In Vitro Growth and Nutrition of Buergenerula Spartinae, a Fungus Associated with Spartina Alterniflora

SUMMARY

The Ascomycete Buergenerula spartirne, occurs commonly on the leaves and culms of salt marsh cordgrass, Spartina alterniflora, and appears to be limited to this host in the USA. This fungus can be observed on the growing, senescing, and dead stages of the plant and appears to invade initially as a weak parasite. Laboratory studies were conducted on the effects of environmental and nutritional factors on growth of Buergenerula spartirne. Growth of the fungus increased with increasing salinity to 30%c and 30 C was the optimum temperature. The dry matter produced by the fungus decreased with increasing concentrations of mannitol and polyethylene glycol indicating that the growth response was due to an ionic rather than an osmotic effect with seawater. Greater mycelium production occurred in standing versus shake culture and when cultures were exposed to light. All of the 12 carbohydrates tested were utilized except galactose and mannitol. Ammonium salts were the most readily utilized nitrogen sources, followed by amino acids, and NaNO₃. Growth was greatest at C:N ratios of 5:1 to 20:1. Thiamine, biotin, and pyridoxine were required and growth was reduced when iron and zinc were deleted from the culture medium.