Chemotaxonomic and ultrastructural studies on three species of Tilletia occurring on wheat

Abstract

Electron microscopic investigations and chemical analyses were made on the spores of three species of Tilletia. Frozen-etched preparations examined in the electron microscope revealed that the spore walls of both T. foetida (smooth external surface) and T. caries (reticulate surface with some hair-like projections) contain two layers. The spore wall of T. controversa (complex reticulate surface with many hair-like projections) contains three layers. The outer layer in T. controversa has granular regions which form a reticulated pattern on the surface. The hydrocarbon content of the three Tilletia species was essentially the same. The compounds in benzene and the methanol (free fatty acids) fractions gave distinct gas chromatographic patterns for each of the three species. T. foetida was the highest in saturated fatty acids with T. controversa second followed by T. caries. The reverse situation existed with respect to the unsaturated fatty acids.

Lipids of Rhizopus arrhizus Fischer

“…Distribution of the total fatty acids in the sporangiospores and mycelia of R. arrhizus shows many similarities. The high concentrations of linoleic acid are consistent with the results of spore analysis of several fungal organisms previously analyzed (5,7,17). The low concentrations of linolenic acid are also consistent with spores previously analyzed (5,17).…”

“…The high concentrations of linoleic acid are consistent with the results of spore analysis of several fungal organisms previously analyzed (5,7,17). The low concentrations of linolenic acid are also consistent with spores previously analyzed (5,17). These consistencies remain true even though environmental conditions are different for the mycelia and spore cultures.…”

“…It was not detected in sporangiospores grown under similar conditions. The accumulation of squalene in such high concentrations in mycelia seems unusual; however, the lack of this compound in sporangiospores is consistent with hydrocarbon analyses of other fungal spores in our laboratory (2,(5)(6)(7)16). Investigations are now underway in our laboratory to determine the relationship of the accumulation of squalene to sterol synthesis and various physiological processes such as sporulation.…”

Ultrastructure of lipid bodies in Tilletia caries teliospores

“…Although temperature may be controlled within spores, the microenvironment inside is very complex. For example, T. caries teliospores contain a broad range of lipids and seven major free fatty acids, with significant variation in carbon chain length and degree of saturation (11). The presence of water and other cytoplasmic factors also influences the liquid environment.…”

Organics associated with the outer surface of airborne urediospores

“…Preliminary studies by Oró et al (1966) of the spore lipids extracted from the surface of several smut fungi have shown that alkanes, free fatty acids, and fatty acid methyl esters are common. Recent evidence (Laseter, Hess et al, 1968) has suggested that ketones and aromatics may also occur.…”