Tubang Bakod (Jatropha curcas) controls pest snail

Dr Abe V Rotor

Scientists Dr Domindo Tapiador of UN-FAO (left) and Dr AV Rotor examine Jatropa tree at the St Paul University Botanical Garden, QC. With them is Mr Dell H Grecia (center), veteran journalist and columnist of Women Journal.

The leaf extract of tubang bakod (Jatropha curcas) found growing wild on wastelands is effective in controlling golden or apple snail, Pomacea caniculata.

Ingestion of the bait prepared with one part of the crude extract with 10 parts rice bran (darak) resulted in sure death of the pest in both its immature and adult stages, thus preventing the pest from further destroying standing rice crop or spreading to nearby fields.

It will be recalled that the golden snail was introduced into the country in the seventies as supplemental food, but later turned maverick, and is now in the rank of pest, which includes stemborers and leafhoppers that attack rice and other crops.

The finding is traced to a thesis defended by Marie Shiela Alberto for a BS Biology degree at then St Paul College QC. Dr Anselmo S Cabigan, a well known biologist, and former director for research of the National Food Authority was the adviser.

Dr Cabigan emphasized the safe nature of botanical pesticides which are readily biodegradable, besides being practical in field application. Today some 2 million hectares of ricefields which harbor this pest stand to benefit from the result of this study.

Schistizomiasis Control

Jatropha curcas was also found effective in controlling the snail vector (Oncomelana quadrasi) of Schistozomiasis, a dreaded parasite that affects humans in tropical countries, the Philippines among the most affected. I had a chance to work in a project to drain and farm the fringes of the huge Sab-A Basin in Leyte. Various methods of controlling Schistozomiasis was conducted in consultation with the local Schistozomiasis Control Center headed by a certain Dr Blas. The vastness of the swamp needed a more extensive study to eradicate the snail and consequently the disease.

Direct Control Method

Here is a practical method I learned from farmers. Plant Jatropha on the high levees where it can grow into a small tree. Prune periodically the growing rice crop. Chopped and spread on the flooded field. Apply once or twice, on the early and late growing period of the crop. The biomass when decomposed will also serve as organic fertilizer.

NOTE: The plan to produce biofuel from Jatropha opens a potential source of natural pesticide. The active principle, although biodagradable, may be poisonous to other organisms, including fish, amphibians, beneficial insects, and the like. Toxicology studies should emphasize safety to humans and the environment as well.~