Abstract
Sucking insects are the most common pests and could affect a wide range of cultural and wild plants. They possess a big reproductive potential and under favourable climatic conditions can cause considerable damages on agricultural crops. Some of the sucking insects show resistance to chemical pesticides, which additionally makes their control difficult. To investigate the effect of natural pesticides on the population of some sucking insects in a two year`s field experiment was conducted in the region of the village Kliment on five years`s old organic rose plantation. The following products have been included in the investigation: Limocide® (60 g/L orange oil) NeemAzal® T/S (Nime-substance – 2.5 %) and 4 % bee glue solution. The field experiments were arranged according to the block method in four replications and plot size of 18 м2 (21 plants per variant). The population density of sucking insects varied depending on the climate conditions. The product Limocide® and the 4% bee glue solution managed to control the invasion of the two-spotted spider mite Macrosiphum rosae L. and proved their effectiveness against Thrips tabaci as well. The product that contain as azadirachtin as an active substance showed an unsatisfactory percentage of effectiveness against the target insects. The 4% bee glue solution has a great potential, and its mechanism of action needs to be further investigated.
Keywords: biological control, sucking insects, roses