Thiosulfate oxidizing bacteria isolated from crop plants were tested for their traits related to plant growth promotion and their ability to solubilize Morocco rock phosphate (RP) through oxidation of thiosulfate to sulfuric acid. All the tested strains grew in Nfb medium (except Dyella ginsengisoli) and possessed beta-1,3 glucanase activity (except Burkholderia kururiensis). Of the fourteen tested strains, 2 were found positive for siderophore production, 3 each for phytohormones (IAA), and salicylic acid production. Based on qualitative and quantitative assays, 5 strains were found to efficiently solubilize tri-calcium phosphate in Pikovskaya's medium. Nine strains exhibited ACC (1-aminocyclopropane-1-carboxylate) deaminase activity. In gnotobiotic experiments, Pandoraea sputorum ATSB28 which possessed the lowest ACC deaminase (0.44 nM of alpha-Keto butyrate formed min(-1) mg of protein(-1)) activity increased the primary root length of canola by 166%. Inoculation of Pandoraea sp. strain ATSB30 in mixture containing RP and thiosulfate significantly enhanced the water extractable-P (1147 microg P g RP(-1)) and bicarbonate extractable-P (1144 microg P g RP(-1)) on day 45. Glucose amendment resulted in increased RP solubilization as compared to glucose unamended treatments. Thiosulfate oxidizing bacteria tested in this study possessed at least one or more plant growth promoting traits apart from thiosulfate oxidation and solubilized the RP.

Five phosphate-solubilizing bacteria (PSB) used in this study were isolated based on their ability to solubilize tricalcium phosphate (TCP) in Pikovskaya's medium. Among the tested bacterial strains Burkholderia sp. strain CBPB-HIM showed the highest solubilization (363 lg of soluble P ml -1 ) activity at 48 h of incubation. Further, this strain has been selected to assess its shelf life in nutrient-amended and -unamended clay, rice bran and rock phosphate (RP) pellet-based granular formulation. The results showed that the maximum viability of bacterium was observed in clay and rice bran (1:1) + 10% RP pellets than clay-RP pellets, irrespective of tested storage temperatures. Further, clay and rice bran (1:1) + 10% RP pellets amended with 1% glucose supported the higher number of cells compared to glycerol-amended and nutrient-unamended pellets. In this carrier solubilization of Morocco rock phosphate (MRP) by Burkholderia sp. strain CBPB-HIM was also investigated. The maximum of water and bicarbonate extractable P (206 and 245 lg P g -1 of pellet respectively) was recorded in clay and rice bran (1:1) + 10% RP pellets amended with 1% glucose and glycerol respectively on day 5 of incubation. Therefore, this study proved the possibility of developing granular inoculant technology combining clay, rice bran and RP as substrates with phosphate-solubilizing Burkholderia.

et al., 2009). During a study of a thiosulfate-oxidizing bacterial population in field-cultivated sunflower rhizosphere soil, strain ATSB10 T was isolated and found to be a member of the genus Dyella on the basis of 16S rRNA gene Abbreviations: DPG, diphosphatidylglycerol; PDE, phosphatidyldimethylethanolamine; PE, phosphatidylethanolamine; PG, phosphatidylglycerol.

A thiosulfate-oxidizing facultative chemolithoautotrophic Burkholderia sp. strain ATSB13(T) was previously isolated from rhizosphere soil of tobacco plant. Strain ATSB13(T) was aerobic, Gram-staining-negative, rod shaped and motile by means of sub-terminal flagellum. Strain ATSB13(T) exhibited mixotrophic growth in a medium containing thiosulfate plus acetate. A phylogenetic study based on 16S rRNA gene sequence analysis indicated that strain ATSB13(T) was most closely related to Burkholderia kururiensis KP23(T) (98.7%), Burkholderia tuberum STM678(T) (96.5%) and Burkholderia phymatum STM815(T) (96.4%). Chemotaxonomic data [G+C 64.0 mol%, major fatty acids, C(18:1) omega7c (28.22%), C(16:1) omega7c/15 iso 2OH (15.15%), and C(16:0) (14.91%) and Q-8 as predominant respiratory ubiquinone] supported the affiliation of the strain ATSB13(T) within the genus Burkholderia. Though the strain ATSB13(T) shared high 16S rRNA gene sequence similarity with the type strain of B. kururiensis but considerably distant from the latter in terms of several phenotypic and chemotaxonomic characteristics. DNA-DNA hybridization between strain ATSB13(T) and B. kururiensis KP23(T) was 100%, and hence, it is inferred that strain ATSB13(T) is a member of B. kururiensis. On the basis of data obtained from this study, we propose that B. kururiensis be subdivided into B. kururiensis subsp. kururiensis subsp. nov. (type strain KP23(T) = JCM 10599(T) = DSM 13646(T)) and B. kururiensis subsp. thiooxydans subsp. nov. (type strain ATSB13(T) = KACC 12758(T)).

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Adhirasam is a cereal based, doughnut shaped, deep fried dessert consumed in the southern regions of India. The dough used to prepare adhirasam is fermented and contains rice flour and jaggery. The aim of the present study was to characterize the cultivable bacteria associated with this fermented dough and to identify a suitable starter culture for the production of quality adhirasam. In total, one hundred and seventy bacterial isolates were recovered from de Man Rogosa Sharp (MRS) agar, nutrient agar, lysogeny agar and tryptic soy agar media. Out of the 170 bacterial isolates, sixteen isolates were selected based on their ability to tolerate glucose and sucrose. All the bacterial isolates tolerated 15% glucose and 30% sucrose. Analyses of 16S rDNA gene sequences of the bacterial isolates showed that the dominant cultivable bacteria were members of the genus Bacillus. These strains were further used as starters and tested for their ability to ferment rice flour with jaggery to produce adhirasam dough. Organoleptic evaluation was carried out to choose the best starter strain. Adhirasam prepared from Bacillus subtilis isolates S4-P11, S2-G2-A1 and S1-G15, Bacillus tequilensis isolates S2-H16, S3-P9, S3-G10 and Bacillus siamensis isolate S2-G13 were highly acceptable to consumers. Adhirasam prepared using these starter cultures had superior product characteristics such as softness in texture, flavor and enhanced aroma and sweet taste.

Insecticidal seed treatment is an alternative method to spray and granular applications. It can protect the crop right from germination to reproductive stage. Recurrent use of chemical insecticides destabilizes the ecosystem and enhances the development of resistance in pest population. Use of biopesticides like neem oil (NO) is a promising one in this situation. Two field experiments were conducted to test the efficacy of NO as a seed dresser (20 ml kg À1 ) and the effect was compared with systemic chemical insecticides imidacloprid (7 g kg À1 ) and carbosulfan (7 g kg À1 ) and Pseudomonas fluorescens (10 g kg À1 ). Field studies revealed that the neem oil 60EC (C) (NO 60EC (C)) recorded minimum population of sucking pests Leafhopper-Amrasca biguttula biguttula Ishida and Aphids-Aphis gossypii Glover (Homoptera: Cicadellidae and Aphididae), i.e., below the ETL (2 number per leaf) up to 45 days after sowing and provided better yield compared to control. Although the systemic chemical insecticide imidacloprid performed better by recording 11,280 and 11,580 kg ha À1 of marketable fruit yield, NO 60EC (C) also recorded about twofold increase in marketable fruit yield 11,000 and 10,620 kg ha À1 , respectively, in 2001 and 2002 experiments. Results of this study suggest that NO could be used as a potential seed dresser for managing sucking pests in okra.

Purpose Traditional organic formulations are widely used as a plant growth promoters; however, the knowledge on the microbial aspect of traditional organic formulations is still limited. The aim of this study was to illustrate the cultivable bacterial diversity of various traditional organic formulations and their potential for early plant growth promotion. Methods Five different traditional organic formulations such as 100 % panchagavya, 33 % panchagavya, plant extract with native microorganisms, commercial organic fertilizer extract with two percent leaf soil extract and commercial organic fertilizer extract with 2 % yogurt were prepared and used in this study. The liquid fraction of these traditional organic formulations were used to analyze the beneficial effect on plant growth by seed treatment and foliar applications.Results Bacterial 16SrDNA analysis revealed that the isolates fell into forty-three different genera, which can be grouped into seven different classes, such as Alphaproteobacteria, Actinobacteria, Bacilli (or Firmibacteria), Betaproteobacteria, Cytophagia, Flavobacteriia and Gammaproteobacteria. Higher bacterial diversity was observed in cow dung followed by 33 and 100 % panchagavya. Radish and Chinese cabbage seed germination and growth were significantly improved by traditional organic formulations compared to control. Conclusion The results of this study showed that the bacterial diversity changes depend on the type and concentration of ingredients used in traditional organic formulations. Substantial increase in plant growth by the traditional organic formulations indicates the suitability of using these organic preparations in eco-friendly agriculture.