Efficiency of chemical protection of spring rape and mustard from cruciferous bugs
Abstract
S.V. Stankevych*, V.V. Vilna, I.V. Zabrodina, T.V. Antonenko, I.P. Lezhenina, М.O. Filatov, H.V. Baidyk, L.Ya. Sirous, D.D. Yushchuk, V.O. Melenti, O.A. Molchanova, M.M. Dolya, L.M. Popova, T.O. Galagan and N.A. Zaharchuk
The complex of cruciferous bugs includes such species as painted or harlequin (cabbage) bug (Eurydema ventralis Kol), pentatomid rape bug (E. oleraracea L.), and mustard bug (E. ornata L.). They belong to Hemiptera, the family Shield bugs (Pentatomidae), and the genus Cruciferous bugs (Eurydema). The dominant species is the cabbage bug. The mustard bug dominated only in 2007, and since 2012 it has not been detected in the records. They are widespread throughout the whole territory of Ukraine. Both adult bugs and larvae cause damage to the crops; they pierce the leaf skin or floriferous shoots with the proboscis and suck out the juice. The light spots appear at the puncture points, the tissue dies, falls out, and the irregular form holes are formed. When the seeds are damaged, the flowers and ovary fall off, and the quality of the seeds deteriorates. The harmfulness of the bugs increases dramatically in dry and hot weather. As a result of the researches, it is found out that in 2012−2014 the average technical efficiency of the Biscaya preparation, 24% of oily dispersion on spring rape in 3 days after spraying was 87.7%, in 7 days it was 58,4%, and in 14 days it was 47.9%; on white mustard the technical efficiency was 92.2, 83.0, and 69.5% respectively. As for Chinese mustard, the efficiency was 92.4, 83.1, and 66.7%. The technical efficiency of the insecticides Mospilan, 20% of soluble powder and Nurelle D, 55% of emulsion concentrate is somewhat lower than that of the Biscaya insecticide, 24% of oily dispersion, and, depending on the cultivated crop, in 3 days the technical efficiency was 77.4–83.6% and 78.4–82 0% respectively, in 7 days it was 52.8–74.5% and 68.0–75.5%, in 14 days the efficiency was 49.1−65.5% and 49.0−62.0% respectively. At the Educational, Research and Production Centre “Research Field” spraying with the Biscaya insecticide ensured saving of the spring rape yield up to 0.249 t/ha, the yield of white mustard was saved at the level of 0.133 t/ha, and the yield of Chinese mustard was saved at the level of 0.201 t/ha. The applying of the Mospilan insecticide, 20% of soluble powder on spring rape crops contributed to saving the yield at the level of 0.317 t/ha, the yield of white mustard was saved at the level of 0.125 t/ha and the yield of Chinese mustard was saved at the level of 0.273 t/ha. Spraying with the preparation Nurelle D, 55% of emulsion concentrate ensured the yield up to 0.344, 0.093, and 0.261 t/ha, respectively.