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Efficacy of Scutellista cyanea Motsch. on the soft scales, Saissetia coffeae Wlk., S. oleae (Bern.) and Ceroplastes floridensis Comst. was measured by monthly sampling of hosts in two locations. S. cyanea was prevalent on S. coffeae and S. oleae from August to November and on C. floridensis in March and September. Percentage of parasitized adult females of S. coffeae reached its peak in Abou-Hommos location (70.7%) (South East Alexandria) and in Alexandria (25%) during October, 1974. In 1972 and 1973, parasitized adults were 36.1% and 43.2%, in Alexandria during August and September, respectively. The population density of the parasite was affected by the number of adult host females and weather condition. From November to the first of April, scarcity of gravid adult scales of S. coffeae decreased the population density of the parasite. Accordingly, the parasite needed long time during summer to accomplish high parasitization in autumn. In the case of S. oleae and C. floridensis the abundance of the parasite was conjoint with the preferred stage of host which occurred during winter season. Zusammenfassung Zur Wirksamkeit von Scutellista cyanea Motsch. (Hym., Pteromalidae) gegenuber den Schildlausen Saissetia coffeae Wlk., S. oleae (Bern.) und Ceroplastes floridensis Comst. (Hom., Coccidae) Die Chalcidide S. cyanea parasitierte die beiden Saissetia-Arten zwischen August und November sowie die 3. Art, C. floridensis, im Marz und September. Die hochste Parasitierungsquote bei den adulten S. coffeae wurde bei Abou-Hommos mit 70.7% und bei Alexandria mit 25.0% im Oktober 1974 erreicht. 1972 und 1973 wurden die Maxima bereits im August/September mit 36,1% und 43,2% registriert. Die Parasitendichte wurde von der Zahl der adulten Wirtsweibchen sowie den Witterungsverhaltnissen beeinflust. Vom November bis April druckte der Mangel an adulten Schildlausen von S. cyanea die Parasitendichte herunter. Demgemas benotigte der Parasit eine langere Zeit wahrend des Sommers, um wieder hohere Dichte zu erreichen. Bei den Schildlausen S. oleae und C. floridensis war die Dichte des Parasiten korreliert mit dem bevorzugten Wirtsstadium, das erst wahrend der Wintersaison zur Verfugung stand.

The bionomy of Scutellista cyanea Motsch. was carried out for three generations from September, 1974 until February, 1975, under laboratory conditions. Cucurbita spp. fruits were used for rearing the host soft scale Saissetia coffeae Wlk. Virgin females of the latter were transferred into small glass tubes in which they fixed themselves and facilitated biological observation. The life span of the adult Pteromalid showed a contradicting picture with variation of temperature when compared with the immature developmental stages of larvae and pupae, since the low temperature exhibited short duration period of adults. Each of the Pteromalid larvae consumed 83 % of all deposited host eggs in average. Under temporary superparasitism condition, the two parasitic larvae consumed 98.3 % of eggs. In the latter case, 83.7 % of this parasite were males. Also, in the field the males were dominant, being 58.3 % and 52 %, during November and December, respectively. Zusammenfassung Zur Biologie der Schlupfwespe Scutellista cyanea Motsch. Es wurden Laboruntersuchungen uber die Bionomie von S. cyanea 1974/75 wahrend dreier Generationen der Schlupfwespe durchgefuhrt. Als Wirt diente die Schildlaus Saissetia coffeae Wlk. an Cucurbita-Fruchiten. Die Lebensdauer der adulten Schlupfwespe in Beziehung zur Temperatur ergab ein widerspruchliches Bild verglichen mit jener der Larven und Puppen. Tiefe Temperaturen hatten eine kurzere Imaginalzeit zur Folge. Die Schlupfwespen-Larven ernahrten sich von den Eiern der Schildlaus. Jede Larve verzehrte i. M. 83 % der abgelegten Eier des Wirtes. 2 Larven zusammen verzehrten 98,3 % der Eier. In letzterem Fall entwickelten sich die Larven zu 83,7 % zu ♂♂. Auch im Freiland dominierten, allerdings in geringerem Mase, die ♂♂: ihr Anteil betrug im November 58,3 %, im Dezember 52,0 %.

53- OZET Bu çalışma Aydın ili incir ağaçlarında zararlı Ceroplastes rusci (L.)'nin popülasyon değişimi ve bazı biyolojik özelliklerinin saptanması amacıyla 1999-2001 yıllan arasında yürütülmüştür. Örnekler İncirliova (Erbeyli köyü), Germencik, Buharkent ve Bozdoğan ilçelerinde belirlenen birer bahçede periyodik olarak mayıs ve eylül ayları arasında 15 günde bir, ekim ve nisan aylan arasında ise ayda birer kez olmak üzere çalışmalar sürdürülmüştür. Laboratuvara getirilen bulaşık dal ve yapraklar üzerindeki zararlılara ait tüm biyolojik dönemler canlı, ölü ve parazitli olarak sayılmıştır. Elde edilen sonuçlara göre, C. ruscfmn kışı, 2. ve 3. nimf dönemleri ile genç dişi ve ergin dişi dönemlerinde geçirdiği, yılda 2 döl verdiği bir dişinin ortalama 750 (450- 2023) adet yumurta bıraktığı saptanmıştır. Aynca, yapraklarda düşük yoğunlukta zararlının erkek bireylerine de rastlanmıştır. Kimyasal savaşın etkili olduğu biyolojik dönem olan 1. dönem nimfler birinci dölde en yoğun olarak haziran ayında, ikinci dölde ise ağustos ayında görülmüştür. Zararlının parazitli bireylerine en yoğun olarak yapraklar üzerinde, ergin dişi dönemindeki bireylerde, ağustos ayında ikinci dölde rastlanmıştır. -54- SUMMARY This study was carried out from 1999 to 2001 in Aydın province, and aimed to find out the population fluctation and some biological charecteristics of Ceroplastes rusci (L.) on fig trees. Samples were collected from İncirliova (Erbeyli village) Germencik, Buharkent and Bozdoğan districts. Periodically samplings were done between may and September each 15 day, and between October and april once a month. All biological stages, either alive or death and parashezed individual of pest were counted on the branches or leaves infected. According to the results obtained, it was determined that C.rusci overwintered as second, thirth nymph, young female and adult female stages on branches in Aydın province. They have two generations per year. It was determined that one female laids average 750 (450-2023) eggs. Also males of C. rusci were determined at low density on the leaves of fig trees. The mobile nymphes of C. rusci, which were the most susceptible stage to insecticide, were found in orchard at first generation in June and at second generation in August. Most of individuals infected with parazitoit of the pest were determined on the leaves at second generation, in August, at female stage individuals. 59

In the “uneven hatch” areas secondary parasitism has precluded Aphycus lounsburyi How. becoming, by itself, an adequate means of control of black scale, except, possibly, at irregular intervals. Eight hyperparasites are known to attack Aphycus and three others arc under suspicion. It is, however, of much value in the uneven-hatch areas as an aid to fumigation by evening up the hatch. In the interior or “even-hatch” areas, low temperatures which. cause retarded development of Aphycus, particularly in the pupal stage, during the one short period when it might alone control the scale, prevents its doing so. Aphycus, with Scutellista cyanea and Rhizobius ventralis, completes a sequence of enemies attacking the black scale and this fact offers a possibility of control. The distribution of Aphycus Lounsburyi has been so complete, both with and without human agency that it is safe to say there is hardly a citrus orchard, or for that matter a planting of ornamentals or growth of native shrubbery in Southern California, infested with black scale, in which it is not possible to find Aphycus or evidence of its work. In spite of the many factors operating to its disadvantage it is without question a most valuable addition to the parasite fauna of California.

Temperature influences the reproductive capacity of the Saissetia coffeae and its parasitoid. The lowering of temperatures increased the egg production of the scales. The high temperature (30°C) reduced the egg-laying of Metaphycus helvolus and resulted in a greater proportion of male progenies. However, oviposition and sex ratio of Scutellista cyanea were unaffected by high temperature. The high temperature too, accelerated the development of ovarian eggs of both parasitoids.