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Cool and wet weather in some periods of the season generally supressed the RWA (Diuraphis noxia Kurdj.) populations in the Czech republic in 2001. However, some sites manifested population levels ranging out of the population mean stated per area, and these sites were also apparently responsible for respective peaks of alate aphids sampled by suction traps. An analysis of these sites determined them to be attributed to some poor quality barley fields in a warmer area of the state. RWA is known to vary in all-over populations in different years, and the year 2001 illustrated its capability of its surviving even unfavourable periods and seasons, remaining well-established in the area.

Percentage survival in aqueous suspensions and infectivity of six Egyptian entomopathogenic nematode isolates from the genus Heterorhabditis varied during the hot period of the year with daily temperature range from 18 to 24 °C. The isolate designated as AS1 had the highest mean of survival (87 %) and infectivity to Galleria mellonella larvae (90 %) after 10 days. When the nematodes coexisted with cytoplasmic polyhedrosis virus of 100 × 10⁶ polyhedra inclusion bodies/ml, which was reproduced within and killed Rhynchophorus ferrugineus larvae, the nematode survival was adversely and progressively affected by the increase in the viral suspension. Among tested concentrations, a viral suspension equal to one-fifth size of the nematode and virus suspension is the best for nematode activity in integrated control against the red palm weevil.

Different concentrations of Neem Azal-T/S, an insect growth regulator (IGR) (antiecdysone) and various other insecticides were tested against the pistachio psyllid (Agonoscena targionii) affecting pistachio (Pistacia vera L.), in northern Syria. From 1997 – 99, three applications were made annually, in April, May, June or July. Results revealed that Neem Azal-T/S, at the rate of 0.5 and 0.7 %, Flufenoxuron, Teflubenzuron, and the antagonistic fungus Beauveria bassiana Bals. were highly effective against the psyllid especially on the 1^st and 2^nd nymph instars in the April application. The possibilities of using these pesticides in integrated management against pistachio psyllid in Syria are discussed.

The parasitoid complex of Paraphytomyza populi (Kltb.) (Diptera: Agromyzidae) was studied in Sofia, Bulgaria in 1997. Poplar leaves with P. populi larvae and pupae were collected from poplar stump shoots and examined in a laboratory. As a result, eleven parasitoid species were established: Chorebus albipes (Haliday) (Hymenoptera, Braconidae), Pediobius metallicus (Nees), Danuviella subplana Erdos, Chrysocharis nephereus (Walker), Chrysocharis pubicornis (Zetterstedt), Diglyphus crassinervis Erdos, Diglyphus isaea (Walker), Diglyphus albiscapus Erdos, Cirrospilus diallus Walker, Cirrospilus pictus (Nees) (Hymenoptera, Eulophidae) and Elasmus sp. (Hymenoptera, Elasmidae). Six species (D. crassinervis, D. isaea, D. albiscapus, C. diallus, C. pictus and Elasmus sp.) have been recorded as new parasitoids of P. populi. The genus Danuviella was found for the first time in Bulgaria. Five species (C. albipes, P. metallicus, D. subplana, D. crassinervis and D. albiscapus) are new records for the fauna of the country. The total mortality of P. populi caused by parasitoids was 19.1 % and 49.0 % for the overwintering and the summer generations, respectively. P. metallicus was the most important in reducing the pest number.

A 4-year (1996 – 99) survey of the biology of L. serricorne (F) (Coleoptera, Anobiidae) on stored tobacco has taken place in Thessaloniki, northern Greece. For the trapping of the adults, pheromone (‘New Serrico’ and ‘Black Stripe Moth’) as well as electric (black light) traps were used. The first generation adults emerging from larvae hibernating inside the tobacco bales appeared flying on the 17/5, 16/5, 28/4, and 30/4 of the years 1996, 1997, 1998, and 1999, respectively. In parallel observations, adults inside the bales were found on the 14/5, 12/5, 23/4, and 26/4 of the above-mentioned years, respectively. Termination of flights, in all the years concerned, took place during October or November, while the last flights of November were recorded in temperatures of about 13 °C.

A study concerning the winter mortality of a sub-corticolous population of Ips typographus and its parasitoids has been carried out in the south-eastern Alps (Italy) during the winter 1997/98. Three attacked spruce trees were sampled three times (November, February and April) by collecting infested bark disks (1 dm² each). All insects that emerged from the bark or died in the samples before emergence were counted. The mean number of living Ips typographus occurring under the bark decreases by 49 % from November to April. Winter mortality mainly affects larval stages and young adults. The same trend was observed for the parasitoids Coeloides bostrychorum (48.5 %) and Roptrocerus xylophagorum (47.5 %).

Pymetrozine is the first and only substance from the group of azomethine pyridines, a novel class of insecticides. The spectrum of activity covers sucking pests such as aphids, whiteflies and planthoppers.Tests were carried out in the laboratory and under field conditions to evaluate its impact on beneficial arthropods.In laboratory tests it demonstrated full selectivity against predaceous Coleoptera, Heteroptera, Neuroptera and the predatory mite Typhlodromus pyri.Following a single application at 250/200 g a.i./ha on cotton in Egypt and in the USA, the regular sampling of predators over a period of three weeks revealed a similar population development in the pymetrozine and the untreated control plots. On okra, a vegetable crop in Egypt, it suppressed populations of Aphis gossypii with two sprays at 100 g a.i./ha for the whole observation period of 23 days. It also allowed the survival of predators.These positive features make pymetrozine an ideal component in situations where sucking pests have to be controlled and natural enemies can play a substantial role as complementary control tools.

The present paper deals with laboratory studies on side-effects of the mixed biocide GCSC-BtA on Plutella xylostella (L.) (Lep., Plutellidae) and its predators, e. g. Amblyseius longispinosus (Evans) (Acari, Phytoseiidae), Erigonidium graminicola (Sundvall) (Araneae, Linyphiidae), Orius similis Zheng (Het., Anthocoridae) and Coccinella septempunctata L.(Col., Coccinellidae), in comparison to the commercial insecticides, e. g. Abamectin, Tebufenozide, Dichlorvos, Cartap and Lambda-cyhalothrin.The results showed that GCSC-BtA was highly toxic to the 3^rd instar of P. xylostella with 91.18 % mortality, followed by Cartap with 84.38 %, Abamectin with 78.00 %, Tebufenozide with 75.57 %, Lambda-cyhalothrin with 63.75 % and Dichlorvos with 50.86 % mortality. On the other hand, GCSC-BtA was found to be comparatively less toxic to the predators, causing 31.11 %, 13.33 %, 11.54 % and 6.00 % mortalities in A. longispinosus, E. graminicola, O. similis and C. septempunctata, respectively. For comparison, the mortalities recorded for Abamectin, Tebufenozide, Dichlorvos, Cartap, Lambda-cyhalothrin were 72.94 %, 55.55 %, 70.00 %, 53.26 % and 98.85 % in A. longispinosus, 46.51 %, 55.10 %, 60.00 %, 46.00 % and 73.68 % in E. graminicola, 22.00 %, 16.00 %, 35.71 %, 26.78 % and 81.03 % in O. similis, 15.55 %, 19.64 %, 28.00 %, 16.66 % and 41.79 % in C. septempunctata, respectively.Cluster analysis was introduced to group the mortalities caused by the treatments into three toxicity groups with the distance of D = 4.1. The 1^st group consisted of GCSC-BtA characterized with low toxicity to all the predators tested with 15.49 % mortality on average (highest 31.11 % and lowest 6.00 %). The 2^nd group consisted of Abamectin, Tebufenozide, Dichlorvos and Cartap with moderate toxicity to the predators with 39.96 % mortality on average. The 3^rd group included Lambda-cyhalothrin with high toxicity to the predators with 73.83 % mortality on average (highest 98.85 % and lowest 41.70 %). The susceptibility of the pest and its predators to GCSC-BtA and the insecticides is discussed. GCSC-BtA as a biological control agent is recommended for use in the integrated pests control programs in the vegetable fields.

The present paper deals with the effect of the biocide GCSC-BtA on population dynamics of cabbage pests, i. e., Plutella xylostella (L.) (Lep., Plutellidae), Brevicoryne brassicae (L.) (Hom., Aphididae), Liriomyza sativae Blanch. (Dip., Agromyzidae), Phyllotreta vittata Fabric. (Col., Chrysomelidae) and their natural enemies, i. e., Apanteles plutellae Kurdj. (Hym., Braconidae), Erigonidium graminicola (Sundv.) (Araneida, Linyphiidae), Coccinella septempunctata L. (Col., Coccinellidae), in common head cabbage (Brassica oleracea var. capitata) fields in the southeastern China. The experiments were conducted at the experimental farm of Fujian Academy of Agricultural Sciences, Fuzhou, PR China in April – June, 2001.The results showed that, at the end of sampling, the pest populations of P. xylostella, B. brassicae and P. vittata reached averages of 39.7, 68.3 and 6.2 ind. / 30 plants in the plot treated with GCSC-BtA, which were about 1.5, 11 and 0.7 times lower than those treated with methomyl, respectively. In contrast, the natural enemy populations were, on average, 23.5 ind./30 plants for A. plutellae, 24.6 ind./30 plants for E. graminicol and 12.2 ind./30 plants for C. septempunctata in the plot treated with GCSC-BtA, about 6, 5 and 3 times higher than for those treated with methomyl, respectively. The GCSC-BtA biocide demonstrated greater effectiveness in controlling the cabbage pests, e. g., P. xylostella, B. brassicae and P. vittata, having final decreasing ratios of 83.60, 97.05 and 53.67 % compared to 57.63, 64.89 and 30.88 % with the methomyl insecticide. However, it was less toxic to natural enemies, e. g., A. plutellae, E. graminicola and C. septempunctata, final decreasing ratios being 47.68, 17.84, 27.81 %, than methomyl, with 90.94, 80.80, 74.55 %, in comparison to the populations in the control plots, respectively. So, because of the low toxicity of GCSC-BtA to the natural enemies, it is recommended that, on one hand, its application should be carried out after mass migration of the pests to the fields, on the other hand, the alternative agent GCSC-BtA should be used with the aim of minimizing the harmfulness to the natural enemies in the whole program of integrated pest management in cabbage fields.

Susceptibility of immature individuals of the spider Theridion impressum to 17 pesticides (6 insecticides, 4 acaricides, 4 fungicides and 3 herbicides) was tested in the laboratory. The pesticides were applied at recommended rates in a Potter tower. Mortality was evaluated for 4 subsequent days. Broad-spectrum insecticides, cypermethrin+chlorpyrofos (Nurelle), α-cypermethrin (Vaztak), and deltamethrin (Decis), were toxic to spiders. Selective insecticides, pirimicarb (Pirimor), Bacillus thuringiensis (Novodor), and triazamate (Aztec), were harmless. All tested acaricides, pirimiphos-methyl (Actellic), flufenoxuron (Cascade), τ-fluvalinate+thiometon (Mavrik), and bifenthrin (Talstar) showed high toxicity. Of the fungicides, dithianon (Delan), benomyl (Fundazol), iprodione (Rovral), and dodine (Syllit), only dithianon was slightly harmful, while the remaining fungicides were harmful. All herbicides, metazachlor (Butisan), clomazone (Command), and clopyralid (Lontrel), were harmless to T. impressum. Three selective insecticides, 3 fungicides and 3 herbicides are recommended for use in plant protection.