Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế, đề tài: aggregation by Tomicus piniperda L (Col: Scolytidae) in Yunnan, southwestern China. | Ann Sei For 1997 54 635-641 Elsevier Inra 635 Original article Shoot aggregation by Tomicus piniperda L Col Scolytidae in Yunnan southwestern China Y Hui F Lieutier2 1 Yunnan University Institute of Ecology and Geobotany Kunming Yunnan PR China 2Station de zoologie forestiere Inra Ardon 45160 Olivet France Received 27 August 1996 accepted 13 March 1997 Summary - In Pinus yunnanensis forests of Yunnan southwestern China ten trees with evident symtoms of heavy shoot attacks by Tomicus piniperda were selected in two localities. Around each of these trees five others of similar size and similar morphological and site characteristics and as close as possible to the attacked trees were chosen to be used as a control. For all trees shoots were investigated for damage. No brood tree was present in the vicinity of the sampled trees attacked or control . The percentage of the shoots damaged by Tpiniperda ranged from to in the attacked trees whereas it ranged from to in the control trees thus exhibiting an aggregation phenomenon during the beetle shoot-feeding period. There was no evidence of an effect of tree height and wind direction on aggregation. The percentage of damaged shoots in the control trees decreased with distance from the shoot-aggregation trees. Aggregation seemed to occur almost at the end of the shoot-feeding period suggesting that it could play a critical role in weakening the tree explaining the subsequent successful mass attack that always takes place in the bole of such trees and kills them. It could thus explain the very unusual nocivity of Tpiniperda in southern China. China Tomicus piniperda I Pinus yunnanensis shoot attack aggregation Resume - Agrégation de Tomicus piniperda Col Scolytidae sur pousses dans le Yunnan Chine méridionale. Dans deux localités des forets de Pinus yunnanensis du Yunnan Chine du Sud dix arbres ont été choisis parce qu ils étaient de toute evidence I objet d importantes attaques par Tpiniperda au niveau des
