Table 1.

Qualitative response of bacteria towards exopolysaccharide (EPS) assay

Bacterial strain	Response at pH 5.5			Response at pH 7.5
	28 °C ± 2	37 °C	45 °C	28 °C ± 2	37 °C	45 °C
R1	+	+	–	+	++	–
R2	+	++	+	+	++	++
R3	+	++	+	+	++	++
R4	+	++	–	+	++	++
R5	ND	++	+	ND	+	++

Legend: + = positive, - = negative, + + = strongly positive, ND =Not determined, R1= Rhizobium sp. strain R1, R2 = Rhizobium tropici strain R2, R3 = Rhizobium cellulosilyticum strain R3, R4 = Rhizobium taibaishanense strain R4 and R5 = Ensifer meliloti strain R5