International Journal of Agricultural Policy and Research
ISSN 2350-1561 Vol.3 (5), pp. 242-250,May 2015
Available online at https://www.journalissues.org/IJAPR/
Article 15/ID/JPR41/09/ pages
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License.
Original Research Article
Common bean (Phaseolus vulgaris L.) and soya bean (Glycine max) growth and nodulation as influenced by rock phosphate solubilising bacteria under pot grown conditions
Henri Fankem1*, Gylaine Vanissa Tchuisseu TChakounte1, Laurette Ngo nkot1, Hélène Laure Mafokoua1, Donald Tchouomo Dondjou1, Claude Simo1, Dieudonné Nwaga2 and François-Xavier Etoa2.
1Department of Plant Biology, Faculty of Science, University of Douala, P.O. Box 24157 Douala, Cameroon. 2Department of Microbiology, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon. *Corresponding Author: E-mail: fankemhenri(at)yahoo.fr Tel: (+237) 699 83 89 69;671 38 23 56
Phosphate solubilising bacteria (PSB) is an alternative for increasing the availability of accumulated phosphates through solubilisation, enhancing plant growth by increasing the efficiency of biological nitrogen fixation. Phosphate solubilising bacteria from acidic soils of Cameroon were screened for their phosphate solubilising ability on plate cultures containing inorganic/organic phosphates including calcium-phosphate (Ca3(PO4)2), aluminium-phosphate (AlPO4), iron-phosphate (FePO4), sodium-phytate as well as rock phosphates (RP) of different origins (Mali, Mexico and Morocco). They were subsequently tested on common and soya bean grown in pots filled with non-sterile and sterile soils amended with Malian rock phosphate for their aptitude in promoting plant growth and nodulation. The average index of solubilisation of the tested bacterial strains were 3.43 for calcium phosphate, 6.6 for aluminium phosphate, 4.12 for iron phosphate and 2.59 for sodium phytate. The index of solubilisation of the natural rock phosphates ranged from 1.33-2.71 with an average of 2.01. Enterobacter sp. was the only strain showing halo zone on plates with all the different insoluble phosphates. Based on the average effect of inoculation on growth and nodulation, Pseudomonas sp. was the strain showing the greatest result among the single inoculation treatments with an average of 251% for common bean, while Enterobacter sp. was the strain showing the greatest result among the single inoculation treatments with an average of 231.4% effect for soya bean plants. In both cases, the consortia BCD (Pseudomonas sp.+ Burkholderia sp.+ Enterobacter sp.) were the best among the different cocktails with an average of 162.5% and 197% for common and soya bean respectively. These results suggest that the use of rock phosphate combined with the co-inoculation of phosphate solubilising bacterial strains in soil with low fertility provides a sustainable alternative to the use of industrial fertilisers for both common and soya beans production.
Key words: Phosphate solubilising bacteria, phosphate solubilisation, common bean, soya bean, growth, nodulation.