Germination and germ tube growth of the arbuscular mycorrhizal fungi Gigaspora albida in different substrates

Abstract

The role of the substrate on germination of Gigaspora albida Schenck & Smith was investigated. Spores were desinfested with 0.5% sodium hypochlorite (20 min.) and placed on Petri dishes over a Millipore filter, with one of the following media: a-1% water-agar; b-water-agar + aqueous extract of roots of Panicum miliaceum L.; c-salt medium of Murashige & Skoog (MS) or sterilized sand; and incubated in the dark at room temperature (28ºC ± 2). The experimental design was at random with four treatments and four replicates. Germination was evaluated every 7 days until the 28 th day. The water-agar medium was the most feasible for spore germination at the 7 th day, followed by the MS medium at the 14 th day. Conversely, the sand and the root extract medium did not allow high germination. Spores maintained in water-agar also presented longer germ tubes than spores in the other treatments. Auxiliary cells were observed at the beginning of formation of hyphal branching in all treatments, however they were more numerous in the water-agar medium.

Effect of Sterilization on Arbuscular Mycorrhizal Fungal Activity and Soil Nutrient Status

“…Spores were isolated from 50 g treated AM fungus inoculum by the wet sieving and decanting method (Gerdemann and Nicolson 1963). The germination rate of spores was measured by method described in earlier study (Maia and Yano-Melo 2001). The viability of spores was measured by using tetrazolium salts as vital stains (Walley and Germida 1995), briefly, using the tetrazolium salt Fig.…”

Life History Strategies in Gigasporaceae: Insight from Monoxenic Culture

“…Spore germination does not require external factors other than humidity and temperature to germinate. Germination rates reached a 80-100% level for Gigaspora isolates (Koske 1981b;Bécard and Piché 1989a;Diop et al 1992;Romero and Siqueira 1996;Maia and Yano-Melo 2001), compared to 60% for Scutellospora (de Souza, unpubl. data).…”

Ciências biológicas: as diversas manifestações da vida

“…Germination of AMF spores occurs simply by the presence of water (Harrison, 2005), but, spore germination is influenced by the need for a period of dormancy; soil moisture; temperature; pH (Daniels, and Trappe, 1980;Maia and Iano Melo , 2001); light; CO2 levels and presence of bacteria (Xavier, and Germida, 2003;Chen et al, 2008). However, the most responsive variables are root exudates.…”