggs of chestnut moth (25 copies.). In 5 replicates and kept in a thermostat (temperature — 24—25°C; relative humidity — 65—67%). The percentage of trichogram revival and the ratio of males to females, life expectancy and fertility of females were determined. Trichogramma individuals, which were fed with grain moth eggs, served as controls. The experiment lasted until the complete death of the trichogram. The obtained results were processed statistically according to standard methods. Results. A small number of chestnut moth eggs pierced by trichogramma were detected, but embryonic development of the parasite’s eggs was not observed. Comparing the size of the eggs of the chestnut moth with the size of the eggs of the main squamous pests against which different species of trichogramma are effectively used, we can conclude that for the successful development of eggs T. pintoi and T. evanescens chestnut moth eggs are not suitable as feeders. Probably, in terms of size and biological quality, they do not correspond to the parameters of the ecological niche of the hosts of the family Trichogrammatidae. Conclusions. In the laboratory, it was found that the eggs of the chestnut moth are not suitable for parasitizing the trichogramma of T. pintoi and T. evanescens. The main pests of crops, which are effectively parasitized by different species of trichogramma, have an egg size in the range of 0.4—1.0 mm, while the size of chestnut moth eggs does not exceed 0.27—0.32 mm. It is possible that the size and biological quality of chestnut moth eggs do not meet the parameters of the ecological niche of entomophagous feeders of the family Trichogrammatidae. Further researches with use of various types of a trichogramma, first of all — T. dendrolimi Mats appear actual.