Lysiphlebus testaceipes (Cresson) (= L. t.) has been introduced from Cuba (via Czechoslovakia) to Southern France in 1973/74 to control the exotic aphids Toxoptera aurantii (B.d.F.) and Aphis citricola v. d. G. on Citrus. Research until 1986 showed that L. t. had established over the whole of Mediterranean France (as well as Spain, Portugal, and most of Italy to Sicily). Apart of high effectiveness on the target species (incomplete parasitism on A. citricola) L.t. has become the predominant parasitoid of a number of indigenous pest aphids and indifferent species in all environments from agroecosystems to climax ecosystems (forests). Oligophagy of L. t. is considered rather useful due to the phenology of its particular host species that manifest considerable seasonal succession. The effectiveness of L. t. as well as the value of the biocontrol project for the whole Mediterranean area are discussed. Zusammenfassung Biologische Schädlingskontrolle von Läusen im Mittelmeergebiet Frankreichs mit dem eingeführten Parasitoiden Lysiphlebus testaceipes (Cress.) (Hym., Aphidiidae) Lysiphlebus testaceipes (= L. t.) wurde in den Jahren 1973/74 von Kuba über die Tschechoslowakei nach Südfrankreich eingeführt, um die nicht heimischen Läuse Toxoptera aurantii (B. d. F.) und Aphis citricola v. d. G. zu bekämpfen. Die Untersuchungen bis 1986 zeigten, daß L. t. sowohl im gesamten Mittelmeergebiet Frankreichs als auch in Spanien, Portugal und großen Teilen Italiens und Siziliens erfolgreich angesiedelt werden konnte. Neben der hohen Wirksamkeit gegen die Zielschädlinge (unvollständige Parasitierung von A. citricola) entwickelte sich L. t. zum wichtigsten Parasitoiden bei einer Anzahl einheimischer, sowohl schädlicher als auch indifferenter Läusearten. L. t. tritt inzwischen in allen Vegetationsformen auf, vom landwirtschaftlichen bis zum forstwirtschaftlichen Ökosystem. Im Hinblick auf die Phänologie seiner Wirte erwies sich die Oligophagie von L. t. als sehr günstig. Es werden sowohl die Wirksamkeit von L. t. als auch die Bedeutung dieses Projekts für die biologische Schädlingsbekämpfung im Mittelmeerraum diskutiert.

Five subspecies of Bacillus thuringiensis were isolated from dead and diseased larvae obtained from a laboratory colony of the European sunflower moth, Homoeosoma nebulella. The subspecies isolated were B. thuringiensis subspp. thuringiensis (H 1a), kurstaki (H 3a3b3c), aizawai (H 7), morrisoni (H 8a8b), and thompsoni (H 12). Most isolates produced typical bipyramidal crystals, but the B. thuringiensis subsp. thuringiensis isolate produced spherical crystals and the B. thuringiensis subsp. thompsoni isolate produced a pyramidal crystal. Analysis of the parasporal crystals by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the crystals from the B. thuringiensis subsp. kurstaki and aizawai isolates contained a protein of 138 kDa whereas those from B. thuringiensis subsp. morrisoni contained a protein of 145 kDa. The crystals from B. thuringiensis subsp. thuringiensis contained proteins of 125, 128, and 138 kDa, whereas those from B. thuringiensis subsp. thompsoni were the most unusual, containing proteins of 37 and 42 kDa. Bioassays of purified crystals conducted against second-instar larvae of H. nebulella showed that the isolates of B. thuringiensis subspp. aizawai, kurstaki, and thuringiensis were the most toxic, with 50% lethal concentrations (LC 50 s) of 0.15, 0.17, and 0.26 g/ml, respectively. The isolates of B. thuringiensis subspp. morrisoni and thompsoni had LC 50 s of 2.62 and 37.5 g/ml, respectively. These results show that a single insect species can simultaneously host and be affected by a variety of subspecies of B. thuringiensis producing different insecticidal proteins.

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Aceria tulipae (K.) is responsible for important crop losses of garlic in all production areas around the world. However, very little is known about its development in relation to temperature and relative humidity (r.h). Laboratory rearings from egg to adult stage were done on pieces of the apical part of young garlic leaves. These leaf pieces were placed in aluminium dishes floating on water or put on a solid hygroscopic salt in closed plastic trays. Rearing done in dark incubators at constant temperatures (10°C to 458C) and with different r.h (25% to 75%) at 15°C and 258C showed that: i) the shortest development time occurs at about 258C; ii) the upper lethal temperature and the development threshold for the eggs are respectively estimated about 458C and 68C; iii) a r.h close to 100% is required for a high percentage of egg hatching, but water condensation on leaves is harmful. Host transpiration has an important regulatory effect on humidity conditions favouring mite survival. E E Lindquist, M W Sabelis and J Bruin. World Crop Pests 6. Elsevier Science BV. Pop I. 1961. Die Strichelvirose des Weisens in der Rumänischen Volksrepublik. Phytopathology Zeitung 43:325-336. Razvyazkina G M. 1966. Biology and feeding specializations of grass mites of the family Eriophyidae. In Trudi V Vse-Soyuzniy Sovyeshchaniye po virusnim boleznyam rastenii [The Works of