Reza, M.W., & Ghatak, S.S. 2006 Bio-efficacy of some commercial organic formulations against guava scale insect, Pulvinaria psidii Maskell (Coccidae: Hemiptera).. Environment & Ecology 24(2): 327-331.

Notes: The bio-efficacy of two commercial organic formulations neem spray Aza-3000 EC and DC tron-plus, a petroleum product, was evaluated against guava scale insect Pulvinaria psidii [Chloropulvinaria psidii] at a farmer's field in Ghoragachha village in Nadia, West Bengal, India, and compared to Metasystox [demeton-S-methyl] 25 EC widely used by guava farmers to suppress populations of the same pest. Both neem spray Aza-3000 EC and DC tron-plus were given at 2.0, 3.0 and 4.0 ml/litre of water, while Metasystox 25 EC was given at 1.0, 1.5 and 2.0 ml/litre of water. Befitting with the pest activity, two rounds of sprayings with all the formulations were given, i.e. one on 8 May 2004 and the other on 24 May 2004. Neem spray Aza-3000 EC and DC tron-plus at all rates were as effective as Metasystox 25 EC, producing a remarkable reduction in the population buildup of P. psidii (82.00-93.00%) over the control at 10 days after sowing (DAS). Sooty mould, which developed on the leaves due to the secretion of honeydew by the scale insect, was also eliminated after 7-10 DAS with these two organic formulations. Hence, neem spray Aza-3000 EC and DC tron-plus at 2-3 ml/litre of water may be appropriate for the protection against P. psidii.