Defoliation effects on arbuscular mycorrhizae and plant growth of two native bunchgrasses and an invasive forb [An article from: Applied Soil Ecology]

This digital document is a journal article from Applied Soil Ecology, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Centaurea maculosa, an invasive forb in western North American grasslands, dominates more than 4millionha of rangeland in the Rocky Mountain region. Our research examined the effects of herbivory and arbuscular mycorrhizae (AM) on the growth of C. maculosa, and two native grasses, Festuca idahoensis and Pseudoroegneria spicata. Plants were grown for 11 weeks, with or without AM, prior to simulated herbivory. We removed 75% of aboveground biomass from half of the plants, and harvested all plants 4 weeks later. All species increased their growth rate after clipping, but clipped plants were smaller than unclipped plants. The difference in biomass between clipped and unclipped plants was smaller for C. maculosa (clipped:unclipped=0.62) than for the native grasses (0.42 and 0.52). Plants with AM were smaller than non-AM plants across all species, with the greatest reduction in F. idahoensis (77% versus 18% in C. maculosa and P. spicata). Levels of AM colonization were minimal in F. idahoensis (