Phenology, biological and cultural control of the new almond pest Eurytoma amygdali (Hymenoptera, Eurytomidae) in Spain
Abstract
Aim of study: Eurytoma amygdali Enderlein (Hymenoptera, Eurytomidae), the almond wasp, is a new pest detected in Spain. Although the insect is present in Europe, in Spain no damage was detected until 2016, increasing substantially in the following years. The phenology of almond wasp and the natural enemies complex were investigated and the results of the parasitism rate and cultural control measures were analyzed.
Area of study: Five Spanish provinces, important regions for almond production where E. amygdali causes serious harvest losses.
Material and methods: Samples of different almond varieties were taken from ecological almond plots in the Spanish provinces of Valencia, Alicante, Albacete, Murcia and Cuenca.
Main results: The first almond wasp eggs were observed at the beginning of May and completely developed larvae, early in July. Wasp flight occurred from mid-March to late May. Two natural enemies were associated with the pest, Pyemotes amygdali Çobanoğlu & Doğanlar (Acari, Pyemotidae), and Opilo domesticus (Sturm) (Coleoptera, Cleridae). Pyemotes amygdali parasitized wasp larvae, adult females and males, and Opilio domesticus fed on wasp larvae. O. domesticus was very scarce, unlike P. amygdali. In the plots with parasitized wasps, the parasitism rate ranged from 0.6% to 44% for P. amygdali.
Our results suggest that sanitation measure was an important cultural pest control practice, because in the plantations where mummified almonds were removed, 96% of edible almonds were harvested, compared to 18% if mummified almonds were not removed from trees.
Research highlights: Cultural control could be an important measure to control the almond wasp, because it allows biological conservation control, by preserving natural enemies present in the environment and avoid the negative effect of insecticides.
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References
Abdul-Rassoul MS, Mohammed SM, 2017. First record of Adontomerus amygdali (Boucek, 1958) (Hymenoptera, Torymidae): a parasitoid of the almond fruit wasp, Eurytoma amygdali Enderlein, 1907 (Hymenoptera, Eurytomidae) in Erbil Provence, IRAQ. Bull Iraq nat His Mus 14: 301-306. https://doi.org/10.26842/binhm.7.2017.14.4.0301
Bahillo de la Puebla P, López Colón JI, 2000. El género Opilo Latreille, 1802 en la Península Ibérica (Coleóptera, Cleridae) Boln Asoc esp Ent 24: 213-227.
Bahillo de la Puebla P, López Colón JI, Prieto Piloña F, 2021. La familia Cleridae Latreille, 1802 (Coleoptera) en la Península Ibérica e Islas Baleares. A E 23: 3-98
Cakar L, 1980. Eurytoma amygdali End. (Hym., Chalcidoidea, Eurytomidae) a pest of almond in Macedonia. Zastita Bilja, 31, 263-272. (in Bosnian with French abstract)
Cioacă L, Ciceoi R, Stănică F, 2022. Almond seed wasp, Eurytoma amygdali, a new fruit pest in the romanian fauna. Scientific Papers. Series B, Horticulture 66: 34-39.
Çobanoğlu S, Doğanlar M, 2006. A new Pyemotes (Acari: Pyemotidae) reared from larvae of the Almond Seed Wasp, Eurytoma amygdali (Hymenoptera: Eurytomidae) from Hatay, Turkey. Zool Middle East 39: 101-106. https://doi.org/10.1080/09397140.2006.10638189
Correa De Barros JM, 1929. Notas para o estudo das espécies da Fam. Cleridae existentes em Portugal. Arquivos da secçáo de Biología e Parasitologia do Museo da universidade da Coimbra 1, 1-25.
Doğanlar O, Emin Yıldırım A, Doğanlar M, 2006. Natural Enemy Complex of Eurytoma Amygdali Enderlein, 1907 (Hymenoptera, Eurytomidae) in Eastern Mediterranean Region of Turkey; Notes on Their Interaction and Effectiveness. Res J Agric & Biol Sci 2: 282-286.
Español F, 1959. Los Cléridos (Cleridae)de Cataluña e Islas Baleares (Col., Cleroidea). Publicaciones del Instituto de Biología Aplicada Barcelona 30, 105-146
Gauss R, 1954. Der Ameisenbuntkafer Thanasimus (Clerus) formicarius Latr. als Borkenkaferfeind. In. Die Grosse Borkenkaferkalamitat in Südwest-Deutschland J944-5J. G. Wellenstein [Ed.]. Ulm.
Gerstmeier R, 1998. Checkered Beetles: Illustrated Key to the Cleridae and Thanerocleridae of the Western Palaearctic Buntkäfer: Illlustrierter Schlüssel zu den Cleridae und Thanerocleridae der West-Paläarktis. Magraf publishers, Weikersheim, Baden-Württemberg, 241 pp, 8 col plates, 304 text figs, maps.
Haustein T, Busweiler S, Haustein V, von Laar C, Plarre R, 2019. Laboratory breeding of Korynetes caeruleus (Coleoptera: Cleridae) for the biological control of Anobium punctatum (Coleoptera: Ptinidae). Eur J Entomol 116: 362–371. https://doi.org/10.14411/eje.2019.038
Ibrahim MY, Al-Fouzoo T, Al-Naser Z, 2008. Biological and ecological studies of almond fruit wasp, Eurytoma amygdali End. (Hymenoptera: Eurytomidae) at Homs Governorate (Syria). JJAS 4(1): 139-151.
Katsoyannos BI, Kouloussis NA, Bassiliou A, 1992. Monitoring populations of the almond seed wasp, Eurytoma amygdali, with sex pheromone traps and other means, and optimal timing of chemical control. Entomol Exp Appl 62: 9-16. https://doi.org/10.1111/j.1570-7458.1992.tb00635.x
Margaritopoulos JT, Tzanakakis ME, 2006. Diapause completion in the almond seed wasp, Eurytoma amygdali (Hymenoptera: Eurytomidae) following early low temperature treatment. Eur J Entomol 103: 733–742. https://doi.org/10.14411/eje.2006.097
Mentjelos J, Atjemis A, 1970. Studies on the Biology and Control of Eurytoma amygdali in Greece. J Econ Entomol 63: 1934-1936. https://doi.org/10.1093/jee/63.6.1934
Noyes JS, 2019. Universal Chalcidoidea Database. World Wide Web electronic publication. http://www.nhm.ac.uk/chalcidoids (accessed June 2023).
OEPP/EPPO 2004, Bulletin OEPP/EPPO Bulletin 34, 427–438. Stone fruits. https://doi.org/10.1111/j.1365-2338.2004.00750.x
Plaut HN, 1971a. Behaviour of phosphamidon within the young almond fruit, and action of translocated phosphamidon and monocrotophos on the egg and the young larva of almond wasp Eurytoma amygdali. Pestic Sci 2: 113-114. https://doi.org/10.1002/ps.2780020305
Plaut HN, 1971b. On the biology of adult of almond wasp, Eurytoma-amygdali End (Hym, Eurytomidae), in Israel. B Entomol Res 61: 275-281. https://doi.org/10.1017/S0007485300057795
Plaut HN, 1972. On the biology of the immatures stages of the almond wasp, Eurytoma amygadali End (Hym. Eurytomidae) in Israel. B Entomol Res 61: 681-687. https://doi.org/10.1017/S0007485300047519
Saeidi Z, 2021. Resistance of different almond cultivars/genotypes to almond fruit wasp, Eurytoma amygdali (Hymenoptera: Eurytomidae). J Crop Prot 10(3): 535-545.
Schäckermann J, Pufal G, Mandelik Y, Klein AM, 2015. Agro-ecosystem services and dis-services in almond orchards are differentially influenced by the surrounding landscape. Ecol Entomol 40: 12-21. https://doi.org/10.1111/een.12244
Schroeder LM, 1999. Prolonged development time of the bark beetle predator Thanasimus formicarius (Col.: Cleridae) in relation to its prey species Tomicus piniperda (L.) and lps typographus (L.) (Col.: Scolytidae). Agr Forest Entomol 1: 127-35. https://doi.org/10.1046/j.1461-9563.1999.00018.x
Talhouk AS, 1977. Contributions to the knowledge of almond pests in East Mediterranean countries V. The fruit-feeding, Eurytoma amygdali End., and Anarsia lineatella Z. Z Angew Entomol 83: 145-154. https://doi.org/10.1111/j.1439-0418.1977.tb02384.x
Tolga M, Yoldaş A, Zeynep Y, 2018. Investigation on the damage rate of Eurytoma amygdali Enderlin (Hymenoptera: Eurytomidae) with first record of its parasitoid, Exeristes roborator (Fabricus) in almond orchards of Mugla and Manisa. Türkiye VII. Bitki Koruma Kongresi (Uluslararas1 Kat1hmh), 14-17 Kas1m 2018, Mugla, Türkiye.
Tzanakakis ME, Papadopoulos NT, Katsoyannos BI, Drakos GN, Manolakis E, 1997. Premature fruit drop caused by Eurytoma amygdali (Hymenoptera: Eurytomidae) on three almond varieties. J Econ Entomol 90: 1635-1640. https://doi.org/10.1093/jee/90.6.1635
Tzanakakis ME, Veerman A, 1994. Effect of temperature on the termination of diapause in the univoltine almond seed wasp Eurytoma amygdali. Entomol Exp Appl 70: 27-39. https://doi.org/10.1111/j.1570-7458.1994.tb01756.x
Yiğit T, Özgen İ, Canbay A, Koç İ, 2020. Infestation rate of almond seed wasp (Eurytoma amygdali Enderlein, Hymenoptera: Eurytomidae) on important commercial almond varieties in Malatya province (Turkey). I J I E A 4: 9-12. https://doi.org/10.46460/ijiea.737755
Zerova MD, Fursov VN, 1991. The Palaearctic species of Eurytoma (Hymenoptera: Eurytomidae) developing in stone fruits (Rosaceae: Prunoideae). B Entomol Res 81: 209-219. https://doi.org/10.1017/S0007485300051294
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