LIFE HISTORY AND REPRODUCTIVE PHYSIOLOGY OF CITRUS MEALYBUG,PLANOCOCCUS CITRI (RISSO) (HEMIPTERA: PSEUDOCOCCIDAE) ON DIFFERENT HOST PLANTS

摘要

Host plant quality determines the development,fecundity and survival of herbivorous insects that directly impacts their survival and developmental success.Most insect prefer a few food plants for better development,longevity and their reproduction.Life history studies of P.citri,an emerging insect pest problem in Pakistan,was conducted under controlled laboratory conditions for four different host plants viz.,citrus,guava,grapes and ornamental China rose.Female mealybugs required more developmental duration (days) than male mealybugs.Citrus was the most favored with the shortest total nymph duration for both sexes (27.2±0.87 days for male,30.4±0.48 days for female.However,it was the longest (30.4± 1.17 for male,36.4±0.51 days for female) on guava,P.guajava and grapes,V.vinifera (30.7±1.30 days for male,37.6±0.46 days for female),respectively.Pre-oviposition (10.4±0.40 days),oviposition (3.15±0.21days) and post-oviposition (2.25± 0.45days) durations were also shorter on citrus,C.reticulate with maximum egg hatching percentage (88.6% ± 3.2) insignificant with China rose,H.rosa-chinensis (85.03%±2.78).From biological and fecundity parameters of P.citri,C.reticulate and H.rosa-chinensis were more preferred hosts than P.guajava and V.vinifera.This implies multiple suggestions for their intercropping with biocontrol program,suitable hosts for rearing and more careful and timely surveillance in citrus for its effective and long term management.