International Journal of Applied Agricultural Research ISSN 0973-2683 Volume 6 Number 1 (2011) pp. 2933 Research India Publications http://www.ripublication.com/ijaar.htm

Phosphorous Solubilizing Pseudomonas Aeruginosa PMV-14 Enhance Productivity in Rice Crop*Vishal K. Deshwal, Reena, Prerana Sharma, Sonal Gupta, Maumita Chakraborty and Tanushri Chatterji Department of Microbiology, Doon (PG) Paramedical College, 28, Chakrata Road, Dehradun (Uttarakhand)-248001 (India) *Correspondence Author E-mail id: vishal_deshwal@rediffmail.com

Abstract Aim of present study was isolation of Plant growth promoting Pseudomonas from cultivated rice soil. Total 25 characterized Pseudomonas strains were select and only 4 best phosphorous solubilizing Pseudomonas PMV-3, PMV7, PMV-8, PMV-14 and non-Phosphorus solubilizing Pseudomonas PMV-19 were selected for further field experiment. Results indicated that Pseudomonas PMV-14 bacterized rice seeds enhanced shoot length, root length, dry weight and grain yield by 157, 134.9, 297 and 229% respectively as compared to nonbacterized rice seeds. Further, non-Phosphorus solubilizing Pseudomonas PMV-19 produced less grain yield as compared to non-phosphorus solubilizing Pseudomonas. But Pseudomonas PMV-19 increased shoot length, root length, dry weight and grain yield by 153, 120, 231 and 146% respectively as compared to non-bacterized rice seeds. Keywords: Plant Growth Promoting Rhizobacteria, Phosphate Solubilizing Bacteria, Pseudomonas, rice crop.

IntroductionPhosphorous (P) is major essential macronutrient for plant growth and development. Consequently to achieve optimum crop yields, soluble phosphate fertilizers have to be applied at high rates (1). Such soluble inorganic fertilizer in soil is immobilized rapidly and become unavailable to plants (2). Use of chemical fertilizer causes soil erosion and lower crop yield (3). Recently, Mai et al (4) mentioned that excess use of chemical fertilizer is undesirable because (i) production of chemical fertilizer is a costly process, (ii) most of the energy is provided by consumption of non-renewable fossil fuel, (iii)

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considerable pollution is caused through both the production and use of mineral Nfertilizer. Deshwal and Vig (5) reported that Plant growth promoting rhizobacteria (PGPR) effectively colonized and enhanced seed germination, shoot length, root length, fresh seedling weight, dry seedling weight and nodule number in peanut plant (Arachis hypogaea L.). Previously, Deshwal et al (6,7) observed that Plant growth promoting rhizobacteria (PGPR) enhanced plant growth by producing IAA and Psolubilization. The ability of a few soil microorganisms to convert insoluble form of phosphorus to an accessible form is an important trait in plant growth promoting bacteria for increasing plant yields (8). The use of plant growth promoting rhizobacteria (PGPR) including phosphate solubilizing bacteria (PSB) as biofertilizers, was suggested as sustainable solution to improve plant nutrient and promotion (9). PGPR enhanced seed germination, seedling growth and yield of crop had been reported by Gholami et al (10). So aim of present study is to isolation of phosphate solubilizing Pseudomonas from cultivated Rice crop and evaluated effect of PSB on productivity of Rice crop.

Materials and Methodsa. Isolation and purification of Pseudomonas stains: Pseudomonas strains were isolated from cultivated Rice soil. 1g of soil dissolved in 9ml sterilized distilled water in test tube and mixed well. Sample was diluted up to 105. 0.5ml sample of each tube was spread on separate Kings B Agar plates. Plates were incubated at 37oC for 24h. Fluorescent colonies on agar medium were purified. b. Characterization of Pseudomonas strains: Twenty isolates strains were characterized on the basis of gram staining and bio-chemicals tests. Such tests were done according to Bergey's Manual of Determinative Bacteriology (11). c. Screening of the Phosphate solubilizing Pseudomonas: Characterized Pseudomonas strains were transfer on Pikovskyas Agar medium and inoculated at 281oC for 3-5days and clear zone around the colony showed Psolubilization (6). d. Field trails: Out of twenty, only four best P-solubilizing Pseudomonas PMV-3, Pseudomonas PMV-7, Pseudomonas PMV-8, Pseudomonas PMV-14 and one non-phosphorous solubilizing Pseudomonas PMV-19 were selected for further field experiment. Rice seeds were bacterized according to Deshwal et al (6). Seeds bacterized with Pseudomonas along with non-bacterized seeds (control) were sown in six sets of treatment: treatment I Pseudomonas PMV-3; treatment II Pseudomonas PMV-7; treatment III Pseudomonas PMV-8; treatment IV Pseudomonas PMV-14, treatment V Pseudomonas PMV-19 and treatment VI Non-bacterized seed. The plants were irrigated with tap water whenever required. Seed germination (%) was noted on 15th day of sowing. Seedling shoot length, root length, dry weight and grain yield were calculated at harvesting time.

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Results and DiscussionSelection and isolation of residential Pseudomonas strains was important because such residual Pseudomonas strains easily survive in Rice field and colonize effectively in Rice rhizosphere or rice field. Fluorescent colonies of strains on Kings B agar medium were purified and characterized on the basis of biochemical test. Isolated strains were marked PMV-1 to PMV-20. On the basis of bio-chemicals tests, isolated strains were Pseudomonas. Similar observations had been mentioned in Bergey's manual of Determinative Bacteriology (11). Clear zone around the colony of Pseudomonas on Pikovskyas Agar medium showed P-solubilizing positive and if no clear zone around the colony indicated that strains failed to solubilize Phosphate. Four best P-solubilizing Pseudomonas aeruginosa PMV-3, Pseudomonas fluorescens PMV-7, Pseudomonas fluorescens PMV-8, Pseudomonas aeruginosa PMV-14 and one non-phosphorous solubilizing Pseudomonas aeruginosa PMV-19 were selected for further study. Deshwal et al (6) reported that Plant growth promoting rhizobacteria soluble phosphate and increase plant growth. Similarly, Rajankar et al (12) also screened the same manner. Panhwar et al (13) observed that phosphorus solubilizing bacteria were able to solubilize P from tricalcium phosphate and rock phosphate. After harvesting of Rice crop, results suggested that P- solubilizing Pseudomonas PMV-14 enhanced maximum shoot length, root length, dry weight and grain yield by 157, 134.9, 297 and 229% respectively as compared to control rice plant. Nonphosphorus solubilizing Pseudomonas PMV-19 increased shoot length, root length, dry weight and grain yield by 153, 120, 231 and 146% respectively as compared to non-bacterized rice seeds. But PMV-19 did not produce more grain yield as compared to Phosphorous solubilizing Pseudomonas. Seed germination is not significantly increase. Other strains of Pseudomonas were also enhanced growth and productivity (Table 1). Previously, Deshwal et al (7) reported the long term effect of Pseudomonas aeruginosa GRC1 on yield of subsequent crops of paddy after mustard seed bacterization. Again, some reports indicated that application of Phosphatesolubilizing bacteria plant growth productivity in soybean (14, 15), Cicer arietinum (16). Akhtar and Siddiqui (17) observed that phosphorous solubilizing microorganism enhanced plant growth, nodulation, yield of chickpea under field condition.

Table 1: Effect of bacterization with Pseudomonas- PMV-3, Pseudomonas- PMV-7, Pseudomonas- PMV-8, Pseudomonas- PMV-14 and Pseudomonas- PMV-19 on the growth of Rice crop. SN Treatment Seed Length (cm) germinationns Shoot* Root* 97 89.9 9.5 96 85.4 10.2 Dry weight (gm) Seedling** 9.44 8.22 Grain yield (gm)** 9.2 8.7

1 2

Pseudomonas PMV-3 Pseudomonas PMV-7

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Pseudomonas 95 86.2 10.5 8.60 7.3 PMV-8 4 Pseudomonas 97 91.7 11.2 10.1 9.4 PMV-14 5 Pseudomonas 97 89.5 10.0 7.86 6.0 PMV-19 6 Control 95 58.4 8.3 3.4 4.1 Values are mean of ten replicates; ns- non-significant at 0.05 level of ANOVA *significant at 0.05 level of ANOVA, **- significant at 0.01levels of ANOVA.

Such report supports our results that plant growth promoting rhizobacteria increase the plant growth and productivity. And we conclude that P-solubilizing Pseudomonas provides insoluble form of phosphorus to an accessible form and as a result growth of rice crop as well as grain yield was increased. Such bio-fertilizer would sustainable solution to improve plant growth and productivity.

References[1] [2] [3] Brady, N.C., 1990, The nature and properties of soils, Macmillan, New York, USA, pp. 351-380. Goldstein, A.H., 1986, Bacterial solubilization of mineral phosphates: historical perspectives and future prospects, Am. J. Alt. Agr., 1, pp. 57-65. Kumar, M.V.N., and Kumar, S.S., 2000, Studies on character association and path efficient for grain and oil content in maize, Annals of Agr. Res., 21, pp. 73-78. Mai, M.A.B., Shamsuddin, Z.H., Wahab, Z., and Marziah, M., 2010, Effect of plant growth and nitrogen incorporation of tissue-cultured Musa plantlets under nitrogen free hydroponics condition, Aus. J. Crop Sci., 4(2), pp. 85-90. Deshwal, V.K., and Vig, K., 2010, Effect of co-inoculation of PseudomonasMP3 and Rhizobium-GR23 on plant growth of peanut (Arachis hypogaea L.), J. Plant Development Sci., 2 (1&2): 61-62. Deshwal, V.K., Dubey, R.C., and Maheshwari, D.K., 2003, Isolation of plant growth-promoting strains of Bradyrhizobium (Arachis) sp. with biocontrol potential against Macrophomina phaseolina causing charcoal rot of peanut, Curr. Sci., 84, pp. 443-448. Deshwal, V.K., Kumar, T., Dubey, R.C., and Maheshwari, D.K., 2006, Long term effect of Pseudomonas aeruginosa GRC1 on yield of subsequent crops of paddy after mustard seed bacterization, Curr. Sci., 91(4), pp. 423-424. Chen, Y.P., Rekha, P.D., Arun, A.B., Shen, F.T., Lai, W.A., and Young, C.C., 2006, Phosphate solubilizing bacteria from subtropical soil and their tricalcium phosphate solubilizing abilities, Appl. Soil Ecol., 34, pp. 33-41. Vessey, K.J., 2003, Plant growth promoting rhizobacteria as biofertilizers, Plant Soil, 255, pp. 571-586.

[4]

[5]

[6]

[7]

[8]

[9]

Phosphorous Solubilizing Pseudomonas Aeruginosa PMV-14 [10]

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[11]

[12]

[13]

[14]

[15]

[16]

[17]

Gholami, A., Shahsavani S., and Nezarat, S., 2009, The effect of plant growth promoting Rhizobacteria (PGPR) on germination, seedling growth and yield of maize, World Academy of science, Engineering and technology A: Biological and Biomedical Science, 5, pp. 35-40. Holt, J.G., Krieg, N.R., Sneath, P.H.A., Staley, J.T., and Williams, S.T., 1994, In, Bergey's manual of Determinative Bacteriology, Williams and Wilkins Press, Baltimore, USA: 9th edition, 112, pp. 151-157. Rajankar, P.N.,Tambekar, D.H., and Wate, S.R., 2007, Study of Phosphate Solubilization Efficiencies of Fungi and Bacteria Isolated From Saline belt of Purna river basin, Res. J. Agri. and Biol. Sci., 3(6), pp. 701-703. Panhwar, Q.A., Radziah, O., Sariah, M., and Ismail, M.R., 2009, Solubilization of different Phosphate forms by phosphate solubilizing bacteria isolated from Aerobic rice, Int. J. Agr. and Biol., 11, pp. 667-673. Tran, T.N.S., Cao, N.D., and Truong, T.M.G., 2006, Effect of Bradyrhizobia and phosphate solubilizing bacteria application on soybean in rotational system in the MeKong delta, Omonrice, 14: 48-57. 15] Son, T.T.N.; Diep, C.N., and Giang, T.T.M., 2006, Effect of bradyrhizobia and phosphate solubilizing bacteria application on Soybean in rotational system in the Mekong delta, Omonrice, 14, pp. 48-57. Sharma, K., Dak, G., Agrawal, A., Bhatnagar M., and Sharma R., 2007, Effect of phosphate solubilizing bacteria on the germination of Cicer arietinum seeds and seedling growth, J. Herb. Med. & Toxicol., 1, pp. 6163. Akhtar, M.S., and Siddiqui, Z.A., 2009, Effect of phosphate solubilizing microorganisms and Rhizobium sp. On the growth, nodulation, yield and rootrot disease complex of chickpea under field condition, Afr. J. Biotech., 8, pp. 3489-3496.

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