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Pests of Apple :: Major Pest :: San Jose Scale


2.  San Jose scale: Quadraspidiotus perniciosus (Diaspididae: Hemiptera)

Distribution and status: Kashmir, Himachal Pradesh and Tamil Nadu
Host range: Cherry, plum, pear, peach and most other temperate fruit trees


Damage symptoms



Due to sap sucking by nymphs and adults the infested bark becomes reddish pink, purple colouration in fruits.




Overwintering nymphs become active in mid March and the males emerge in April. Females are ovo-viviparous and reproduce in mid May producing 200-400 nymphs in a month, nymphal period 20 days. Life cycle completed in 35-40 days.  4-5 generations completed before hibernation which starts in mid October. Insects begin to grow during bloom period. Female scale is round slightly convex with a black pustule and the male is linear. 



Regularly prune the infested branches and burn them.
Release the parasite Encarsia perniciosi to check the over wintering population.
Spray diazion 20 EC 3.75 L or methyl demeton 25 EC 2.0 L in 1500 – 2000 L of water per ha in case of severe scale infestation.
Apply carbofuran 3 G @ 20 - 30 g /plant in nursery.