Publication Date
1985
Location
Kyoto Japan
Description
The production of large quantities of ascospores of Sclerotinia trifoliorum is possible in the laboratory. The sclerotia of the fungus are obtained on autoclaved potato slices after 1 month growth at 20°C, in the darkness. After that time, sclerotia are placed during 1 month at 30°C in order to remove their dormancy, then slightly hurried in humid vermiculite at 15°C, under fluorescent light. The first apothecia appear 1 month later, the production lasts for 2 months. The average yield is 2 x 103 to 4 x 103 apothecia for 104 sclerotia. Every apothecium produces an average of 3 x 104 ascospores. Ascospores are used as inoculum for testing red clover resistance to crown rot in a growth chamber. The results are well correlated with field observations. Ascospores are also used for screening fungicides after plant inoculation. The best fungicides tested are benomyl, carbendazime and iprodione. Inoculations are realized in a growth chamber at 15-17°C and R.H. 100 % by spraying 2 to 3 months old plants with an aqueous suspension of ascospores (104 to 5 x 104 spores/ml), added with glucose (10 g/1) and a wetting agent (Tween 20). An important short-term objective is the use of ascospores for screening on a large scale resistant plants in growth chambers for selection programs.
Citation
Raynal, G and Picard, J, "Laboratory Production of the Sexual Stage of Sclerotinia trifoliorum, The Winter Crown-Rot Agent of Red Clover Consequences for Improving Control Methods" (1985). IGC Proceedings (1985-2023). 6.
(URL: https://uknowledge.uky.edu/igc/1985/ses7/6)
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Laboratory Production of the Sexual Stage of Sclerotinia trifoliorum, The Winter Crown-Rot Agent of Red Clover Consequences for Improving Control Methods
Kyoto Japan
The production of large quantities of ascospores of Sclerotinia trifoliorum is possible in the laboratory. The sclerotia of the fungus are obtained on autoclaved potato slices after 1 month growth at 20°C, in the darkness. After that time, sclerotia are placed during 1 month at 30°C in order to remove their dormancy, then slightly hurried in humid vermiculite at 15°C, under fluorescent light. The first apothecia appear 1 month later, the production lasts for 2 months. The average yield is 2 x 103 to 4 x 103 apothecia for 104 sclerotia. Every apothecium produces an average of 3 x 104 ascospores. Ascospores are used as inoculum for testing red clover resistance to crown rot in a growth chamber. The results are well correlated with field observations. Ascospores are also used for screening fungicides after plant inoculation. The best fungicides tested are benomyl, carbendazime and iprodione. Inoculations are realized in a growth chamber at 15-17°C and R.H. 100 % by spraying 2 to 3 months old plants with an aqueous suspension of ascospores (104 to 5 x 104 spores/ml), added with glucose (10 g/1) and a wetting agent (Tween 20). An important short-term objective is the use of ascospores for screening on a large scale resistant plants in growth chambers for selection programs.
