Research was conducted to determine the effect of salinity on Rhizobium and growth of dry bean.
A commercial cultivar (Akman 98) of dry bean (Phaseolus vulgaris L.) was inoculated with Rhizobium
tropici strain CIAT899 and native Rhizobium in solution culture with different salt concentrations (control,
5, 10, 20 and 40 mmol1
) added before inoculation. The results indicated that population of R. tropici
strain CIAT899 and natural Rhizobium were decreased with salinity levels. However, the population count
train CIAT899 was inversely proportional to salt concentration with high growth (8.0e9.0 105 cfu ml1
)
at lower concentrations of control e 5 mmol1 and low growth (4.0e6.0 105 cfu ml1
) at higher salt
concentrations of 20 mmol1
. The plant root and shoot dry weight, chlorophyll content, plant height, root
length, total nitrogen, symbiotic efficient and efficient rate were affected by salt stress in tested plant and
both inoculations. Total nitrogen content decreased significantly at the highest level of salinity. It is
important to decrease the soil salinity and to improve the yield of dry bean (P. vulgaris L.) as well as the
Rhizobium sp. associated with it.