The phytosanitary status of spring oilseed rape in the conditions оf north-eastern forest-steppe of Ukraine

The dynamics reflecting the number of spring oilseed rape pests in the conditions of north-eastern forest-steppe of Ukraine during 2005‒2018 was analyzed. The method of the research was general. The most common insect pests of spring rape crops are Pollen beetles (Meligethes aeneus F.), Flea beetles (Phyllotreta spp.), Turnip sawflies (Athalia rosae L.). The Flea beetles settled 100 % of the growing area during the seedling stage. The Flea beetles damaged 12.0‒35.0 % of the rape crops. The highest pest damage was 67.0 % in 2006, and 66.0 % in 2005. The number of Flea beetles was 3.0‒5.0 specimens per m2, and the largest number was 18.0 specimens per m2 in 2006. The Pollen beetles settled 100.0 % of the plants; in 2006 they settled 85.0 % of the plants, and in 2010 the pests settled 91.0 % of the plants during the period of budding and flowering. The Pollen beetles damaged 17.0‒37.0 % of the rape crops. The highest pest damage was 74.0 % in 2006, 69.0 % in 2005, and 63.0 % in 2007. The number of Pollen beetles was 2.0‒6.0 specimens per plant, and the largest number was 30.0 specimens per plant in 2006. The number of Turnip sawflies among the specialised oilseed rape pests was the least. Turnip sawflies settled 100.0 % of the plants only in 2005, and in 2008 the beetles settled 64.0 % of the plants. During the research period the Turnip sawflies settled mainly within 14.0‒50.0 % of the rape crops. The flies damaged 3.0‒8.0 % of the plants. The number of Turnip sawflies was 0.9‒2.0 specimens per plant. The largest number of pests was 7.0 specimens per plant in 2006, and slightly less – 4.0 specimens per plant in 2007. In Sumy region in the years 2005‒2018 the sowing area of spring oilseed rape varied within 1.1‒22.2 thousand hectares, and total yield of oilseed rape – 1.9‒22.3 thousand tonnes. Protection measures against spring rape crops pests include preventative and extarmination methods. To protect rape crops against the Flea beetles during the seedling stage some insecticidal chemical means are used. During the growing season the rape crops are sprayed with insecticides against the Flea beetles (3‒5 beetles per m2), Pollen beetles (5‒6 beetles per plant), and Turnip sawflies.