Studies on Physiology of Some Plant Pathogenic Bacteria 
CONCLUSION 
Agar or gelatin media, if cooled before being made acid or alkaline will jellify 
at limits far beyond pH concentrations tolerated by microorganisms. They may 
be manipulated so as to avoid contamination during adjustment of reaction 
and need not be subsequently sterilized. 
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ties of agar-agar. Jour. Indus, Eng. Chem. 8, 1128-1132. 
Fred, E. B. and Davenport, Audrey, 1918. Influence of reaction on nitro¬ 
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