Ganade G, Brown V K
Department of Biology and Centre for Population Biology, Imperial College at Silwood Park, Ascot, Berkshire, SL5 7PY, UK, , , , , , GB.
International Institute of Entomology (An Institute of CAB INTERNATIONAL) 56, Queen's Gate, London SW7 5JR, UK, , , , , , GB.
Oecologia. 1997 Feb;109(3):374-381. doi: 10.1007/s004420050096.
The effects of, and interactions between, insect root feeders, vesicular-arbuscular mycorrhizal fungi and soil fertility on the establishment, growth and reproduction of Vicia sativa and V. hirsuta (Fabaceae) were investigated in an early-successional grassland community. Seeds of both species were sown into plots where soil insecticide (Dursban 5G), soil fungicide (Rovral) and soil fertiliser (NPK) were applied in a factorial randomised block design. Fertiliser addition reduced growth, longevity and reproduction of both Vicia species, due to the commonly recorded increase in the competitive advantage of the non-nitrogen-fixing species when nitrogen is added to the plant community. However, in plots where fertiliser was not applied, a reduction in root feeders and mycorrhizal infection led to an increase in seedling establishment and fruit production of V. sativa, and to an increase in flower production for both Vicia species. The interaction between all three soil treatments explained much of the variation in growth and longevity of V. sativa. Plants grew larger and survived longer in plots where natural levels of mycorrhizal infection and root feeders were low compared with plots where all the treatments were applied. This suggests that, although soil nutrient availability was a strong determinant of the performance of these two leguminous species, at natural levels of soil fertility biotic factors acting in the soil, such as mycorrhizal fungi and soil-dwelling insects, were important in shaping the competitive interactions between the two Vicia species and the plant community. Our results indicate that non-additive interactions between ecological factors in the soil environment may strongly affect plant performance.
在一个早期演替的草地群落中，研究了昆虫根系取食者、泡囊-丛枝菌根真菌和土壤肥力对紫花野豌豆和硬毛野豌豆（豆科）的建立、生长和繁殖的影响及其相互作用。将这两个物种的种子播种到采用析因随机区组设计施用土壤杀虫剂（毒死蜱5G）、土壤杀菌剂（农利灵）和土壤肥料（氮磷钾）的小区中。添加肥料降低了两种野豌豆的生长、寿命和繁殖能力，这是由于在植物群落中添加氮时，非固氮物种的竞争优势通常会增加。然而，在未施用肥料的小区中，根系取食者数量减少和菌根感染减少导致紫花野豌豆的幼苗建立和果实产量增加，以及两种野豌豆的花产量增加。所有三种土壤处理之间的相互作用解释了紫花野豌豆生长和寿命的大部分变异。与施用所有处理的小区相比，在菌根感染和根系取食者自然水平较低的小区中，植物长得更大且存活时间更长。这表明，尽管土壤养分有效性是这两种豆科植物表现的一个重要决定因素，但在自然土壤肥力水平下，土壤中起作用的生物因素，如菌根真菌和土壤昆虫，在塑造两种野豌豆物种之间以及与植物群落的竞争相互作用中很重要。我们的结果表明，土壤环境中生态因子之间的非加性相互作用可能会强烈影响植物表现。
