Biology of Paracoccus Marginatus On Parthenium Hysterophorus

Abstract

The biology of Paracoccus marginatus William and Granara De Willink (Pseudococcidae: Hemiptera) when reared on Parthenium histerophorus L. revealed that its incubation period varied from 2 to 5 days and females had three nymphal instars. The first instar nymphal stage lasted for 6.44 days, and for second and third instars it was 6.30 and 5.72 days, respectively. The nymphs took 19 to 24 days in case of females (mean of 21.67 days). In case of male it was four nymphal instars with two nymphal instars besides an additional pre-pupal and pupal stages; first and second instar lasted for 6.44 and 7.01 days, respectively. For both male and female, the developmental time was accounted separately from second instar onwards. Crawlers developing into male differentiated in second instar, and it was indicated by change in colour from greenish yellow to slight pink. These took 17 to 22 days for developing (mean 19.3 days), due to additional pupal stage. The adult longevity in male ranged 2 to 4 (2.58 ± 0.39) days. The total developmental period in female was from 41 to 65 (61.5 ± 3.26) days, while in male it was 24 to 35 (31.3 ± 5.87) days. The morphometrics of egg, nymphal instars, pupae and adults for both male and female had also been studied. The eggs were greenish yellow to green and are laid in an egg sac which is 2–3 times bigger than the body length and entirely covered with white cottony wax secretion produced by female.