Fumigants and their Use

 

Aluminium phosphide

Aluminium phosphide can be used for fumigating rat burrows and for control of pests infesting stored grains. This is available as 'Celphos' or as 'Aluminium Phosphide' tablets (3g) or pellets. For rat control, locate the burrows, which contain live rats. For this, seal all burrow openings with mud in evenings and examine the closed burrows next day. If the mud seal is opened, such burrows are marked as live ones. In such live burrows, introduce aluminium phosphide tablets @ 1-2 per burrow and seal off the openings immediately. For fumigating grains and grain products under cover, use aluminium phosphide @ 1-2 tablets per tonne of grains, giving an exposure period of 5 days followed by aeration for a day. For room fumigation, use 5-7 tablets for every 28 cubic metre storage space. This has to be used under strict supervision of the approved pest control operators.

Methyl bromide This is a colourless gas at room temperature. Liquefied gas is available in steel cylinders or in 20 cc ampoules. This is used to fumigate soil required to raise rooted cuttings of pepper. For this, the recommended dose is 500 g/t of soil. The fumigant is exposed under tarpaulin covers for a period of 4-5 days to control the nematodes. Methyl bromide is also used to fumigate plants, grains and grain products. For grain fumigation, the suggested dose is 450-675 g (262-400 ml) for 28 cubic metre space. The period of exposure should be one day, the aeration being given for 4-6 hours. This has to be used under expert supervision by authorized officials.
ED/CT  This is a mixture of ethylene dichloride and carbon tetrachloride in the ratio of 3:1 by volume. This is soluble in fats and oils and therefore not recommended for fumigating oil seeds or copra. For cover fumigation, the suggested dose is 150 g (120 cc) per m3 (4 kg per 28 m3).
References Kerala Agricultural University. 2011. Package of Practices Recommendations: Crops.14th edition. Kerala Agricultural University, Thrissur- 360 p.