IMPLICATIONS U9 



IMPLICATIONS 



Experiments involving the maintenance of fungi in culture at 

 a given constant temperature for considerable periods have a 

 limited usefulness. This conclusion finds support in the fact that 

 in nature fungi do not encounter constant temperature. Experi- 

 ments with controlled temperature have demonstrated, it appears, 

 that optimal temperature requirements exist for each metabolic 

 activity of a given fungus and for each phase in its developmental 

 cycle. It is desirable therefore that a much larger body of data 

 showing these facts be accumulated, for from such experiments 

 would certainly come increased understanding of temperature as 

 an environmental factor in fungus activities. 



Some persons are inclined to make light of the popular idea that 

 "diseases are caused by weather." Indeed, such persons may with 

 fairness be accused of overemphasizing the "germ theory." They 

 are content to stress the primary cause of disease and to overlook 

 secondary or attendant causes. Since temperature is one of the 

 components of weather, it cannot be ignored in its influence, 

 among pathogenic fungi, upon such sequential phenomena as 

 spore dispersal, spore germination, incubation and severity of the 

 resultant disease, and, finally, the development of reproductive 

 elements by the pathogen. 



LITERATURE CITED 



Ames, A., "The temperature relations of some fungi causing storage rots," 



Phytopathology, 5: 11-19, 1915. 

 Bartetzko, H., "Untersuchungen iiber das Erfrieren von Schimmelpilzen," 



Jahrb. iviss. Botan., 41: 57-98, 1910. 

 Becquerel, P., "Recherches experimentales sur la vie latente des spores des 



Mucorinees et des Ascomycetes," Conip. rend., 150: 1437-1439, 1910. 

 Bennett, F. T., "Gibberella saubinettii (Mont.) Sacc. on British cereals. II. 



Physiological and pathological studies," Ann. Applied Biol., 18: 158-177, 



1931. 

 Bisby, G. R., "Zonation in cultures of Fusarhmi discolor sulphureum," 



My col., 11: 89-97, 1925. 

 Blackman, F. F., "Optima and limiting factors," Ann. Botany, 19: 281-295, 



1905. 

 Brooks, Charles, and J. S. Cooley, "Temperature relations of apple-rot 



fungi," /. Agr. Research, 8: 139-164, 1917. 



