Infestation estivale précoce des olives par Dacus oleae (Gmel.) (Diptera, Trypetidae) et rôle limitant du parasite Eupelmus urozonus Dalm. (Hymenoptera, Eupelmidae) dans une oliveraie grecque

Abstract

Population growth and population structure of natural populatzons of M. YOSUC 473 crowding on the expression of migratory urge among alatae in the laboratory. Ann. Appl. Biol.-1973: Effects of population density on alienicolae of Aphis fabae Scop. 11. The expression of SHAW, R. C.; P R A~A D , R., 1970: Starch gel electrophoresis of enzymesa compilation of recipes. TOMIUK, J.; WOHKMANN, K., 1979: Investigations on natural aphid populations. Proc. 1. TOMIUK, J.; WOHKMANN, K.; EGGERS-SCHUMACHER, H. A., 1979: Enzyme patterns as a charac-WOOL, D.; VAN EMDEN, H. F.; BUNTING, S. W., 1978: Electrophoretic detection of the internal 6J, 197-203. migratory urge among alatae in the field. Ann. Appl. Biol. 74, 1-7. Biochem. Gen. 4, 297-320. Mediteranean Congress of Genetics, Cairo. teristic for the identification of aphids. 2. ang. Ent. 88, 440446. parasite, Aphidius matricariae in Myzus persicae. Ann. Appl. Biol. 90, 21-26. AbstractEarly summer infestation of olive fruits by Dacus oleae (Gmel.) (Diptera, Ttypetidae) and its control by the parasite Eupelmus urozonus (Hymenoptera, Eupelmidae) in a greek olive groveThe analysis of the infestation rate of the fruits by D. oleae during summer was carried out in a typical and insecticide-free olive grove in Greece. The trees were generally poorly infested until1 the middle of September, then the infestation rate increased quickly during October and reached more than 80 % of the fruits at harvest time (table). When scanning the distribution of Daczisfield population, it is emphasized that just a few trees supported the summer multiplication of the flies. These "early sensitive trees" entertained in Jul an important number of preimaginal stages (fig. I), while more than 20 % of their fruits were inrested. They produced a first brood of adults which appeared in the McPhail traps during August (fi .2); then, a second one took place in September and its rogeny was responsible for the autumnaf attack. During the summer multiplication brood of the {ost, E. urozonus parasitized D. oleae as pupae, controlling up to 95.3 YO of the fly population by August 26'h (fig. 3).U.S.