Feeback between Plants and Their Soil Communities in an Old Field Community

Abstract

The nature of the interaction between plants and their soil community was investigated by testing for differential responses of four old-field perennial plant species to inocula derived from soil communities that had been grown with ("cultured by") one of these four plant species. The differentiation of the soil communities was evident in measurements of plant survival, phenology, growth, and root-shoot ratios. Effects on survival and growth suggest negative feedbacks between these species and the soil communities that they culture. Survival rates of Krigia dandelion were significantly reduced when grown with their "own" soil community. Considered as a whole, the three other species (all grasses) had significantly lower growth and root-shoot ratios when grown with soil communities started with their own inocula compared to soil communities started with the inocula of other species. However, the significance of this effect on growth rate and root-shoot ratios was due primarily to the pairwise comparison of Anthoxanthum odoratum and Danthonia spicata and of Anthoxanthum and Panicum sphaerocarpon, respectively. Pairwise comparisons of Danthonia and Panicum do not suggest differential responses to each other's soils in growth rate or root-shoot ratios nor do soil communities appear to affect the relative competitive ability of these two species. While the components of the soil community responsible for these effects have not been identified, similar although less pronounced patterns were observed in experiments using inocula consisting of washed live root segments as compared to experiments using whole soil as inoculum, suggesting that root pathogens are one important agent.

Negative feedback within a mutualism: host–specific growth of mycorrhizal fungi reduces plant benefit

“…Conversely, a high abundance of Panicum would be predicted to have an indirect bene cial effect on the growth of Plantago through the changes in the AM fungal community. To my knowledge, this is the rst demonstration of negative feedback being generated within a mutualism, and this result adds credence to previous observations indicating similar dynamics ( Johnson et al 1991;Bever 1994;Kiers et al 2000;Bever et al 2002).…”

Funcionalidad de hongos micorrízicos arbusculares en tres comunidades vegetales de la Reserva Florística Manejada de San Ubaldo-Sabanalamar, Cuba

“…The highest density of AMF spores observed in the dry period in our study is consistent with other reports (Guadarrama, & Álvarez-Sán-chez, 1999;Lugo, & Cabello, 2002;Cuenca, & Lovera, 2010). Bever (1994) also found that in tropical ecosystems, rains favor AMF spores germination, thereby decreasing their presence in soil during wetter seasons. The results of the brief taxonomic determination indicate no differences between AMF diversity among the tested environments.…”

The extent of mycorrhizal colonization of roots and its influence on plant growth and phosphorus content

“…Instead, it is possible that standing root length increased concurrently with AMF abundance, which could occur if plants grew more fine roots upon colonization by AMF. Second, although AMF can negatively affect the growth of host plants under certain conditions (Bever 1994;Bever et al 1997;Johnson et al 1997;Klironomos 2002;Castelli and Casper 2003;Hart et al 2003;Klironomos 2003;Jones and Smith 2004;Smith 2011b, 2012), these situations were rare within this meta-analysis. In fact, a reduction in plant growth in response to increases in PRLC (i.e., a response ratio <1.0) was recorded in only 18 of the 195 trials surveyed here (Online Resource 1).…”