Abstract
In house type godowns, bag cum bulk storage of wheat is common in Pakistan Agricultural Storage and Services C(';poration (PASSCD). For protection of stored wheat in these godowns, Phosphine fumigation is always done by using aluminium phosphide (AlP) tablets. In this practice total number of tablets are scattered around and on the surface of the stack. This method was tested and proved to be ineffective because of insufficient penetration and retention of phosphine gas in deeper zones of the stack. To improve upon phosphine fumigation two other methods (multiple and dosing pipe application methods) were tested. In multiple application method a higher dose rate was used in two successive applications while in dosing pipe method, perforated PVC pipes were used in the bulk wheat to apply the AlP tablets. Out of these three methods, dosing pipe method proved to be the most effective and resulted in to better retention and distribution of phosphine gas in different zones of the bulk wheat.
