A greenhouse bioassay was used to investigate effects of natural and manmade disturbances on native ectomycorrhizal populations of Douglas-fir and western hemlock on a steep southeast slope in the
west central Cascade Mountains. Total and mycorrhizal root tips were counted on seedlings grown in soils collected from (a) two 100+...
Field and greenhouse bioassays were used to compare the mycorrhizal associations of Douglas-fir seedlings from undisturbed forests, and nonburned and burned portions of clearcuts on three Sites in the west-central Cascades of Oregon. Field soil transfers and greenhouse soil pasteurization and reinoculation were used to investigate soil biology and inoculum...
Basidiospores of Rhizopogon viriicolor Smith and R. colossus
Smith were inoculated onto container-grown Douglas-fir (Pseudotsuga
menziesii (Mirb.) Franco) seedlings and grown under two levels of
soluble fertilizer and one level of slow-release fertilizer. Both
fungi formed abundant (54%) ectomycorrhizae under the soluble
fertilizer regimes. Slow-release fertilizer greatly reduced percent
ectomycorrhizae...
The several thousand fungi known to form ectomycorrhizae have co-evolved with their host plants and have developed impressive physiological and ecological diversity. Exploration of some relationships of enzyme activities and phytohormone production of selected ectomycorrhizal fungi to distribution and tree hosts is reported in this thesis. The data have particular...
Many higher plants have mycorrhizae associated with their roots. These structures are often essential for survival and growth (Harley & Smith 1983). Mycorrhizae are known for the abilities to enhance nutrient absorption. While nitrogen-fixing organisms are found as components of the mycorrhizosphere, mycorrhizal fungi are not presently known to fix...
A greenhouse bioassay was used to compare the effects
of soils collected at different distances from hardwood
species on the growth, mycorrhiza formation, and foliar
nutrient concentrations of Douglas-fir seedlings. Soil
nutrient concentrations and bulk densities were also
determined. Soils were collected from two southwestern
Oregon sites that had been...
Miombo woodland and dambo grassland soils were selected to study the effect of soil transfer on early growth of B. petersiana, C. spectabilis, and C. calothyrsus on degraded sites in northern Zambia. The experiment was conducted on previously slash and burned, cultivated, and abandoned sites. Both sterile and unsterile miombo...
Mycorrhizae are important for plant growth, particularly in nutritionally poor soils. Vesicular-arbuscular mycorrhizae (VAM) are the primary form of mycorrhizae found in tropical plants, and their persistence in the soil as colonizing fungal propagules following deforestation cannot be directly
measured. Utilizing the "most probable number" (MPN) method for estimating infective...
A grassland restoration project was conducted in Canyonlands National Park on an area recently disturbed due to construction. Two native grasses (Oryzopsis hymenoides and
Stipa comata) were seeded with 18 different soil treatments. Stipa density and relative mycorrhizal colonization were measured. None of the soil treatments resulted in significantly greater...
A Study conducted at The Island, Lake Billy Chinook, in Central Oregon, examined
differences in the pattern of soil properties between a sagebrush-grass and a juniper-sagebrush-grass community. Juniper invasion is linked with the desertification
process in which the sagebrush shrubs and perennial grasses decline. Patterns in soil
nutrients and other...