PATTERNS OF PESTICIDE USE AND RESIDUE LEVELS IN EXPORTABLE PINEAPPLE (Ananas comosus L. Merr.)

EBENEZER ABOAGYE 134 PAGES (22363 WORDS) Entomology Thesis

ABSTRACT

Pesticide use pattern on exportable pineapple (Ananas comosus L. Merr.) (Smooth Cayenne) was studied in the Akwapim South District of Ghana through administration of questionnaires. Among the several pesticides listed as being used, only nine, representing 43%, had been provisionally approved for use on exportable pineapples. Farmers handled pesticides carelessly without necessary caution though they had general awareness of hazards of pesticides. Residue levels of chlorpyrifos and carbendazim in exportable pineapple (Smooth Cayenne) grown in the district were also determined using a Gas Chromatograph equipped with electron capture detector and Thin Layer Chromatography (TLC) by bioassay of Aspergillus niger Tiegh inhibition technique, respectively. The detection limit of carbendazim in the pineapple peel using TLC is 0.02|j.g/g. The carbendazim residue detected in the peel was in the range of 0.04±2xl0'2 to 0.05±lxl0‘2|ig/g. Chlorpyrifos was detected both in the peel and the pulp. The chlorpyrifos residue detected was within the range of 0.005±4.8xl0'3 to 0.02 ± lx l0 '2(ig/g. These levels of residue were below pesticide permissible levels established by the European Union. Regular monitoring of pesticide use and determination of residue levels are recommended to optimise the value of fresh pineapples and sustain the export potentials of the fruits.