Stress Ecology Research Programme National Botanical Institute, c/o University of Cape Town, 7700, Rondebosch, South Africa.
J Chem Ecol. 1993 May;19(5):893-906. doi: 10.1007/BF00992526.
Aqueous leachates derived from canopy phyllodes of invasiveAcacia cyclops affected growth of a range of shrub species independently of nutrient input effects. All plants showed a sublethal phytotoxic response. Root mass was generally less adversely affected than shoot mass and, while decreasing significantly in response to the 10% concentration, showed no such response to the 1% solution. Root-shoot biomass ratios increased, except inEuphorbia burmannii, which may recognize intrinsic root architecture limitations on extensive exploitation of toxin-free soil. Application of surface plant litter from underA. cyclops canopies stimulated the production of basal stems inProtasparagus capensis andEriocephalus racemosus but was insufficient to significantly reduce root-shoot ratios. Plant growth inhibition was maximized by canopy leachate compounded by surface litter effects inAnthospermum spathulatum. The net effect of leachate at high concentration on biomass allocation in certain shrub species may help explain their patterns of association and disassociation withA. cyclops.
冠层叶状柄浸出液会影响入侵物种 Cyclops 金合欢的一系列灌木物种的生长，而不受养分输入效应的影响。所有植物都表现出亚致死的植物毒性反应。与地上部分相比，根质量通常受影响较小，而且虽然对 10%浓度的浸出液反应显著，但对 1%的溶液没有反应。根-茎生物量比增加，除了在Euphorbia burmannii 中，这可能是因为它认识到内在的根系结构限制了对无毒土壤的广泛利用。从 Cyclops 金合欢树冠下表面植物凋落物的应用刺激了Protasparagus capensis 和Eriocephalus racemosus 产生基茎，但不足以显著降低根-茎比。在 Anthospermum spathulatum 中，冠层浸出液与表面凋落物的综合作用使植物生长抑制达到最大。高浓度浸出液对某些灌木物种生物量分配的净效应可能有助于解释它们与 Cyclops 金合欢的关联和分离模式。
