A Procedure for Isolation of Single‐spore Cultures of Certain Endomycorrhizal Fungi

Abstract

SUMMARY.\ procedure for the isolation of single-spore cultures of endomycorrhizal fungi is described. A single spore is placed on plant roots with a Pasteur pipette by use of a binocular microscope, and the plant is transplanted into sand in a 50 ml growth tube. Plants are incubated for 6 to 8 weeks in a greenhouse and are continuously subirrigated by capillarity with dilute (5 to 10%) Hoagland's solution. Forty to 80 °o of plants inoculated by this technique with single spores of Gtomus macrocarpus, G. etunicatus and G. caledonius became infected. Cultures of G. constrictus and G. microcarpus were not obtained. Hoagland's solutions of up to 25°,, were equally effective for isolating G. macrocarpus, but limiting plant size by using only 5 or 10% Hoagland's solution was advantageous. The presence of spores on living root systems was the most reliable indicator of fungal development. Non-inoculated control plants incubated in a common Hoagiand's solution reserv^oir with inoculated plants never became mycorrhizal. The procedure uses readily available materials, is easy to use in the laboratory-and conserves greenhouse space and labour.

Characterization and pathogenicity of six Cytospora strains causing stem canker of wild apple in the Tianshan Forest, China

“…The structure of conidiomata, presence or absence of a conceptacle, and the size and shape of spores were recorded using an anatomical microscope (Olympus, SZX10–3141). Single spores were isolated following the protocol described by Fang, Mcgraw, Modjo, and Hendrix (2010). Parts of the hymenia containing three or four sporocarps of fresh material were cut horizontally and vertically with a sterile scalpel and then crushed in a drop of sterile water on a glass slide.…”

“…The structure of conidiomata, presence or absence of a conceptacle, and the size and shape of spores were recorded using an anatomical microscope (Olympus, SZX10-3141). Single spores were isolated following the protocol described by Fang, Mcgraw, Modjo, and Hendrix (2010).…”

A simple and inexpensive method for producing and maintaining closed pot cultures of arbuscular mycorrhizal fungi

“…113 SA, GmbH, Solingen, Germany), directly on a root. Accurate placement was assured by use of a dissecting microscope as recommended by Fang et al (1983). The excavation was then carefully filled in, the plant watered gently with sterile distilled water from a laboratory wash-bottle, and the pots placed in the Sunbags which were then sealed as described above.…”

“…Further modifications of the system will be necessary to establish optimum conditions for particular species, but it is likely that, given the correct plantfungus combination and appropriate substrate, nutrient regime, moisture, light, and temperature conditions to optimise the growth of these symbionts, the system could be adapted to provide controlled maintenance and production of any arbuscular mycorrhizal fungus. Critical study of arbuscular mycorrhizal fungi requires their production under controlled microbiological conditions Mosse (1962) and the production of single spore cultures ofarbuscular mycorrhizal fungi is the best option to investigate the extent of their genetic variability and diversity (Fang et al 1983). However, the integrity of such ramets (Walker 1993) cannot be guaranteed in open pot cultures.…”