Browsing by Author "S N, Padma Devi"

Now showing 1 - 4 of 4

ASSESSMENT OF COMPETENCE OF THE PSEUDOMONAS AERUGINOSA TO SOLUBILIZE INSOLUBLE FORM OF ZINC UNDER VARIOUS CULTURAL PARAMETERS
(Springer, 2016) S N, Padma Devi; K, Sunitha kumari; S, Vasandha
Efficiency of Pseudomonas aeruginosa to solubilize insoluble form of zinc to soluble form was studied under various cultural parameters such as carbon (Glucose, Fructose, Sucrose, Maltose and Lactose), nitrogen (Ammonium sulphate, Sodium nitrate, Potassium nitrate and Urea), pH (5.0, 7.0 and 9.0) and temperature (20°C, 30°C and 40°C). The experimental study was carried out by both qualitative (Plate assay) and quantitative (Broth assay) method. The Zn solubilizing efficiency of the isolate was found more when glucose was added as C-source in both plate (150%) and broth assay (16.62mg/l) and the efficiency was less in the medium amended with sucrose as carbon source in both qualitative (105.8%) and quantitative estimation (2.56mg/l). Among the four nitrogen sources Pseudomonas aeruginosa showed best solubilizing efficiency (262.5%) and solubilization of Zn (29.91mg/l) in the presence of Ammonium sulphate and recorded least solubilization efficiency in the presence of Sodium nitrate as nitrogen source in both plate (181.82%) and broth assay (21.92mg/l). It showed highest solubilization of zinc from ZnO at the incubation temperature of 30°C and the activity was less at the temperature of 40°C. pH 7 was the most favorable pH for solubilization and the efficacy was least when the pH reached its alkalinity. Thus the study confirmed the efficiency of Pseudomonas aeruginosa to solubilize insoluble form zinc and can be used as a source of bioinoculants to eradicate zinc deficiency in plants.
PHOSPHORUS SOLUBILIZING ACTIVITY OF MYCOBACTERIUM COSMETICUM UNDER VARIOUS CULTURAL CONDITIONS
(International Journal of Advanced Scientific Research and Management, 2018) K, Sunitha kumari; S N, Padma Devi; K, Nisha
Effect of various cultural conditions on the phosphorus solubilizing activity of Mycobacterium cosmeticum was tested under different parameters such as carbon (Glucose, Fructose, Sucrose, Maltose and Lactose), nitrogen (Ammonium sulphate, Sodium nitrate, Potassium nitrate and Urea), pH (5.0, 7.0 and 9.0) and temperature (25°C, 35°C and 45°C) using Pikovskaya’s medium amended with 0.5% tri calcium phosphate (TCP) as an insoluble source of P. Solubilization efficiency of TCP by M.cosmeticum varied with different carbon and nitrogen sources in both plate and broth assay. The results of plate assay revealed that P-solubilizing ability of the isolate was more in the presence of glucose (237.3%) as C-source and potassium nitrate (140.2%) as N-source. Whereas for the broth assay lactose was found to be the best (9.0 mg/l) and ammonium sulphate was the best nitrogen source (6.5mg/l). The isolate exhibited its maximum ability to solubilize TCP at the pH of 7.0 and at the incubation temperature of 35°C in both the assays. Thus the study confirmed the efficiency of M.cosmeticum to solubilize insoluble form of P under various cultural conditions and can be used as a source of Bioinoculants to eradicate P deficiency in plants and this study was the first to report P-solubilizing activity of M.cosmeticum.
ROLE OF PHOSPHOROUS SOLUBILIZING MICROORGANISMS TO ERADICATE P-DEFICIENCY IN PLANTS-A REVIEW
(International Journal of Scientific and Research Publications, 2014) K, Nisha; S N, Padma Devi; S, Vasandha; K, Sunitha kumari
Phosphorus is the second most important macro nutrient required by the plants for its optimum growth and yield. But it is considered to be a most limiting factor of many crop production systems, due to its unavailability of soluble forms in the soils. About 80% of applied P fertilizers are immobilized due to the formation of complex with Al or Fe in acidic soils or Ca in calcareous soils. An alternative way to circumvent P deficiency in soil and to improve crop production is through the utilization of microorganisms as biofertilizer. Rhizospheric microorganisms play a vital role in the transformation of unavailable form of P into available form which will be a boon to the agrarian communities to remove P deficiency in plants.
ZINC SOLUBILIZING BACTERIAL ISOLATES FROM THE AGRICULTURAL FIELDS OF COIMBATORE DISTRICT, TAMIL NADU
(Current science Association and Indian Academy of Sciences, 2016) K, Sunitha kumari; S N, Padma Devi; S, Vasandha
Zinc plays a pivotal role in physiological and biochemical functions of the plants. Both quantitative and qualitative yield of the plants are strongly dependent on this micronutrient. Supplementation of zinc in the form of synthetic fertilizer is proved to be inappropriate due to its unavailability to plants. This crisis can be prevented by the identification of rhizospheric micro-organisms which has the potential to transform various unavailable forms of the metal to available forms. In the present study about thirty five zinc solubilizing bacteria were isolated from eight different agricultural fields (banana, chilli, field bean, ground nut, maize, sugarcane, sorghum and tomato) in and around Coimbatore district of Tamil Nadu. Five isolates were selected as best strains based on their solubilization efficacy in the qualitative estimation. The selected five isolates were identified using 16S rRNA as Stenotrophomonas maltophilia (ZSB-1), Mycobacterium brisbanense (ZSB-10), Enterobacter aerogenes (ZSB-13), Pseudomonas aeruginosa (ZSB- 22) and Xanthomonas retroflexus (ZSB-23). These strains were subjected to further studies such as quantitative estimation, influence of the isolates on the pH of the medium and production of gluconic acid as well as IAA. Of the five bacterial isolates, Pseudomonas aeruginosa showed maximum solubilization of zinc in the broth and also maximum decrease in the pH from 7 to 3.3 and recorded highest IAA production. HPLC analysis of gluconic acid production by the selected isolates indicated their potential to solubilize zinc.