文章基本信息

标题：Effects of Lotus tenuis density upon the emergence, survival and cover of Cirsium vulgare
本地全文：下载
作者：Elizabeth Ortega ; Pablo Vergara ; Osvaldo Vignolio 等
期刊名称：Ecología Austral
印刷版ISSN：1667-782X
电子版ISSN：1667-7838
出版年度：2000
卷号：10
期号：2
页码：143-149
出版社：Asociacion de Ecologia Argentina
摘要：After burning for raising the stocking rate, the Paspalum quadrifarium-dominated grasslands of the Flooding Pampa become invaded by a forage legume, Lotus tenuis, and /or by Cirsium vulgare among other weed species. Aiming to compare the relative impact of L. tenuis on pre and post-emergence stages of C. vulgare, the emergence, survivorship and coverage of C. vulgare were evaluated in response to four sowing densities of L. tenuis (0.0; 0.25; 0.5 and 1.0 seeds/cm2) and two spatial patterns of C. vulgare (15 uniformly distributed seeds within a circle of 5 cm diameter or on a circle of 28 cm diameter), by using a factorial design under greenhouse conditions. The emergence of C. vulgare lineally declined with increasing densities of L. tenuis, independently of its spatial pattern of sowing. While the emergence of C. vulgare was reduced up to 40% by the presence of L. tenuis, the effects of this species on the seedling mortality of the emerged seedlings reached up to 270% of increment. In contrast with the emergence, which was mostly affected by the maximum densities of L. tenuis, the final coverage of C. vulgarewas similarly reduced for the presence of L. tenuis irrespective of its density. These results confirm the occurrence of pre-emergent effects of L. tenuis seeds on C. vulgare seeds, as previously detected under laboratory conditions, even under potentially adverse conditions for the activity of allelopathic compounds