caa a22 4500 469098236 CHVBK 20180323133037.0 cr unu---uuuuu 170328e19920801xx s 000 0 eng 10.1007/BF00317797 doi (NATIONALLICENCE)springer-10.1007/BF00317797 Density dependent interactions between VA mycorrhizal fungi and even-aged seedlings of two perennial Fabaceae species [Elektronische Daten] [N. Allsopp, W. Stock] Summary: The interaction of density and mycorrhizal effects on the growth, mineral nutrition and size distribution of seedlings of two perennial members of the Fabaceae was investigated in pot culture. Seedlings of Otholobium hirtum and Aspalathus linearis were grown at densities of 1, 4, 8 and 16 plants per 13-cm pot with or without vesicular-arbuscular (VA) mycorrhizal inoculum for 120 days. Plant mass, relative growth rates, height and leaf number all decreased with increasing plant density. This was ascribed to the decreasing availability of phosphorus per plant as density increased. O. hirtum was highly dependent on mycorrhizas for P uptake but both mycorrhizal and non-mycorrhizal A. linearis seedlings were able to extract soil P with equal ease. Plant size distribution as measured by the coefficient of variation (CV) of shoot mass was greater at higher densities. CVs of mycorrhizal O. hirtum plants were higher than those of non-mycorrhizal plants. CVs of the facultatively mycorrhizal A. linearis were similar for both mycorrhizal and non-mycorrhizal plants. Higher CVs are attributed to resource preemption by larger individuals. Individuals in populations with high CVs will probably survive stress which would result in the extinction of populations with low CVs. Mass of mycorrhizal plants of both species decreased more rapidly with increasing density than did non-mycorrhizal plant mass. It is concluded that the cost of being mycorrhizal increases as plant density increases, while the benefit decreases. The results suggest that mycorrhizas will influence density-dependent population processes of faculative and obligate mycorrhizal species. Springer-Verlag, 1992 Vesicular-arbuscular mycorrhizas nationallicence Densitydependence nationallicence Plant population dynamics nationallicence Resource depletion nationallicence Phosphorus nationallicence Allsopp N. Department of Botany, University of Cape Town, Private Bag, 7700, Rondebosch, South Africa aut Stock W. Department of Botany, University of Cape Town, Private Bag, 7700, Rondebosch, South Africa aut Oecologia Springer-Verlag 91/2(1992-08-01), 281-287 0029-8549 91:2<281 1992 91 442 https://doi.org/10.1007/BF00317797 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00317797 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Allsopp N. Department of Botany, University of Cape Town, Private Bag, 7700, Rondebosch, South Africa aut NATIONALLICENCE 700 1- Stock W. Department of Botany, University of Cape Town, Private Bag, 7700, Rondebosch, South Africa aut NATIONALLICENCE 773 0- Oecologia Springer-Verlag 91/2(1992-08-01), 281-287 0029-8549 91:2<281 1992 91 442 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer