Antifungal activity of bacteria isolated from Sabah Tea Plantation against Fungi isolated from diseased tea roots

• Main Author: Ng, Ja Ming
• Format: Academic Exercise
• Language: English
• Published: 2015
• Subjects: SB Plant culture
• Online Access: https://eprints.ums.edu.my/id/eprint/16954/1/antifungal_activity_of_bacteria_isolated.pdf; https://eprints.ums.edu.my/id/eprint/16954/

A laboratory experiment was conducted at the Faculty of Sustainable Agriculture in Universiti Malaysia Sabah from 26th June 2014 to 18th October 2014 to study the effect of antifungal activity of bacteria isolated from Sabah Tea Plantation against fungi isolated from disease tea roots. Soil bacteria from Sabah Tea Plantation, Ranau were isolated and investigated their effectiveness against several fungi. Dual culture assay, Nutrient agar amended with bacteria culture test, mycelia growth test and bacteria culture filtrate were carried out to test the antifungal activity of bacteria against several fungi isolated from the disease tea roots. After undergoing preliminary selection, 20 groups of rhizopheric bacteria were successfully obtained. Preliminary screening of these bacterial isolates for antagonistic activity using dual culture assay had been carried out. The effectiveness of the antagonism character were evaluated based on the percentage inhibition radial growth (PIRG) and percentage inhibition diameter growth (PIDG). Among the 20 groups of isolated bacteria, only four bacterial isolates(Ai, A2, A4 and A14) showed potential antagonistic activity toward fungi (GD, F4, F5,and F9). They were significant effect on the interaction between bacteria and fungi in Nutrient agar amended with bacteria culture test {F (9, 48) = 33.835, p<0.05} and mycelial growth test {F (9, 48) = 45.585, p<0.05}. Bacterial isolate A1 and A2 even showed 100% PIDG toward fungi F4 in Nutrient agar amended with bacteria culture test and bacterial A14 had 94.67% PIDG toward fungi F4 in mycelial growth test. These bacteria were then identified with Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and the isolate A1 was Bacillus cereus, A2 was Pseudomonas aeroginosa, A4 was Streptomyces grises and A14 was Serratia marcescens.