Brachycaudus schwartzi (Börner)
Taxonomic placing: Insecta, Hemimetabola, Hemiptera, Sternorrhyncha, Aphidoidea, Aphididae.
Common name: Peach curl aphid.
Geographical distribution: Mediterranean basin, Russia to India, South America, California, New Zealand. In the Middle East the pest reported since the early 1990’s.
Host plants: Various stone fruits, especially peaches, plums and nectarine (Prunus persica Siebold and Zuccarini)).
Morphology: The body of apterous females is yellow-brown, 1.6-2.0 mm long. The cauda, siphunculi and parts of the abdomen are dark-brown. The alate females, including the cauda and siphunculi, are mostly brown, except for the yellow abdomen. Body length is 1.5-1.9 mm.
Life cycle: The apterous females reproduce by viviparous parthenogenesis oon Prunus during autumn and early winter, but its host(s) have not yet been determined in this region. A generation is completed in one week at 25ºC and a viviparous female produces about 45 progeny. The threshold of development was calculated to be 10.0ºC, and about 103 day degrees are necessary to complete a generation. This aphid is very sensitive to temperatures above 27ºC and low air humidity. The pest is often attended by ants that apparently protect it from natural enemies.
Economic importance: The feeding of B. schwartzii causes severe curling of peach leaves, disrupts bud development and young infested fruit may drop. This pest is nowadays the dominant aphid on peaches. Due to its better development at lower temperatures, early season peach or nectarine varieties are more susceptible. The peach curl aphid can transmit the Plum pox virus (PPV), which causes the sharka disease, an important disease of peaches. In Italy that has led to obligatory eradication of infected peach trees.
Management
Chemical control: This pest is susceptible to organophosphates that may be applied as needed.
Biological control: This aphid is attacked by predators of the families Cecidomyiidae, (like Aphidoletes aphidomyza Rondani,) Coccinellidae (especially Scymnus (Pullus) argentinicus (Weise)) and Syrphidae (like Allograpta neotropica Curran), and by endoparasitoids of the family Aphidiidae, like Aphidius colemani Viereck. The pest is also infected by the entomopathogenic fungus Erynia neoaphidis Remaudière and Hennebert. The combined effect of these natural enemies on the pest is not known,
References
Auad, A.M. Bueno, V.H.P. Kato, C.M. and Gamara, D.C. 1997.Occurrence and population fluctuation of predators and parasitods of Brachycaudus (Appelia) schwartzi (Börner) (Homoptera: Aphididae) on peach trees, in Jacuí, MG. Anais de Sociedade Entomologica do Brasil 26: 257-263.
Halima-Kamel, M.B. and Karboul, H. 2014. Brachycaudus schwartzi Börner, un nouveau ravageur sur pêcher et prunier en Tunisie. EPPO Bulletin 44: 57–59.
Manachini, B., Cassati, P., Aliverti, I. and Cinanni, L. 2004. Transmission of PPV-M to Prunus persica by Brachycaudus schwartzi and Phorodon humuli (Hem., Aphididae). Journal of Applied Entomology 128: 677-680.
Satar, S. and Yokomi, R. 2002. Effect of temperature and host on development of Brachycaudus schwartzi (Homoptera: Aphididae). Annals of the Entomological Society of America 95: 597-602.
Shofet, M. and Swirski, E. 1997. The peach aphid, Brachycaudus (Appelia) schwartzii (Börner), a new pest in stone-fruit orchards of Israel. Alon Ha’Notea 51: 298-303 (in Hebrew with an English Abstract).
Swirski, E. and Amitai, S. 1999. Annotated list of aphids (Aphidoidea) in Israel. Israel Journal of Entomology 33: 1-120.