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The Australian cockroach (Periplaneta australasiae [Fabricius, 1775]) is a roach species that is scarcely found in Germany. On the territory of Saxony-Anhalt it has only been detected twice, these observations dating back more than 60 years. In early 2001, a mass appearance of the Australian cockroach was recorded in a greenhouse of the Magdeburg Zoological Gardens. The author is not aware of any other current appearance of the Australian cockroach in the land of Saxony-Anhalt.

Field experiments with the synthetic insecticides, Methomyl and Carbaryl, alone and in combination with the biological control agents, Bacillus thuringiensis (Bt) and Trichogramma evanescens, were conducted to control pests in yardlong beans, Vigna sesquipedalis, during the dry season 1998/1999. The experimental area was located at the Central Luzon State University in the province of Nueva Ecija on the Philippine main island Luzon. Carbaryl was applied against bean flies 5 days after plant emergence. Methomyl was sprayed against pod sucking insects and the bean podborer, Maruca vitrata, 45 days after plant emergence. The biological control agents were applied with the beginning of the flowering stage of V. sesquipedalis, when plants were first attacked by M. vitrata.

Major insect pests on V. sesquipedalis were cowpea aphid (Aphis craccivora), leafminer (Liriomyza sp.), and bean podborer (M. vitrata). Both, Bt and T. evanescens had no significant impact on yield. M. vitrata eggs, exposed for 48 hours in the fields to augmented T. evanescens, were used to measure field efficacy of the parasitoid. Highest parasitism rate was 13.3 %, thus, generally low.

Highest yield was obtained from plots treated with both synthetic insecticides. No significant difference in fresh pod yield was observed when, in addition to the synthetic insecticides, Bt and/or T. evanescens was applied. However, all treatments significantly out-yielded the untreated control.

The pathogenicity of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae against the tick fowl Argas persicargas persicus was studied. Bioassays revealed significant differences between the two fungi and the A. persicargas persicus stages exposed. The first nymphal instar was more highly susceptible to both fungi than the second nymphal instar. The unfed female of A. persicargas persicus was significantly less susceptible to both fungi than the engorged female. Application of M. anisopliae to sackcloth naturally infested with the tick fowl A. persicargas persicus induced mortality which reached 100 % three weeks after treatment under field conditions. The present study suggests that entomopathogenic fungi have good potential for tick fowl, A. persicargas persicus, control.

Various types of trap-tubs were tested both under controlled conditions in standardised trial series and in the field. New trap-tubs were poorly accepted by the animals, whereas weathered tubs were readily accepted within a very short period of time. The trapping mechanisms of tubs used in Lower Saxony and improved tubs in Hesse were both found to be suitable. The trapping method proved to be highly selective since long-tailed mice (Apodemus spp.) can easily escape by jumping onto the edge of the tub. Voles (Microtus agrestis, Clethrionomys glareolus) explored the inside of the tub and worked its exits with decreasing intensity during the time of captivity. They died of hypothermia within a few hours. Elimination of the trapped rodents by their natural enemies was not observed. The trials showed that trap-tubs are suitable for selective reduction of the density of field voles and red-backed voles in forests. The results also contribute to assessing the humaneness of the control method.

The parasitoids of Saperda populnea (L.) (Col.: Cerambycidae) were studied in Bulgaria during the period 1997 – 2001. Galls with pest larvae were collected from young aspen trees at eight locations (Sofia, Kokaliane, Plana, Churek, Gorni Lom, Gintzi, Dolno Kamartzi and Klisura) and examined under laboratory conditions. Four species were reared from 1118 galls containing overwintering pest larvae: Iphiaulax impostor (Scop.) (Hym.: Braconidae), Dolichomitus populneus (Ratz.), Schreineria populnea (Gir.) (Hym.: Ichneumonidae) and Billaea irrorata (Meig.) (Dipt.: Tachinidae). All of the parasitoids were solitary. Schreineria populnea was found as a new parasitoid of the host in Bulgaria. B. irrorata emerged mainly from late-stage S. populnea larvae; the remaining species from both early- and mid-stage larvae. In the parasitoid complex of S. populnea, the most numerous were B. irrorata (59.8 %) and D. populneus (29.4 %). The percentage of host larval parasitism varied from 2.4 to 33.3, with an average of 9.7 %. B. irrorata was the most important in reducing the pest number. The average mortality of S. populnea caused by the tachinid was 5.8 %, and the highest mortality observed in individual study was 20.2 %.

The character of a bark beetle outbreak, planning system, and implementation of IPM measures in a forest affected by intensive decline connected with honey fungus (Armillaria sp.) is described. It is possible to distinguish two levels of outbreak in the study area. The first level is characterized by spruce mortality connected with yellowing of spruce and presence of plant pathogens, mostly Armillaria sp. Forest stands have disperse infestations of bark beetles. Identification of infested trees and salvage cutting in time are problematic. In case of late processing of infested trees, the second level of outbreak could become manifest. The populations of bark beetle increase. Beetles could attack relatively healthy trees. The classical outbreak with forest edges and spot infestations starts. The identification of infested trees is easier. The application of pheromone trap barriers is effective. Thus, the second level of outbreak could be easily managed. The planning of IPM measures is concerned with localization of various pheromone trap systems in particular forest stands. It is based on field survey, data acquisition, estimation of swarming bark beetle population, and information of pheromone system effectiveness.

The distribution of microsporidian infections of browntail moth (Euproctis chrysorrhoea L.) populations in Bulgaria was studied. Of the 72 browntail moth populations in the regions of Balkan, Sredna Gora, Sakar Mountains, and Rodope Mountains, 21 were infected by Microsporidia. The Microsporidia belong to two genera –Nosema (Dihaplophasea, Nosematidae) and Endoreticulatus (Haplophasea, Encephalitozoonidae). Microsporidial infections caused by a Nosema were found in 14 populations, by an Endoreticulatus in 8 populations, and mixed infections of Nosema and Endoreticulatus were recorded from 3 populations. Endoreticulatus was present in Balkan, Sredna Gora, and the Sakar Mountains. Nosema infections were found in Sakar Mountains and Rodope, and mixed infections were recorded only from the Sakar Mountain populations.

Analytical studies concerning the species composition of galls occurring on the leaves of Quercus robur L. were conducted in 2000 in three localities: near an urban agglomeration of Kraków – the Wolski Forest, in a protected area – the Ojców National Park and in a managed forest – the Andrychów Forest District. In each of the selected localities 2000 leaves (a total of 6000 leaves) were randomly collected. A total of 2246 galls, including 1028 in the Andrychhów FD, were found. The galls represented 12 insect species. The species composition of galls in the Ojców NP (11 species) distinctly differed from those of the remaining two areas (7 species each). Neuroterus quercusbaccarum (L.) ♀♀ was the most abundant species in the managed forest. The index of occurrence frequency and the Agrell’s index of species co-existence have been calculated. The frequency of gall occurrence varied considerably in the investigated localities. On the basis of the Agrell’s index of species co-existence it was shown that the strongest bond existed between Neuroterus laeviusculus Schenck ♀♀ and Andricus ostrea (Hartig) ♀♀ in the managed forest.

The present paper deals with the efficiency of the mixed biocide GCSC-BtA against vegetable pests of five orders of arthropod insects in the south-eastern China, i. e., diamondback moth, Plutella xylostella (L.); green peach aphid, Myzus persicae (Sulzer); yellow-fanded flea beetle, Phyllotreta vittata Fabricius; vegetable leaf miner, Phytomyza nigricornis Macquart; and vegetable spider mite, Tetranychus neocaledonicus Andre. The results show that the mixed biocide GCSC-BtA has a higher efficacy of control against all of the five pests than the commercial biocide B.t. and insecticide Diazinon. GCSC-BtA gave a higher mortality value of 92.18 % against P. xylostella as compared to the biocide B.t. with a value of 64.70 % and Diazinon with a value of 50.00 %. Similar mortalities were obtained with the other four pests regarding the efficacy of the three products tested against them.

The concentration-mortality regression equations were calculated by the probit analysis, from which the average mortalities were calculated. The values calculated for GCSC-BtA were 81.13 % for P. xylostella, 75 % for M. persicae and T. neocaledonicus, 69.23 % for P. vittata, and 61.03 % for P. nigricornis as compared to those caused by Diazinon: 33.33 %, 27.42 %, 66.31 %, 44.54 %, 19.65 % for P. xylostella, M. persicae, P. vittata, P. nigricornis, and T. neocaledonicus, respectively. Based on LC₅₀, P. xylostella was most susceptible to GCSC-BtA with a LC₅₀ value of 0.3445, followed by B.t. with a value of 0.8404 and Diazinon with a value of 1.3160. The LC₅₀ value of GCSC-BtA for M. persicae was 0.4660 which was about three times less than that of Diazinon. LC₅₀ value of GCSC-BtA for P. vittata was 0.3954 which was about the same as that of Diazinon. P. nigricornis and T. neocaledonicus were also much more susceptible to GCSC-BtA than to B.t. and Diazinon. It is concluded that GCSC-BtA kills more target pests than B.t. and is more effective than Diazinon in controlling the vegetable pests.

This paper deals with the influence of the mixed biocide GCSC-BtA on the pupal and adult stages of Apanteles plutellae Kurd. (Hym., Braconidae) and its host, Plutella xylostella (L.) (Lep., Plutellidae). The results show that mortalities of the pupae of P. xylostella in the direct-dip bioassay were 84.67 %, that of the adults in the residue bioassay at 1.2500 mg/ml concentration of GCSC-BtA were 78.00 % which were significantly higher than the mortality values for the pupae with 54.62 % and adults with 48.13 % of A. plutellae. In contrast, cypermethrin showed extremely high toxicity to the pupae with 94.58 % and adults with 86.00 % mortality values of A. plutellae as compared to the low mortality values of 42.14 % for the pupae and 32.11 % for the adults of P. xylostella, with the same concentrations and bioassay methods. The LC₅₀ values of GCSC-BtA were 0.3402, 0.5516 and 1.2405, 1.9480 mg/ml for the pupae and adults of P. xylostella and A. plutellae, respectively, while the LC₅₀ values for cypermethrin were 1.5652, 2.3471 and 0.1096, 0.1152 mg/ml, respectively. GCSC-BtA was found more toxic to the pupae and adults of P. xylostella and safer to the pupae and adults of A. plutellae than cypermethrin. The possibilty of using GCSC-BtA against P. xylostella under partial control by A. plutellae in vegetable fields is discussed.