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Water
relations of Pseudomonas solanacearum
N.T. Mazomba* and L.V. Mabinya
Department of Biochemistry and Microbiology, School of
Biological and Environmental Sciences, University of Fort
Hare, Alice, 5700, South Africa.
*Corresponding author. E-mail:
nmazomba@ufh.ac.za.
Abbreviations: GYS,
d-Glucose-YS;
aw, water activity.
Accepted 15 April, 2010 |
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The growth of 16 strains of Pseudomonas solanacearum at
different water activities was investigated. These studies
were undertaken in order to understand the adaptive
mechanisms to osmotic stress of bacteria colonizing plants
and to elucidate bacterial persistence when the efforts to
eradicate disease fail. Due to inadequate growth of some
strains on GYS medium, 3 strains, 66, 64 and 46, were
selected for further investigation. These strains showed
varied growth patterns on growth media at different water
activities, with strain 66 showing the highest tolerance at
very low water activity, that is, at 0.970, than the other
two strains. The variation observed in the osmotolerance of
the strains is an indication of the subtle differences among
the strains of the same species.
Key words:
Pseudomonas solanacearum, water activity, osmotolerance,
osmotic stress. |
