Ahmad, Mohammed, H.; Morgan, V.
Author Affiliation, Ana.
Characterization of a cowpea (Vigna unguiculata) rhizobiophage and its effect on cowpea nodulation and growth
Biology and Fertility of Soils
Date of Publication
A cowpea rhizobiophage (JRW3 phage) from Jamaican soil was isolated and characterized. The phage has a polyhedral head and a non-contractile tail; maximum adsorption of the phage to the host occured after 5 min. A one-step growth experiment revealed that the latent period, rise period and burst size of JRW3 phage were 12h, 16h, and 28 plaque-forming units/cell, respectively. The JRW3 phage was highly sensitive to heat, but survived well between ph 5 and 8. The phage was stable in EDTA, though completely inactivated in sodium citrate. Host range analysis showed that 7 of the 40 Rhizobium and Bradyrhizobium strains tested were sensitive to phage infection. The phage significantly reduced nodule numbers and shoot dry weight of cowpea plants when inoculated with rhizobia in combination with the phage.....