Research Journal of Microbiology1816-4935xxxx-xxxxScience International10.3923/jm.2011.618.624Azotobacter chroococcum in Rooting and Growth of Eucalyptus camaldulensis Stem Cuttings]]>KarthikeyanA. SakthivelK.M. 7201167Eucalyptus camaldulensis Dehn is a commercial tree crop mainly for paper and pulp industries. This tree crop is propagated by vegetative propagation method to obtain genetically superior clones. At the time of vegetative propagation a synthetic rooting hormone Indole Butyric Acid (IBA) is being used in nurseries for successful rooting in E. camaldulensis stem cuttings. To reduce the cost of IBA and improve the rooting and nutrient enrichment as an alternate method a nitrogen fixing bacteria Azotobacter chroococcum was applied in the stem cuttings of E. camaldulensis in present study. The influence of A chroococcum on rooting and subsequent growth of E. camaldulensis cuttings was observed under nursery conditions. An un-inoculated control and IBA treated cuttings were also maintained to compare the growth with A. chroococcum inoculated stem cuttings. Bacterial inoculum (5x107 cfu mL-1 ) at the rate of 5 and 10 mL were applied to the rooting substrate (vermiculite) during cutting installation. Rooting and Biomass was evaluated after 30 days of cutting installation. Additionally, the isolates were screened for their ability to produce Indole Acetic Acid (IAA) under in vitro conditions either in the presence or absence of tryptophan at different concentrations. The results revealed that A. chroococcum produced significant quantities of IAA for root initiation and A. chroococcum inoculated cuttings had higher growth than IBA treated cuttings at p<0.05. From this study, it was concluded that the stem cuttings of E. camaldulensis responded positively to A. chroococcum inoculation through increased root proliferation and growth.]]>Akbari, G.A., S.M. Arab, H.M. Alikhani, H.A. Allahdadi and M.H. Arzanesh,2007Azospirillum spp. and the IAA of superior strains effects on wheat roots.]]>3523529Bottini, R., F. Cassan and P. Piccoli,200465497503Brown, M.E.,1976Azotabacter paspali in association with Paspalum notatum.]]>40341348Cappuccino, J.C. and N. Sherman,1992Das, P.K., A. Ghosh, R.S. Katiyar and K. Sengupta,1990Azotobacter and Azospirillum biofertilizers under graded levels of nitrogen.]]>31255261Dart, P.J.,197690303334Dhamangaonkar, S.N. and P. Misra,2009Azotobacter chroococcum (PGPR) on the Growth of Bamboo (Bambusa bamboo) and Maize (Zea mays) Plant.]]>13746Enebak, S.A., A. Wei and J.W. Kloepper,1998454139144Fallik, E., Y. Okon and M. Fischer,1998Azospirillum inoculation: Effect of soil organic matter content, number of rhizosphere bacteria and timing of inoculation.]]>204549Faisal, M. and S. Hasnain,2010Brevibacterium under chromium stress.]]>54348Fatima, Z., M. Saleemi, M. Zia, T. Sultan, M. Aslam, Riaz-ur-Rehman and M.F. Chaudhary,2009Rhizoctonia solani in wheat.]]>8219225Glick, B.R., C.L. Patten, G. Holguin and D.M. Penrose,1999Jain, D.K. and D.G. Patriquin,1985Azospirillum which causes branching of wheat root hairs.]]>31206210Karthikeyan, A. and M. Suryaprakash,2008Azospirillum sp. on successful establishment of Eucalyptus camaldulensis Dehn. in Bauxite Mine Spoils.]]>18183191Kebebew, Z.,20104202207Kumar, T., M. Ghose and R.L. Brahmachary,2007in vitro spore germination and hyphal growth of Glomus mosseae.]]>24853Kloepper, J.W., J. Leong, M. Teintze and M.N. Schroth,1980286885886Loper, J.E. and M.N. Schroth,198676386389Mohammad, G. and R. Prasad,1998Eucalyptus calmadulensis seedlings.]]>47477Mostafa, G.G. and M.F.A. Alhamd,2011Balanites aegyptiaca plants.]]>63643Panaiyadiyan, P. and S.R. Chellaia,201152735Shaukat, K., S. Affrasayab and S. Hasnain, 2006Triticum aestivum to plant growth promoting rhizobacteria used as a biofertilizer.]]>1330338Taiz, L. and E. Zeiger,19981998pp: 543-589pp: 543-589Verma, S., V. Kumar, N. Narula and W. Merbach,2001in vitro production of antimicrobial substances by Azotobacter chroococcum isolates/mutants.]]>108152165Vikram, A. and H. Hamzehzarghani,2008Vigna radiata L. Wilczek).]]>36272Vinutha, T.,2005Ocimum species inoculated with microbial inoculants.]]>2005Woyessa, D. and F. Assefa,2011Eragrostis tef Zucc. Trotter) under greenhouse condition.]]>6343355Yeboah, J., S.T. Lowor and F.M. Amoah,2009Vitellaria paradoxa C.F. Gaertn) cuttings leached in water and application of rooting hormone in different media.]]>41014