Identification of bacteria species in aquaponics system using RapID system and 16S rRNA sequencing

Abstract

Aquaponics is an integrated production system of aquaculture and hydroponics. Beneficial bacteria convert the ammonia and solid wastes produced by fish in the aquaculture component into essential nutrients for plant growth in hydroponics. The objective of the present study was to identify the bacteria community in the aquaponics system. This study was set by using barb fish and basils as organisms of cultivation. The fish tank (aquaculture) water was pumped into the treatment tank containing bio-ring functions as nitrifying bacteria by converting ammonia to nitrates. The nutrient-rich water from the treatment tank was then pumped into the hydroponics containing lightweight expanded clay aggregate (LECA) and plants. Water samples from the treatment tank and hydroponics were pipetted and transferred onto different agar plates for colony growth. Another set of soil growth plant was used for comparison in bacteria community between aquaponics and conventional land agriculture. RapID system and 16S rRNA gene were used to identify gram-negative and gram-positive bacteria respectively. The identified bacteria species from the hydroponics (LECA) and treatment tank (Bio-ring) were Moellerella wisconsensis, Achromobacter xylosoxidans, Bacillus cereus, Burkholderia pseudomallei and Bacillus sp. respectively whereas the bacteria species isolated from soil were Bacillus sp. and Bacillus pumilus.