Akademik Veri Yönetim Sistemi
Black Sea Journal of Agriculture, cilt.6, sa.2, ss.183-189, 2023 (Hakemli Dergi)
The green shield bug (GSB) (Palomena prasina, Hemiptera: Pentatomidae) is one of the most important pests of hazelnut in Turkish hazelnut orchards. This harmful insect causes serious yield and quality losses by feeding directly on fruits every year. Their feeding on hazelnut fruits may result in nut abortion (empty nuts) in early season and cause shriveled and corked kernels in kernel expansion period. Insect pest management must be decided by depending on insect population level in field according to integrated pest management concept. Economic injury level (EIL) and economic threshold (ET) are the main essential points that must be considered in decision for insect pest control. Thus, it can be possible to protect the natural environment from unnecessary pesticide applications and the growers from high production costs. Therefore, determining of economic decision levels for controlling pests is critical. This is especially important for hazelnuts, which are grown on hundreds of thousands of hectares of land in Türkiye, and for the GSB, a serious pest that requires a couple of chemical applications per year. The economic decision levels vary mainly due to insect species and their damage potential, crop value in the market and control costs which can change over years and countries. This study aimed to calculate the EIL and ET values for GSB control action in hazelnut orchards in Türkiye using new economic market data. Based on previous research, the authors calculated the yield loss caused by one individual of GSB in this study. Direct yield loss, as well as quality and quantity losses from damaged kernels, were calculated separately and then totaled. The data, including crop value and control costs necessary for calculation was updated from free market sources. In the calculation of EIL/ET, the most common formula (EIL= C/ VxbxK) was used. As a result, the economic threshold for a single insecticide application was determined to be3.8 insect/da (=0.1 ha) for K=1 value and 4.76 insect/da for K=0.8 value, for single insecticide application. When ET values were converted in traditional Turkish approach that is special for hazelnut orchards; ET values for K=1 and K=0.8 were 0.76 insect/ 10 “hazelnut “ocak” (traditional growing of hazelnut plants together) and 0.95 insect/ 10 “ocak” respectively. If 2 applications per year for GSB were considered, ET values were doubled up and calculated to be 7.6 and 9.47 insect/da for K=1 and K=0.8 value respectively, and thusly 1.52 and 1.9 insect/ 10 “ocak” for Türkiye. For practical reasons, the ET value for GSB was recommended as 10 insect/da and 2 insects/10 “ocak”, for Türkiye, with consideration of 2 chemical applications and K= 0.8.