Although Azospirillum spp. are considered to be important plant growth promoting bacteria, their possible effects on germination and vigor of aged lettuce seeds has not been previously evaluated. In fact, there is a paucity of published data about inoculation effects on seed germination. The aim of this work was to evaluate seed quality of oneyear aged lettuce (Lactuca sativa L. cv. Crimor INTA...

The effects of soil moisture on the survival of three diazotrophic bacteria species (Azospirillum amazonense, Gluconacetobacter diazotrophicus and Azospirillum brasilense) were tested. Soil moisture had little influence on the survival of A. brasilense, which is considered a free-living species. On the other hand, increased soil moisture extended the survival of the endophytes A. amazonense and...

Batch and fed batch cultures of Azospirillum brasilense Sp245 were conducted in a bioreactor. Growth response, IAA biosynthesis and the expression of the ipdC gene were monitored in relation to the environmental conditions (temperature, availability of a carbon source and aeration). A. brasilense can grow and produce IAA in batch cultures between 20 and 38 degrees C in a standard minimal medium...

Restriction analysis of amplified 16S rDNA from bacterial strains isolated from soil was used to evaluate the effects of swine manure and urea fertilisation on indigenous populations of the plant growth promoting bacterium, Azospirillum brasilense, in corncultivated experimental plots. Several operational taxonomic units (OTUs) were found among the isolates. One of them, identified as A. brasil...

The survival of Azospirillum brasilense Cd and Sp-245 in the rhizosphere of wheat and tomato plants and in 23 types of plant-free sterilized soils obtained from a wide range of environments in Israel and Mexico was evaluated. Large numbers of A. brasilense cells were detected in all the rhizospheres tested, regardless of soil type, bacterial strain, the origin of the soil, or the amount of rain...

The effects of 10, 50, 100, 200 and 300 ìg mlÿ1 of bromopropylate and methidathion were investigated in the cells of Azospirillum brasilense grown in chemically de®ned media and dialysed-soil media. The insecticide bromopropylate did not affect microbial growth, the levels of ATP and dinitrogen ®xation of A. brasilense in either chemically de®ned media or dialysedsoil media. Methidathion signi®...

Co-aggregation was attempted in Azorhizobium caulinodans ORS-571 with other agriculturally important microorganisms such as Azospirillum brasilense MTCC-125, Azotobacter chroococcum MTCC-446, Bacillus megatherium MTCC-3353, and Pseudomonas fl uorescens MTCC-4828 to develop coaggregates with multiple benefi ts using seed powders of diff erent plants viz., Moringa oleifera, Strychnos potatorum an...

Ever since the discovery of the role of bacteriophytochrome (BphP) in inducing carotenoid synthesis in Deinococcus radiodurans in response to light the role of BphPs in other non-photosynthetic bacteria is not clear yet. Azospirillum brasilense, a non-photosynthetic rhizobacterium, harbours a pair of BphPs out of which AbBphP1 is a homolog of AtBphP1 of Agrobacterium tumefaciens. By overexpress...

Ammonium chloride (greater than or equal to 0.05 mM) effectively and reversibly inhibited the nitrogenase activity of Azospirillum brasilense, Azospirillum lipoferum and Azospirillum amazonense. The glutamine synthetase inhibitor L-methionine-DL- sulfoximine abolished this "switch-off" in A. lipoferum and A. brasilense, but not in A. amazonense. Azaserine, an inhibitor of glutamate synthase, in...

The lon gene of Escherichia coli encodes the lon (La) protease, which is associated with cellular protein degradation. A lon gene homolog from Azospirillum brasilense, a nitrogen-fixing soil bacterium which lives in association with the roots of cereal grasses, was cloned and characterized. The nucleotide sequence of the A. brasilense lon gene was determined. It contains an open reading frame t...