Vesicular-Arbuscular Endomycorrhizal Colonization of Wetland Plants

Abstract

Mycorrhizal fungi colonize many terrestrial plants and often result in an increased uptake of P and several micronutrients. Little information is available on the relationships among vesicular-arbuscular endomycorrhizae (YAM), aquatic plants, and plant P concentrations. The major objectives of this study were to measure the degree of YAM colonization of wetland plants, and to determine the relationship between colonization and plant P concentrations when sampled from two contrasting water regimes (hydric soil with no surface water and hydric soil with a minimum of 10 cm of surface water). Two semipermanent wetlands in Lake County, South Dakota, were chosen for the study. Water regime did not have a significant effect on total or organic soil P concentration. Vesicular-arbuscular endomycorrhizal spore samples collected from wet soils averaged 5000 spores kg"' compared with 2740 spores kg"' in dry soils. The eight plant species evaluated to determine VAM colonization were reed canarygrass (Phalaris arundinacea L.), slough sedge (Carex atherodes Spreng.), river bulrush [Scirpus fluviatilis (Torr.) Gray], slender rush (Juncus tenuis Willd.), dogbane (Apocynum cannabinum L.), water smartweed (Polygonum amphibium L.), cattail (Typha Xglauca Godr.), and wild licorice (Glycyrrhiza lepidota (Nutt.) Pursh). Vescular-arbuscular endomycorrhizal colonization ranged from 78% (wild licorice) to none (slough sedge and slender rush). Roots from dry areas averaged 27% colonization compared with less than 1% in wet areas. Colonization levels of dogbane and reed canarygrass in dry zones were highly correlated to plant P concentrations. The results of this study indicate that several wetland plant species develop substantial mycorrhizal associations, particularly in relatively dry environments.

Seasonal Diversity of Arbuscular Mycorrhizal Fungi in Mangroves of Goa, India

“…Some reports suggest that AM fungi are obligately aerobic, �ooding reduces sporulation [35], and total spore density correlates negatively with soil moisture [36]. Others have found higher values of total spore density in wet soils than in dry soils [37] and have suggested that high sporulation is a stress response to adverse or extreme environmental conditions.…”

Diversity and function of fungi in peatlands: A carbon cycling perspective

“…& Gerd. ) Anderson et al 1984;Rickerl et al 1994;Wetzel and van der Valk 1996;Cooke and Lefor 1998), with the former genus appearing to be the dominant one.…”

Arbuscular mycorrhizal colonization of semi‐aquatic grasses along a wide hydrologic gradient

“…Anderson et al, 1984 ;Rickerl et al, 1994 ;Stevens & Peterson, 1996), although the reason for this is unclear. If available soil oxygen is important to the survival of AM fungi, factors regulating colonization in wetlands will also include the soil redox potential and plant morphological features regulating oxygen diffusion into the root zone and loss to the rhizosphere.…”

“…Flooding has been correlated with both higher (Rickerl et al, 1994) and lower (Anderson et al, 1984 ;Khan, 1993a,b) numbers of AM fungal spores along a wetland gradient. Although patterns of spore abundance provide useful information on prior C allocation to fungi, it is hard to predict how the presence of spores affects the inoculum potential of wet soil.…”