Stefan Rashev1, Nedyalka Palagacheva2, Stoyan Georgiev1, Sara Ivanova1 and Valentina Dimitrova1
1 Agricultural Academy, Field Crops Institute, Chirpan, Bulgaria
2 Agricultural University – Plovdiv, Bulgaria
Abstract
Rashev, S., Palagacheva, N., Georgiev, S., Ivanova, S. & Dimitrova, V. (2026). Efficacy of plant extracts against adults of the pollen beetle (Brassicogethes / Meligethes aeneus F.) and the red cabbage bug (Eurydema ornata L.). Bulg. J. Agric. Sci., 32(1), 114–121
Despite its many advantages as a crop, oilseed rape is host to a large number of pests that can cause economically significant losses.
The pollen beetle (Brassicogethes/Meligethes aeneus F.) is one of the species of economic importance as an pest of oilseed rape during its mass multiplication. In some years, the red cabbage bug (Eurydema ornata L.) is also found en masse.
The repeated use of insecticides used in oilseed rape agrocenosis, often leads to the development of resistance, the destruction of beneficial entomofauna and pollinators, which is why alternative means are sought.
In this regard, the efficacy of plant extracts of ginger (Zingiber officinale L.), peppermint (Mentha piperita L.) and nettle (Urtica dioica L.) was tested against the pollen beetle (Brassicogethes/Meligethes aeneus F.) and the red cabbage bug (Eurydema ornata L.).
The study was carried out under laboratory conditions at the Agricultural University-Plovdiv. The attempt was made in four variants and three repetitions. The processing of the obtained data was carried out with a package of statistical programs Statistika 7 V.
Tested plant extracts affect the vitality of pests, which is due to species-specific alkaloids. In the case of the pollen beetle, the highest efficacy was reported for nettle and ginger – 99.7%, and for the red cabbage bug, mint and nettle – 83%. All plant extracts increase their efficacy gradually.
Keywords: plant extract; Zingiber officinale L.; Mentha piperita L.; Urtica dioica L.; Brassicogethes/Meligethes aeneus F.; Eurydema ornata L.