PAPER TITLE :LETHAL EFFECTS OF SULFURYL FLUORIDE (SF) TO DEVELOPMENTAL STAGES OF TWO CALLOSOBRUCHUS SPECIES (COLE

JOURNAL Of SUSTAINABLE TECHNOLOGY | VOLUME 3 NUMBER 2 2012

Paper Details

  • Author(s) : OFUYA, T.I. REICHMUTH, C., KLEMENTZ, D., ADLER, C. and ADARKWAH, C
  • Abstract:

The mortality and sub-lethal responses of developmental stages of Callosobruchus maculatus Fabricius and C. subinnotatus Pic. after fumigation with sulfuryl fluoride (SF) were observed under controlled conditions (25° and 30° C and 60-70% r.h.). Five SF concentrations (range, 3.1 – 20.3 g/m3) and six exposure periods (range, 0-24 hours) were involved. Eggs, larvae, pupae and adults of the bruchids were fumigated in gastight dressel flasks and SF concentrations were determined with aid of a Fourier transform infrared spectroscope. The eggs of C. maculatus and C. subinnotatus were more tolerant to SF than the adults, larvae and pupae which were all killed by fumigation with 10.2 g/m3 of SF at 30° C in 24 hours. Complete mortality of adults, larvae and pupae of the two bruchid species was achieved with 3.1 g/m3 or more of SF at 25° C. Adults of bruchids were killed with 3.1 g/m3 SF in 4 hours at 30° C. The developmental period (egg to adult) of fumigated bruchid eggs was significantly longer than for those that were not fumigated, by 2 to 4 days. Adult bruchids which survived direct sub-lethal exposure to fumigation with 3.1 g/m3 SF laid significantly fewer eggs than those that were not exposed to fumigant. Adults that emerged from fumigated bruchid eggs laid as many eggs (P > 0.05) as those emerging from the eggs which were not fumigated.