HOST WEEDS FOR SUNN PEST (EURYGASTER INTEGRICEPS PUT.) IN OVERWINTERING AREAS ON SAVUCAK MOUNTAIN

Abstract

On Savucak Mountain, particularly from 1300-1400 m, many plants have left their sites to gum tragacanth (Astragalus gummifer Lab.) and prickly thrift [Acantholimon acerosum (Willd.) Boiss.], which forms are generally 70 cm thick, perennial and bushy. Under these weeds and 2-4 cm depth of the soil are found sunn pest (Eurygaster integriceps Put.), which is the main pest of the Diyarbakir wheat fields. Sunn pest is a bug with a life cycle of one year, and adults have two life stages, active and passive. The active period lasts for about 3 months and in cereal fields. The passive period lasts for 9 months and passes under the dominant weeds forming cover in the sections of 1300-1700 m height. The study was aimed to determine the frequency (%) and density (plant number m-2) of A. gummifer and A. acerosum weeds in the forested and bare areas of Savucak Mountain. For this purpose, in October 2015 and March 2016, surveys were carried out on Mount Savucak, located in the district of Cungus, Diyarbakir province. The frequency and density of the occurrence of A. gummifer and A. acerosum in the forestless wintering areas of Savucak Mountain (% 29 – 0.59 m-2 and 13% - 0.38 m-2) were found higher than forested wintering areas (7 – 0.23 m-2 and 2 – 0.07 m-2). The reason for this reduction seen in the distribution of both alien species in the forested areas in winter may be that the weeds can not compete adequately for light, water, and nutrients with relatively high-structured trees. A. gummifer and A. acerosum weeds, both of which are host to sunn pest, were suppressed by afforestation in the Savucak Mountain wintering areas and this region which is known to be under risk of desertification could be protected and can be protected.