Pulvinaria psidii Maskell
Taxonomic placing: Insecta, Hemimetabola, Hemiptera, Sternorrhyncha, Coccoidea, Coccidae.
Common name: Guava scale; green shield scale.
Geographical distribution: East Africa, South-East Asia and Pacific islands, Hawaii, West Indian Islands and Florida, Egypt, Israel. CIE Map #59, 1994 (revised).
Host plants: As many as 250 plant species in 65 families, with a preference for plants with broad leaves.
Morphology: The body of the young female is flat, greenish, becoming darker as it begins to oviposit into a whitish ovisac, which may be quite long. The body reaches a length of 4.5 mm. The marginal setae are terminally expanded and fringed, and there are 3 spiracular setae, of which the median is the longest. The spiracles of adult females are surrounded by a sclerotized crescent, and the anal plates are triangular.
Life history: This thelytokous species completes three generations in Egypt.
Economic importance: The feeding of the pest causes two compounding types of damage on the plant: deriving the plant of nutrients and contaminating the leaves and fruit with sootymold that settles on the abundant honeydew. As a result the quantity and quality of the fruit (coffee, mango, guava) is much reduced,
Management
Chemical control: The pest can be controlled with organophosphates.
Biological control: Several hymenopterous endoparasitoids and entomopathogenic fungi were reported to attack the pest in other regions.
References
Abd-rabou, S. 2011. Field efficacy of parasitoid, Cccophagus scutellaris (Hymenoptera: Aphelinidae) and the predator, Exochomus flavipes (Coleoptera: Coccinellidae) against Pulvinaria psidii (Hymenopgtera: Coccidae) in Egypt. Journal of Biological Control 25:
Ben-Dov, Y. 2001. Pulvinaria psidii Maskell a new soft scale in Israel. Alon Ha’Notea 55: 262-263 (in Hebrew with an English Summary).
Easwaramoorthy, S. and Jayaraj, S. 1977. Control of guava scale, Pulvinaria psidii Mask., and chili aphid, Myzus persicae (Sulz.), with Cephalosporium lecanii Zimm. and insecticides. Indian Journal of Agricultural Science 43: 136-139.
Nada, S., Abd Rabo, S. And Hussein, G.E.D. 1990. Scale insects infesting mango trees in Egypt (Homoptera: Coccoidea). Proceedings of the Sixth International Symposium of Scale Insect Studies, pp. 133-134.
Williams, D.J. and Watson, G.W. 1990. The Scale Insects of the Tropical South Pacific Region. Part 3. The Soft Scales (Coccidae) and Other Families. CAB International, Wallingford, UK.
Websites
[http://www.extento.hawaii.edu/kbase/crop/Type/p_psidii.htm]