Population dynamic of Diclidophlebia irvingiae, Burckhardt et al. (Hemiptera: Psylloidea), psyllid pest of Irvingia gabonensis Baill (Irvingiaceae, Rutales) in Bamenda, North-West region of Cameroon

Diclidophlebia irvingiae is a sap-sucking insect of Irvingia gabonensis inducing important damage to its host plant which has medicinal and nutritional importance in Africa particularly in Cameroon. The aim of the survey was to study numerical variation of the pest during the year and impact of biotic and abiotic factors on numerical variation. The study was carried in Bamenda from March 2018 to March 2019 where larvae and adults of D. irvingiae were collected monthly. The study permitted us to record 3290 individuals 1341 males, 1396 females and 553 larvae. Population fluctuation of the pest during the year showed five periods of individual outbreak corresponding to the generation number of the pest. As most tropical and sub-tropical psyllid species D. irvingiae is a multivoltine species with five annual generations. The outbreak periods depend principally on the phenology of host plant. The statistical test showed that the numerical individual variation of D. irvingiae is not directly related to climatic factors because they do not show significant probability.Keywords: Impact, Biotic, Abiotic, Factors, Insect, Faunistic.