Economical and less hazardous fungicide for the management of white root disease

Abstract

Rigidoporus lignosus, the causal agent of white root disease is the most destructive root pathogen of Hevea brasiliensis in Sri Lanka.presently 5-8% of the cultivated lands are affected with this deadly disease and are under bare patches. The recommended fungicides in Sri Lanka,Pentachloro nitrobenzene (PCNB)and Pentachloro phenol (PCP),were prohibited due to high mammalian toxicity and the fungicides of the triazole family which are being recommended in other countries such as Malayasia and Ivory Coast are not acceptable to Sri Lankan rubber growers due to the high costs of these chemicals. The observations of experiments carried out with less toxic chemicals revealed that 8-10% phenol in bituminous base could be used as an effective fungicidal "Collar protectant"in the management of white root disease in Sri Lanka.In this paper the econimics and the toxicological impact on the environment are also discussed.