Biology and control of the fruit borer, Conopomorpha sinensis Bradley on litchi (Litchi ch

Biology and control of the fruit borer, Conopomorpha sinensis Bradley on litchi (Litchi

chinensis Sonn.) in northern Thailand

MARIE JOY SCHULTE;KONRAD MARTIN;JOACHIM SAUERBORN

【期刊名称】《中国昆虫科学：英文版》 【年(卷),期】2007(014)006

【摘要】Fruit and leaf shoot of litchi (Litchi chinensis) infestation by naturally occurring populations of the fruit borer, Conopomorpha sinensis larvae and C. sinensis parasitization rates were determined in litchi orchards in northern Thailand at high (ca. 1 400 m ASL) and low (ca. 800 m ASL) elevations with different, non-overlapping fruiting seasons. In addition,spray applications of Bacillus thuringiensis var. aizawai, the natural compound spinosad and the chemical pesticide imidacloprid were conducted in the field to test the effects of these agents on C. sinensis fruit infestation rate. Fruit infestation rate and fruit growth, studied in a low elevation orchard, were sigmoidal and showed a highly significant positive correlation (P ≤ 0.01). Leaf shoot infestation rate in the low elevation orchard decreased in the course of the fruiting season (March until May), but increased in the high elevation orchard, where no fruits were present within the same period of time. Together, these results indicate that females of C. sinensis clearly prefer fruits over shoots for oviposition. If no fruits are available, which was the case in