Citrus tristeza virus (CTV) with 16–60 per cent incidence level is a major virus disease affecting almost all citrus varieties cultivated in Maharashtra. The transmission of CTV occurred through different species of aphid which colonized citrus plants during winter period of October-February. The minimum temperature of 10–14°C favoured the population build-up of aphid-vectors. Application of monocrotophos (0.05%) as foliar spray at 15 days interval during peak period of vector activity was found to be most effective treatment whereas alternate sprays of half dose of monocrotophos (0.025%) and neem oil (1%) also gave good control of aphid-vectors.
