Beneficial Microorganisms in Bio–compost and Their Potential as Biological Control Agents for Fusarium Wilt of Banana (June 2010)

INTRODUCTION
This study explored the potential of the microorganisms in the bio–compost and biocontrol agents as treatment against Fusarium wilt caused by Fusarium oxysporium f. sp. cubense race 4(FocR4) and as growth promoter of susceptible banana ramets variety Berangan cv. intan. The microorganisms in the bio–compost and the biocontrol agents (preparation of Trichoderma inoculants from Legenda Madu Sdn Bhd) were established as effective; improving growth, vigour and enhancing tolerance of Berangan to Fusarium wilt.

MATERIALS AND METHODS
The bio–compost and biocontrol agents were obtained from Legenda Madu Sdn Bhd. The banana ramets were grown in soil mixed with bio–compost, biocontrol agents and fusarium to determine its effects on the banana ramets. This experiment was conducted for a period of 40 days in a green house.

RESULTS
The effects of the bio–compost and biocontrol agents against fusarium wilt can be seen from the pictures below. A control pot containing only fusarium and soil shows that the banana ramet has died while the banana plants treated with bio–compost and biocontrol agent remained healthy. This indicates that the microbes contained in the bio–compost and biocontrol agents are an effective treatment for fusarium wilt.

Effects of Bio–Compost and Biocontrol Agent on Banana Ramets infected with Fusarium oxysporium

Soil + Biocontrol Agent + Fusarium Oxysporium	100% Bio–compost + Fusarium Oxysporium	Bio–compost mixed with Soil at 2:1 Ratio + Fusarium Oxysporium
Bio–compost mixed with Soil at 1:1 Ratio + Fusarium Oxysporium	Bio–compost mixed with Soil at 1:2 Ratio + Fusarium Oxysporium	Soil + Fusarium Oxysporium as Experimental Control

CONCLUSION
This study revealed that the bio–compost contained beneficial microbes and these microbes were able to improve growth of the ramets, reduce Fusarium wilt incidence and delay the progression of fusarium wilt.  Better banana growth and an almost disease free situation was observed in the 100 % bio–compost even when challenged with Foc R4. It was also revealed that the bio–compost has the potential to sequester the Foc R4 by forming an inhibition zone between the roots and Foc R4.  This may be due to the presence of high populations of beneficial microbes in the bio–compost which colonized the roots of banana ramets, thereby preventing Foc R4 from establishing colonies.