Predicting the development of critical biological stages of Sunn pest, Eurygaster integriceps Put. (Hemiptera: Scutelleridae), by using sum of degree-days for timing its chemical control in wheat

This investigation was carried out for possible use of sum of degree-days (total effective temperatures) in order to predict the critical biological stages in chemical control of Sunn pest, Eurygaster integriceps Put. (Hemiptera: Scutelleridae), in 28 wheat fields of Adıyaman, Diyarbakır, and Şanlıurfa provinces from 2007 to 2010, and in climate chamber conditions. Development threshold temperature (°C) of Sunn pest in terms of the life span, starting from egg to new generation of adults, was found as 13.30 °C. Sums of degree-days starting from 1 January to appearance of the eggs, first-stage nymphs (n1 ), second-stage nymphs (n2 ), and fourth-stage nymphs (n4 ) were found with the averages of 44.6, 84.4, 123.3, and 223.1 degree-days, respectively. The results from the field studies reflected that developmental biological data on sum of degree-days as a predictive tool could be useful in better decision making to start chemical applications as soon as the appearance of n1 until n4 for Sunn pest control.This investigation was carried out for possible use of sum of degree-days (total effective temperatures) in order to predict the critical biological stages in chemical control of Sunn pest, Eurygaster integriceps Put. (Hemiptera: Scutelleridae), in 28 wheat fields of Adıyaman, Diyarbakır, and Şanlıurfa provinces from 2007 to 2010, and in climate chamber conditions. Development threshold temperature (°C) of Sunn pest in terms of the life span, starting from egg to new generation of adults, was found as 13.30 °C. Sums of degree-days starting from 1 January to appearance of the eggs, first-stage nymphs (n1 ), second-stage nymphs (n2 ), and fourth-stage nymphs (n4 ) were found with the averages of 44.6, 84.4, 123.3, and 223.1 degree-days, respectively. The results from the field studies reflected that developmental biological data on sum of degree-days as a predictive tool could be useful in better decision making to start chemical applications as soon as the appearance of n1 until n4 for Sunn pest control