Grez A A, González R H
Depto. Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
Depto. Sanidad Vegetal, Facultad de Ciencias Agrarias y Forestales, Universidad de Chile, Casilla 1004, Santiago, Chile.
Oecologia. 1995 Sep;103(4):471-474. doi: 10.1007/BF00328685.
The resource concentration hypothesis (Root 1973) predicts that specialist herbivorous insects should be more abundant in large patches of host plants, because the insects are more likely to find and stay longer in those patches. Between August 1989 and January 1990 we experimentally tested Root's hypothesis by analyzing the numerical response of four species of herbivorous insects associated with patches of 4, 16, 64 and 225 cabbage plants, Brassica oleracea var. capitata. In addition, we studied the colonization of patches by adults of Plutella xylostella (L.) (Lepidoptera: Plutellidae), and the migration of their larvae in patches of different sizes. No herbivorous insect densities differed significantly with patch size. Adults of P. xylostella colonized all kind of patches equally. Larvae did not migrate between patches, and their disappearance rate did not differ between patches. The resource concentration hypothesis is organism-dependent, being a function of the adult and juvenile herbivore dispersal behavior in relation to the spatial scale of patchiness.
资源集中假说（鲁特，1973年）预测，专食性食草昆虫在大片寄主植物中数量应更多，因为昆虫更有可能在这些斑块中找到食物并停留更长时间。1989年8月至1990年1月期间，我们通过分析与4株、16株、64株和225株甘蓝（Brassica oleracea var. capitata）植株斑块相关的4种食草昆虫的数量反应，对鲁特的假说进行了实验检验。此外，我们研究了小菜蛾（Plutella xylostella (L.)，鳞翅目：菜蛾科）成虫在斑块中的定殖情况，以及其幼虫在不同大小斑块中的迁移情况。食草昆虫的密度在不同斑块大小之间没有显著差异。小菜蛾成虫在各类斑块中的定殖情况相同。幼虫不会在斑块之间迁移，且其消失率在不同斑块之间也没有差异。资源集中假说是依赖生物体的，它是成年和幼年食草动物扩散行为相对于斑块空间尺度的函数。
