|Authors: ||M.J. Leandro, M. Oliveira, A.M. Passarinho, E. Figueiredo, J.C. Franco, J. Neves-Martins, A. Mexia|
|Keywords: ||Proteaceae, mealybugs, Anagyrus pseudococci, Leptomastix dactylopii, biological control|
Delottococcus confusus and Paracoccus spp. (Pseudococcidae) have been identified as key pests in Protea cynaroides, Protea var ‘Susara’ and Leucospermum var ‘Scarlet Ribbon’ and ‘High Gold’ in the SW of Portugal.
Chemical control of these pests, with the available products, has proven very difficult.
Consequently, biological control was tested with the introduction of Cryptolaemus montrouzieri (Coccinellidae). Although good results were obtained in the Leucospermum varieties and in Protea var ‘Susara’, the ladybird proved totally inefficient in Protea cynaroides. It was then decided to test two parasitic wasps Leptomastix dactylopii and Anagyrus pseudococci. The parasitism capacity of these two species was assessed in the laboratory between November 2004 and August 2005. For A. pseudococci twenty blocks of two pot plants of Leucospermum var. ‘Scarlet Ribbon’ infested with mealybugs of both species were used.
In each repetition, 90 mealybugs were dissected to determine the parasitism rate and the encapsulation rate.
For L. dactylopii the experiment was conducted in a similar way but using only ten blocks of one pot plant and observing 80 mealybugs in each repetition.
The parasitism rate varied between 18.2% and 55.1% for A. pseudococci and between 34.1 % and 45.6 % for L. dactylopii. The encapsulation rate was zero for this last species and 7.6% for A. pseudococci.
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