In 2013 Sharma and his coworker (6) pointed that the naturally occurring soil rhizobia
nodulating legumes plants lived in the desert areas are expected to have higher tolerance to common adverse conditions such as salt stress.
The two groups of rhizobia
strains have a strong significant (G1: P < 0.001, G2: P < 0.05) inverse correlations (G1: r = -0.8, G2: r = -0.7) were observed between the pH of the cultures and their soluble P content.
(2013), these effects promoted by co-inoculation with PGPB and rhizobia
seem to be influenced by specific signals between the involve bacterial genotypes and the plant host genotype.
Given that rhizobia
are taxonomically diverse , efficient methods of classifying isolates are necessary to identify strains with high nitrogen-fixation ability .
The production of EPS is specific to rhizobia
, which gives a viscosity to bacterial colonies when they are cultivated on a solid medium .
Several studies have reported an increase in the yield of grass species due to inoculation with rhizobia
, even if these bacteria are not able to fix N in association with grasses (Yanni et al., 2001; Mishra et al., 2006; Hahn, 2013; Machado et al., 2013; Osorio Filho et al., 2014).
(2014) used Cratylia argentea for recovery of degraded areas in the cerrado, and only one individual in the field was associated with native rhizobia
. These previous studies strengthen the relevance of the current research.
However, this ability is genotype-dependent because the climate may affect directly the non-native rhizobia
and restrict the survival and efficiency of the root set in nodulating plants.
Intercropping of Sesbania (Sesbania sesban) and leucaena (Leucaena leucocephala) with five annual grasses under semi-arid conditions as affected by inoculation with specific rhizobia
and associative diazotrophs.
have been sent as far as space, when strains were supplied to the Kennedy Space Center for nitrogen fixation studies on the space shuttle.
After four years there may be more response to inoculation because lower numbers of rhizobia
will remain in the soil, so a soil top layer with the potent commercial inoculation strain may be more beneficial.