Japonski dresnik (Fallopia japonica [Houtt.] ronse decraene) in njegovo zatiranje z bolšico Aphalara itadori Shinji

Abstract

European Environment Agency composed the list of 163 most important invasive organisms, that are threatening European ecosystems. One of above mentioned invasive species is also the plant Japanese knotweed (Fallopia japonica), which grow on different soil types. In ruderal habitats the plant is most prevalent, however because of its competitive position the Japanese knotweed is becoming more and more important part of the ecosystems, because it is superseding indigenous species. Mechanical removal is only temporary solution of its extermination. While this plant species grows in urban areas and near the water, numerous researchers see the long-term solution of its extermination in biological control of this weed with introduction of natural enemy from its origin. In Japan Japanese knotweed has about 180 different natural enemies but only the psyllid Aphalara itadori has been prooved to be effective. Young larvae are the most damaging stage of the insect. With sucking of the plant juice, plant is not destroyed, it only develops slower. In Great Britain, which is the first area in Europe, where the above mentioned psyllid was introduced, species also overwinters in the open. The introduction od Aphalara itadori represent the first example of classical biological control of weeds not only in Europe but also worlwide.