Study of Plant Growth Promoting Bacteria from Coconut Coir Dust

Coconut coir dust or commercially known as cocopeat was a waste product of the coconut industry and was used as growing medium. Coconut coir dust as an environmentally sound peat substitute in soilless growing medium for crop production due to suitable physical and chemical properties. Plant growth-promoting bacteria (PGPB) are bacteria that can enhance plant growth and protect plants from disease and abiotic stresses through a wide variety of mechanisms. The objective of this study are to isolate and characterize PGPB from coconut coir dust including phosphate solubilization, indole acetic acid (IAA) production, protease enzyme and siderophore production also lignin and cellulose degradation activity. Total 40 isolates PGPB bacterial isolates were isolated and screened for their various activities and the result showed that 16 isolates have highest activity of PGPB. Four isolates in case of IAA production and CP.2AT Isolate can produce IAA 28 ppm by High Performance Liquid Chromatography analysis, 3 isolates shown protease enzyme production ( halo zone 1, 6 - 2, 2 cm ), 5 isolates were confirmed have phosphate-solubilizing activity, 2 isolates have shown lignin degradation activity, 2 isolates were confirmed of cellulose degradation activity and 8 isolates have ability to production of siderophore. In addition composted coconut coir dust contain much more total of PGPB and lower C/N ratio than fresh coconut coir dust. Composting of coconut coir dust increased number of lignin and cellulose degradation bacteria. This results of this study indicated that coconut coir dust potentially for growing medium with high activity of plant growth promoting bacteria.