Phenology and Population of Strawberry Mites and Effectiveness of Using Strawberry Protection in the Conditions of the Right-Bank Forest-Steppe of Ukraine

Abstract

Growing strawberries is a promising and profitable field of agriculture. However, there are a number of limiting factors that determine the productivity of the crop, in particular pests-phytophages. The study aims to determine the features of the phenological phases of strawberry mite (Tarsonemus fragariae) and to examine the effect of protection on the population of phytophagous mites, the impact on physiological and biochemical processes in strawberry plants Murano and Vivara. The study is based on generally accepted methods in entomology and ecology. The degree of damage to strawberry plants was determined on a five-point scale, which on average for 2016-2020 was estimated at 0-1 point. A phenological map of strawberry mite development was created, the dependence of phytophage phenophases on weather conditions was established. In the Murano strawberry plantations, the average population of strawberry mite eggs in 2016-2020 was in the range of 105.3-165.0 pcs/100 leaves, larvae – 37.0-61.3 pcs/100 leaves, imago – 20.8-96.3 pcs/100 leaves. In the Vivara strawberry plantations, the population of mite eggs was in the range of 90.8-180.0 pcs/100 leaves, larvae – 37.0–57.0 pcs/100 leaves, imago – 17.3- 95.3 pcs/100 leaves. The effectiveness of the chemical plant protection systems under study (Masai® (0.4 kg/ha) + Biskaiia® (0.8 L/ha); Apollo® (0.5 l/ha) + Tsezar™ (0.2 L/ha) + Mavrik™ (0.6 l/ha)) against phytophage mites was almost at the same level. The exception was a direct ovicidal effect of the Masai and a mixture of Apollo + Tsezar; on the 3rd day after their introduction, the larvae in the eggs were unviable and the eggshells were mummified. The application of strawberry protection systems ensured berry yields of 33.4 t/ha in the Murano variety and 25.4-25.6 t/ha in the Vivara variety and a yield increase of 16.6-16.7 t/ha and 12.4-12.5 t/ha, respectively. The positive effect of plant protection systems against pests on the indicators of physiological and biochemical processes in the leaves of strawberries of both varieties was established. An increase in the content of chlorophyll by 33-58%, phenolic compounds – by 7-15%, sugars – by 6-10%, vitamin C – by 2-6% compared to the control was recorded in strawberry leaves. Given the high environmental safety requirements for berry growing technologies, the search for alternative biological products in the control of Tarsonemus fragariae is promising