Cultivated methanotrophs associated with rhizospheres of traditional rice landraces from Western India belong to Methylocaldum and Methylocystis
Aerobic methanotrophs associated with Indian rice plants have rarely been cultivated. In the present study, we cultured aerobic methanotrophic bacteria from the rhizosphere regions of rice plants. Rhizospheric soils from seven rice landraces traditionally grown and maintained by tribal people in Jawhar region belonging to part of the Western Ghats in India, were used. Seven methanotrophic cultures were isolated from the last positive dilution (10− 4). Methanotrophs were identified by analyzing the partial methane monooxygenase gene, pmoA gene and three of these belonged to the genus Methylocaldum (gammaproteobacterial, Type I methanotrophs) and four belonged to the genus Methylocystis (alphaproteobacterial, Type II methanotrophs). We present here the first report on the cultivation of methanotrophs from Indian traditional rice landraces originating from a biodiversity hotspot.
KeywordsMethanotrophs Rice rhizosphere Aerobic Methane-oxidizing bacteria Cultivation PmoA Rice landraces Western Ghats
We thank Pranitha S. Pandit MACS, Agharkar Research Institute for the help during DNA isolation of the cultures.
MCR and RAB planned the work, wrote the manuscript and prepared figures and tables. SP maintained the rice landraces at Jawhar and also did the sampling. RAB performed initial processing of samples and helped in phylogenetic analysis. MCR did all the microbiological and molecular biological work. PKD reviewed the work and helped in writing the manuscript.
This work was partially supported by DBT BioCARe program (BT/BioCARe/06/840/2012) sanctioned to MCR. We thank both the institutes for providing institutional funds.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interests.
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