VARIATION IN LENGTH, FECUNDITY AND SURVIVAL OF PINK WAX SCALE, CEROPLASTES RUBENS MASKELL (HEMIPTERA, COCCIDAE), ON UMBRELLA TREES

We investigated some of the factors that may lead to outbreaks of pink wax scale, Ceroplastes rubens Maskell, on umbrella trees, Schefflera actinophylla (Endl.). Estimates of birth and death rates of pink wax s cale were high and variable within and among trees; variation in these rates was not related to scale density. Adult fecundity correlated si gnificantly but weakly with adult test length; mean fecundity was 292 eggs per female with a range of 5-1178. Adult test length and its vari ance decreased weakly with increasing density. Field experiments showe d that mortality of C. rubens is greatest during the first 24 hours af ter hatching when approximately half disappear. The rate of loss decre ases over time with 0.3% of initial motile first-instar nymphs survivi ng to maturity. Rates of loss varied significantly between trees, indi cating that some trees are more suitable for scale colonisation and su rvival.