الخسارة الاقتصادية لحشرة حميرة النخيل Batrachedra amydraula Meyrick (Lepidoptera: Cosmopterygidae) على نخيل التمر صنفي خستاوي وزهدي في وسط العراق

Abstract

The results showed that average number of fruits in Zahdi was 30801 fruit / tree at the last week of April and became 17238 fruit / tree at the second week of July . Of the 15349 fallen fruit / tree there were 980 infested fruits which amounts to a percentage economic loss of 5.37% equaling about 7.84 kg / tree . Where as in Khastawi there were 29844 fruit / tree at the first week of May and became 11200 fruit / tree at the end of July ، so that the number of fallen fruits were 18644 of which 6702 were infested amounting to a percentage economic loss of 37.43% equaling 44.68 kg / tree. The study indicated a significant positive relationship between number of larvae and number of fallen infested fruits . It was averaged between 0.004 – 12.76 larvae / 100 fallen infested fruits in Zahdi , and 0.43 – 32.02 larvae / 100 fallen infested fruits in Khastawi , when the percentage of infestation in fallen fruits was 0.2 – 45.6% and 5.4 – 94.2% in Zahdi and Khastawi respectively . Coefficient of correlation (r) was 0.990 in Zahdi and 0.994 in Khastawi