POST-HARVEST FUMIGATION OF TUBERS FOR THE CONTROL OF SWEET POTATO WEEVIL

Abstract

The use of ethylene dibromide (EDB) and phostoxin in controlling sweet potato weevil was evaluated. Larvae and pupae were effectively controlled when EDB was used at the rate of 32 ml/cu m. However, phostoxin at 10.5 tablets/cu m was more effective than EDB in controlling the different developmental stages of the weevil. This showed the greater potential of phostoxin in controlling the pest aside from its superior characteristics as compared to that of EDB. Phostoxin is less toxic (LD50 = 50 ppm) than EDB (LD50 = 20 ppm), and is easier to apply, hence, an inexpensive fumigation chamber could readily be rigged up in rural areas utilizing this fumigant.