The two antimoulting compounds diflubenzuron and zertel showed an adverse effect on the egg parasitoid Trichogramma evanescens and the aphid lion Chrysoperla carnea. Parasitism by T. evanescens was markedly decreased and the immature stages failed to complete their development. When parasitism took place before spraying the insecticides, emergence of adults, longevity and fecundity markedly decreased. Both insecticides showed adverse effects on the duration and pupation of treated eggs or larvae of Chrysoperla. Adults of C. carnea poisoned with any of the 2 insecticides laid markedly less eggs than normal adults. Zusammenfassung Biologische Aspekte zur Bewertung von Zertel und Diflubenzuron in ihrer Wirkung auf Trichogramma evanescens Westw. und Chrysoperla carnea Steph. Die beiden Häutungshemmer, Zertel und Diflubenzuron, hatten auf den Eiparasiten Trichogramma evanescens und den Blattlauslöwen Chrysoperla carnea eine ungünstige Wirkung. Die Parasitierungsrate von T. evanescens verringerte sich deutlich und die Larvenstadien konnten ihre Entwicklung nicht beenden. Bei der Applikation der Häutungshemmer nach der Parasitierung des Wirts wurden das Schlüpfprozent, die Lebensdauer und die Fekundität von T. evanescens negativ beeinflußt. Auf C. carnea‐Eier und ‐Larven wirkten beide Häutungshemmer ungünstig auf die Länge beider Entwicklungsphasen sowie auf die Verpuppung. C. carnea‐lmagines, die mit behandelter Beute gefüttert wurden, legten signifikant weniger Eier ab als unbehandelte Weibchen.

Background: For the sake of environmental safety, many sulfur formulations were recommended in many Integrated Pest Management (IPM) programs to protect, particularly, edible vegetables and fruit trees from insect and mite pests as well as plant pathogenic diseases. Such formulations, at the recommended application rates, proved to be safer to mammals. Regarding their safety to beneficial arthropods, diversified results were reported. This study was designed to investigate and evaluate the impact of sulfur formulation against some natural enemies naturally prevailing in some vegetable crops. Method: Sulfur formulation (Agricultural Sorell-98%) was recommended by the Ministry of Agriculture, Egypt, as a protectant for vegetable crops against some plant diseases and piercing-sucking pests (aphis, whiteflies, thrips, and mites) at the rate of 30 kg/Feddan 30 days post plantation. The experiment was undertaken in two similar rectangle areas during the season (2016/2017). Each area about 700 m 2 was sown with marrow plant. The first area was divided longwise into two halves, each half comprises six rows and divided horizontally into four plots each about 75 m 2. Similar plots were done in the second area but no treatments were made (check area). Monitoring the density fluctuations of the natural enemies in the target areas was undertaken at certain intervals (just before dusting, 2, 12, 24, 48, and 72 h and 7 days after application) and achieved early in the morning (7 am). Fifty plants were inspected per plot per time interval in treated and untreated areas. The average number of each natural enemy/time interval and percent increase or decrease in the population density in the treated half and the untreated one were calculated. Results: The obtained data revealed that the least number of the prevailing adults was recorded at the treated plot after 2 h post treatment for Coccinella and after 12 h for Stethorus adults. In addition, it could be observed that the mean number of the recorded adults occurred in the untreated plot of the first area was increased significantly than that of the untreated second area at 12 and 48 h and after 1 week post treatment, this could be referred to the following: when the treated plot was sprayed with sulfur compound, most of the prevailing adults escaped from the dust and migrate to the untreated plot or other clean plants (untreated plot or other surrounding plants), then they returned back gradually to the treated plot. Conclusion: The obtained results clarify that the intelligent handling of sulfur formulations in order to control some pests and plant diseases with minimal or harmless effects towards the adult predators under investigation must be taken in consideration; thus, this could be more favorable to keep the environment clean and non-polluted. In addition, results throw light on that Stethorus punctillum was more susceptible than Coccinella undecimpunctata especially for the sulfur residues on treated plants.

The larvae of the aphid lion Chrysoperla carnea (Steph.) were reared on a semi-arti®cial diet for laboratory rearing. Algae, Chlorella vulgaris Beij was used as a source of protein for the nutrition of the predator. Feeding the newly hatched larvae of the predator on water extract of the algae by using a small piece of sponge, extended the larval duration up to 30 days, and the larvae failed to pupate. The addition of carbohydrates, salts and vitamins was necessary to the larvae to complete their development to reach the pupal and adult stages. Normal adult longevity and egg deposition were obtained after the addition of the carbohydrates, salts and vitamins.

Temperature had various effects on the predacious efficacy of immature and mature stages of the coccinellid predator, Stethorus punctillum on the two-spotted spider mite, Tetranychus urticae. In the case of immature stages, food consumption at the lowest tested temperature (158C) was significantly higher than that at higher temperatures (25 and 358C). On the contrary, positive correlation between food consumption and temperature was evaluated in the case of adult predator. Regarding predator responses to different prey density, a high positive correlation between food consumption and prey density was evaluated among 4 th instar larvae of the predator, followed by adult predator, while younger instars did not show reasonable increases with increasing prey densities. These results confirm that larval and adult stages of S. punctillum exhibit ''Type II'' functional response. In conclusion, the 4 th instar larvae and adult predator are the most preferable stages in winter and summer crops to control T. urticae, respectively.

Background: The larval internal parasitoids in the genus Meteorus attack certain lepidopterous larvae in different Egyptian fields. Two species, M. rubens and M. gyrator were the most abundant species reared from several lepidopterous larval species, which feed on different host plants in the two selected Governorates in Egypt throughout two successive years. Aim: This work presents a method specifically designed to improve the abundance and the parasitizing potential of M. gyrator in open fields to parasitize and develop on a broad range of noctuid’s pests by releasing considerable number of the parasitoid adults. Also it deals with some aspects of the basic biology of M. gyrator parasitizing Spodoptera littoralis and Autugrapha ni, as mass-rearing hosts. Methodology: 1- Population Dynamics Biweekly samples of lepidopterous larvae were collected from different host plants in the fields of Giza and Faiyum Governorates, for two successive years (November, 2017 to October, 2019). Collected larvae were confined individually under constant conditions until pupation or the emergence of the internal parasitoid’s larvae for pupation. 2- Laboratory Rearing Cultures of some insect larvae, Heliothis armigera, Spodoptera exigua, Agrotis ipsilon, Sesamia cretica, S. littoralis and Autographa ni were reared in laboratory under constant conditions to act as hosts for mass-production of the parasitoid, M. gyrator. Results: Obtained results reveal that A. ipsilon was the main host of M. rubens, it was more abundant in both years and localities of the survey. Meteorus gyrator was recorded at fewer numbers; it was reared from S. littoralis, S. exigua, S. critica, Heliothis spp. and Autographa spp. The parasitism percentage by M. rubens averaged 23.10% at Giza. While in the case of M. gyrator it averaged 3.25%. In Faiyum, the corresponding figure averaged 12.96% parasitism for M. rubens; while it averaged 6.93%, for M. gyrator. To increase the efficacy of M. gyrator, mass production experiments were carried out, suggesting that Autographa ni was the most suitable for mass-rearing than S. littoralis. Conclusion: To increase the efficacy of M. gyrator as an endoparasitoid, its numbers in the field should be increased by releasing a considerable number of adults, to control lepidopterous larval pests.

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