Host tree and borehole site selection by the ambrosia beetle Platypus quercivorus

研究了日本栎树枯萎病病原菌的媒介害虫--文心虫对寄主树种和孔位的选择。田间研究表明，在较小的空间尺度上，茎密度对栗小蜂的攻击概率的影响是正的，而在较大的空间尺度上，茎密度的影响是负的。田间研究还表明，受侵害树密度对受侵害树的死亡率有正向影响。对受侵袭树木的连续观察表明，松材线虫在侵袭初期优先选择树的底部作为钻孔部位，但随着底部洞口密度的增加，其钻孔位置向更高的位置转移。

Host tree and borehole site selection by the ambrosia beetle Platypus quercivorus, the vector beetle of pathogenic fungi which cause Japanese oak wilt, were studied. A field study revealed that the effect of stem density on the probability of attack by P. quercivorus was positive at a small spatial scale, and negative at larger scales. A positive effect of attacked trees' density on the probability of mortality of attacked trees was also shown by a field study. Continuous observation of attacked trees revealed that P. quercivorus preferred the basal part of the tree as their borehole site in an early stage of attack, however, they changed the site of hole boring to the higher place with increasing density of holes at the basal part.