Fecundity, fertility and phenology of white wax scale, Ceroplastes destructor Newstead (Hemiptera: Coccidae), on Citrus and Syzygium in South Africa
The population density of Ceroplastes destructor Newstead has increased steadily since 1994, particularly on Citrus reticulata (Blanco), in citrus-growing areas of the Western and Eastern Cape Provinces of South Africa. The fecundity, body size and phenology of C. destructor were studied to provide a more informed basis for control programmes. No significant differences in fecundity were found between orchards (P > 0.05). However, fecundity varied significantly between female size-classes from the same orchard (P < 0.001). Female body-size differed significantly between orchards (P < 0.05) and was significantly positively correlated with fecundity both in 1997 and 1998. Different size-groups had varying oviposition periods, larger individuals having a longer oviposition period. No differences in egg fertility were found between orchards (P > 0.05). Ceroplastes destructor had one generation per year in the Western Cape Province, South Africa. Oviposition commences in mid November and continues until the end of December, with a few females ovipositing until mid January. The decline in population density of the second instar in February was followed by a steady increase in that of the third instar. The third instar stage extended to the end of July followed by a peak population of adults in August.