Brachycaudus amygdalinus (Schouteden)]
Taxonomic placing: Insecta, Hemimetabola, Hemiptera, Sternorrhyncha, Aphidoidea, Aphididae.
Common name: Short-tailed almond aphid
Geographical distribution: Central and western Asia, eastern Africa and southern Europe.
Host plants: Almond, dock (Rumex spp.), horsetail knotweed (Polygonum equisetiforme Sm.).
Host plants: Almond, Rumex spp, horsetail knotweed (Polygonum equisetiforme Sm.).
Morphology: On almond the body of apterous females is dark- green, the siphunculi and cauda are very short, the antennae have six segments and body length is about 2 mm. On P. equisetiforme the body of such females is brown to dark green, the antennae have only five segments and the body is smaller. Alates have a black head and thorax and a green abdomen, their siphunculi and cauda are very short and body length is about 1.5 mm.
Life history: This aphid reproduces parthenogenetically throughout the year on horsetail knotweed. In autumn alate males and females migrate to almond trees, mate and lay eggs. The eggs hatch in the following spring, feed on the young foliage and reproduce by parthenogenesis. When their colonies become overcrowded winged forms appear and fly to P. equisetiforme, leaving almonds pest-free during summer.
Economic importance: The feeding on young almond leaves causes their curling and premature drop, twig growth is retarded and the internodes are shortened. In areas of the Eastern Mediterranean the pest causes severe damage to almonds.
Management
Chemical control: An early spring application of a systemic pesticide often controls this aphid.
Biological control: The almond aphid is attacked by several endoparasitoid Braconidae, like Ephedrus persicae Froggatt and by several Aphidiidae. Many predatory Coccinellidae, Anthocoridae and Miridae were associated with the pest in Syria. The anthocorid Anthocoris minki Dohrn attacks the aphid in Turkey. At times the pest is infected by the entomopathogenic fungus Erynia radicans Brefeld.
References
Almatni, W. and Khalil, N. 2008. A primary survey of aphid species on almond and peach, and natural enemies of Brachycaudus amygdalinus in As-Sweida, Southern Syria. In: Boos, Markus (ed.) Ecofruit - Proceedings of the 13th International Conference on Cultivation Technique and Phytopathological Problems in Organic Fruit-Growing, pp. 109-115.
Cohen, M. (ed.) 2000. A Guide to Integrated Pest Management of Stone Fruits in Israel. Pest Identification, Monitoring and Treatment Thresholds. Fruit Board of Israel (in Hebrew).
Ghorbali, R., Seyedoleslami, H., Rezwani, A. and Khajehali, J. 2008. Seasonal Population fluctuation of Brachycaudus amygdalinus (Schout.) and Hyalopterus amygdali (Blanch.) on almond trees in Najafabad region. Journal of Science and Technology of Agriculture and Natural Resources, Water and Soil Science 11: 249-259.
Swirski, E. and Amitai, S. 1999. Annotated list of aphids (Aphidoidea) in Israel. Israel Journal of Entomology 33: 1-120.
Talhouk, A.S. 1977. Contribution to the knowledge of almond pests in East Mediterranean countries. VI. The sap-sucking pests. Zeitschrift fur Angewandte Entomologie 83: 248-257>
Yanik, E. and Unlu, L. 2011. Biological traits and prey consumption of Anthocoris minki fed on Agonoscena pistaciae and Brachycaudus (Thuleaphis) amygdalinus. Phytoparasitica 39: 333-342.