Arbuscular mycorrhizae are important for growth and survival of tropical trees. We studied the community of arbuscular mycorrhizal fungi in a tropical mountain rain forest and in neighbouring reforestation plots in the area of Reserva Biológica San Francisco (South Ecuador). The arbuscular mycorrhizal fungi were analysed with molecular methods sequencing part of the 18 S rDNA. The sequences wer...

The symbiotic association between certain plants and microorganisms plays an important role in soil fertilization, and improves their growth and mineral nutrition. Microorganisms implicated in this symbiotic interaction are from two groups: bacteria and fungi. The bacteria group is implicated on nitrogen fixation (for review see Pawlowski and Bisseling, 1996), while the fungal group is involved...

Mycorrhizal fungi constitute a key functional group of soil biota that greatly contribute to productivity and sustainability of terrestrial ecosystems. These are ubiquitous components of most of the ecosystems throughout the world and are considered key ecological factors in governing the cycles of major plant nutrients and in sustaining the vegetation cover (van der Hejden eta!. 1998; Requena ...

In surveys in the Hawaiian Islands, mycorrhizae occurred frequently in epiphytic, nonorchidaceous angiosperms and pteridophytes. Both vesicular-arbuscular (VA) and ericoid mycorrhizae were present in epiphytes growing 1-3 m above the forest floor on dead and living tree trunks and on living tree ferns in montane wet forest sites. All eight angiosperm species were mycorrhizal, and 13 of 22 pteri...

Phosphorus-32 applied to leaves of Plantago erecta in a serpentine annual grassland reached the shoots of about 20 percent of the close neighbors. Vesicular-arbuscular mycorrhizae connect the root systems of neighbors of different species and probably mediate nutrient transfers among them. Spatial patterns of transfer show that taxonomic affinity, distance from donor, and size of recipient do n...

The mycorrhizal status of dune plants from the island of Hawaii was investigated. All plants, including Batis maritima, Cocos nucifer, Ipomoea brasiliensis, Pennisetum setaceum , Prosopis pallida, Scaevola taccada, and Sporobolus sp., had vesicular urbuscular mycorrhizae (VAM) . Levels of colonization by VAM fungi ranged from less than 10% to 100% of the root length and were highest in Ipomoea ...

The ancient arbuscular mycorrhizal association between the vast majority of plants and the fungal phylum Glomeromycota is a dominant nutritional mutualism worldwide. In the mycorrhizal mutualism, plants exchange photosynthesized carbohydrates for mineral nutrients acquired by fungi from the soil. This widespread cooperative arrangement is broken by 'cheater' plant species that lack the ability ...

Subterranean clover inoculated or not with the arbuscular mycorrhizal (AM) fungus Glomus intraradices was grown on soil containing six levels of 238U in the range 0-87 mg kg(-1). Increasing U concentration in soil enhanced the U concentration in roots and shoots of both mycorrhizal and nonmycorrhizal plants but had no significant effects on plant dry matter production or root AM colonization. M...