Interrelation of growth media and water activity in sclerotia characteristics of Aspergillus section Flavi.
OBJECTIVE
To examine sclerotium characteristics of two Aspergillus flavus and two A. parasiticus strains at different growth media and water stress.


RESULTS
The effects of growth media and water activity (0.999, 0.971, 0.955 and 0.937) on characteristics of sclerotia production (number, size and volume) of four isolates of Aspergillus section Flavi were examined. There was total inhibition under the driest conditions (0.955 and 0.937). When an osmotic potential of 0.971 was generated in Czapek agar (CD) and maize meal extract agar with sucrose and sodium nitrate (MMEA S/N), an increase in sclerotial size and volume was observed. The amount of sclerotia produced by cultures at 0.999 a(w) value was higher on CD.


CONCLUSIONS
The data show that the sclerotia characteristics of A. flavus and A. parasiticus have been influenced by water availability and growth media composition.


CONCLUSIONS
The information obtained shows that if we know the nutritional and water stress requirements for sclerotia production, it could be possible to develop effective prevention strategies to inhibit the survival of these fungi in grain.
Nesci
A
A
Orientación Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.
Morales
M
M
Etcheverry
M
M
D001231:Aspergillus flavus / Q000254:growth & development*; D003470:Culture Media; D014867:Water
D003470:Culture Media; D014867:Water