Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Effects of pine needle gall midge, Thecodiplosis japonensis Uchida et Inouye (Diptera: Cecidomyiidae), infestation on the shoot and needle growth of Pinus densiflora Sieb. et Zucc.

Abstract

Data on needle and shoot growth for Pinus densiflora saplings in Kang-Won Province, Korea Republic, were collected at bimonthly intervals from late April through mid-August, in 1995 and 1996. In comparison with healthy needles which elongated linearly from early May to mid-August, needles infested with the pine needle gall midge stopped elongating in early July. Severe infestations in the previous year reduced shoot and needle growth, and delayed needle elongation. Delayed elongation of needles prolonged the synchrony between emergence of pine needle gall midge adults and the optimal length of needles for oviposition. This may be a critical factor in causing continuous infestations.