Anzeiger für Sch?dlingskunde最新文献

The side effects of the neonicotinyl compound thiamethoxam on the brood of bumble bees (Bombus terrestris L.) were investigated on tomatoes in plastic tunnels and glasshouses.

Preceeding trials had revealed a strong contact and stomach activity of the compound by foliar application. A decisive improvement was obtained by replacing the foliar by drip irrigation of thiamethoxam at rates between 150 and 161 g ai/ha. The mortality figures of all bumble bee stages dropped to the level in the untreated control. No dead bumble bees were found in the thiamethoxam treated tunnels/glasshouses on the ground.

Thiamethoxam could be rated as being harmless to bumble bees with a single application through the irrigation system. No spilling of this compound during the application should occur to avoid intoxication of adult bumble bees by oral uptake or contact contamination during the cleaning process. If multiple applications via the irrigation system or under any hydroponic growing conditions is considered, further sequential testing of this mode of use is recommended.

Canningia tomici sp. n. (Microsporidia, Unikaryonidae) infects the midgut epithelium, the gut muscules, Malpighian tubules, connective tissues, adipose tissues and the gonads of the pine shoot beetle, Tomicus piniperda (L.) (Coleoptera, Scolytidae). The infection is present in populations of Tomicus piniperda in Europe and in the United States. Uninucleate oval single spores occur in two sizes: 2.8 ± 0.4 × 1.4 ± 0.4 μm and 3.8 ± 0.3 × 2.0 ± 0.2 μm. The polar filament of this microsporidium is fixed subapically in a flat anchoring disc. The thick posterior lamellae of the binary polaroplast are asymmetric due to the lateral fixation of the polar filament.

The predatory mite Typhlodromus pyri Scheuten (Acari, Phytoseiidae) has been reported as an important predator of the European red mite, Panonychus ulmi (Koch) (Acari, Tetranychidae) in apple culture and vineyards at below 25 °C. However, sufficient biological data was lacking on its efficiency at temperatures above 25 °C. Therefore, the purpose of the present laboratory work was to obtain experimental data on prey consumption during development as well as longevity and reproduction of T. pyri on apple leaf discs and in Plexiglas cells at constant temperatures of 25 ± 2 °C and 30 ± 2 °C with P. ulmi as prey.

The results showed that mean daily and total prey consumption by both the nymphs and adults of T. pyri decreased significantly on both the arenas as the temperature was increased from 25 °C to 30 °C, whereby adult prey consumption, both mean daily and total, was higher than that of nymphs. Prey consumption by both the nymphs and adults was significantly higher in the Plexiglas cells than on the leaf discs at both temperatures. Mean total prey consumption during nymphal development was 16.1 (♀♀) and 12.8 (♂♂) at 25 °C compared to 7.0 (♀♀) and 5.8 (♂♂) preys at 30 °C on the apple leaf discs and 46.0 (♀♀) and 38.5 (♂♂) at 25 °C compared to 25.2 (♀♀) and 20.3 (♂♂) preys at 30 °C in the Plexiglas cells. Mean duration of nymphal development was similar for the two sexes at the same temperature, but it was longer at 25 °C than at 30 °C. It was 6.0 and 4.0 days on the apple leaf discs while 7.0 and 6.0 days in the Plexiglas cells at 25 °C and 30 °C, respectively. Mean daily and total prey consumption by both male and female adults also decreased with the increasing temperature, whereby the females consumed more than double the mean total number of prey than the males on both the arenas of observation and at both temperatures: 355.4 versus 149.7 preys at 25 °C and 192.2 versus 85.6 preys at 30 °C on the leaf discs and 826.8 versus 374.5 preys at 25 °C and 488.9 versus 187.9 preys at 30 °C in the Plexiglas cells. Longevity of the females was longer than males on both arenas and at both temperatures and it was longer at 25 °C than at 30 °C. Mean total longevity on the apple leaf discs was 68.3 (♀♀) and 50.8 (♂♂) days at 25 °C compared to 52.5 (♀♀) and 36.8 (♂♂) days at 30 °C, while in the Plexiglas cells it was 91.0 (♀♀) and 65.8 (♂♂) days at 25 °C compared to 75.3 (♀♀) and 48.5 (♂♂) days at 30 °C. Reproduction in females also decreased significantly with increasing temperature. It decreased from 62.0 to 39.0 eggs/female on the leaf discs and 75.0 to 47.1 eggs/female in the Plexiglas cells. The females laid significantly higher numbers of eggs at both temperatures in the Plexiglas cells than on the leaf discs. Oviposition period in females was 30 days at 25 °C on both the arenas, while at 30 °C it was 26 days on the apple leaf discs and 27 days in the Plexiglas cells.

This paper presents the results of a research project concerning bark beetle populations in Norway spruce stands managed under a nature protection regime in national parks in Tatra Mountains in Poland and Slovakia. The preliminary data on bark beetle occurrence and related selected stand characteristics are presented. The dynamics of a bark beetle outbreak that occurred from 1994–97 in the stands localized on both sides of the state border and in various nature protection regimes is analyzed retrospectively. The data concerning the tree/stand characteristics, i.e. DBH and increment of trees are discussed in relation to its potential role in the mechanism for the spread of bark beetle populations. The patterns of the spatial distribution of trees attacked during the research period (1999–2001) are described.

An aphid and virus survey was conducted from 1993 and 1999 on the eastern lowlands in Hungary. Aphid flight was monitored with two yellow pan traps placed on the edge and in the middle of seed potato fields. From 1993 and 1997, aphid flight was monitored with a Rothamsted type suction trap. The aphid and virus survey was continued in four different regions of Hungary in 2000. Aphid flight activity recorded by the suction trap and the yellow pan traps was different. Cumulative vector intensity based on yellow pan trap catches revealed a greater variation between years than among the different locations. In 4 years out of 8, aphid flight was less intensive and quality seed potato was harvested regardless of the production site. Cumulative vector intensity is a good means to forecast the time of haulm destruction in seed potatoes.

The effect of apple cultivar on the distribution of Amblyseius andersoni was studied in an experimental orchard where tetranychids were virtually absent and eriophyids reached low to moderate populations. Seven apple scab-resistant cultivars, showing some differences in their leaf morphology, were compared. Each cultivar was grafted onto three different rootstocks inducing increasing vigor. The intraplant distribution of A. andersoni was also studied by monitoring predator densities on basal and apical leaves. In the first year, the colonization of different cultivars by A. andersoni showed definite patterns, sometimes associated with the abundance of the eriophyid Aculus schlechtendali. In the second experimental season, eriophyids reached negligible levels and the effect of cultivar on A. andersoni abundance was less clear. Florina and N.Y. 18 491 cultivars were colonized in both years by relatively high phytoseiid numbers, while TSR 29T219 and Priscilla showed low populations in at least one season. The results observed on the remaining cultivars were intermediate or indefinite. The role of leaf pubescence on phytoseiid colonization is discussed.

Conjugation of δ-endotoxin from Bacillus thuringiensis with abamectin, a toxin of Streptomyces avermitilis, was carried out to form a new type of biocide, GCSC-BtA based on “Germany-China Scientific Cooperation” research, for the control of agricultural insect pests. The strategy for biochemical linkage was designed by conjugating an amino group in B.t. protoxin with a carboxyl group in carboxylated abamectin under the treatment of conjugator EDC [1-Ethyl-3-(3-dimethylaminopropyl carbodiimide Hydrochloride)]. The formation of B.t. protoxin was processed by solubilizing B.t. crystal in 25 mM dithiothreitol (DTT) at 37 °C for 2 h. The carboxylated abamectin was formed by carboxylating the NaH-activated abamectin with 10 mg/ml butyric anhydride at 111 °C in a water-circumfluent condensation device for 2 h. The conjugating reaction, consisting of 5 mg/ml B.t. protoxin, 10 mg/ml carboxylated abamectin and 19.17 mg/ml EDC, was successfully conducted at room temperature for 24 h. Significant differences were found between pure abamectin, carboxylated abamectin and the conjugated BtA by means of UV-photo absorptions recorded at wavelengths 354, 438, 518, 600 nm (P < 0.01). LT₅₀ of the conjugated GCSC-BtA to the 3^rd instar larvae of Plutella xylostella (L.) (Lep., Plutellidae) was 35.27 μg a.i./ml, about 62 % and 76 % of that caused by the B.t. protoxin and the caxboxylated abamectin, respectively. The conjugated GCSC-BtA caused 87.14 % mortalities in larvae of P. xylostella, 93.75 % in adult Myzus persicae (Sulzer) (Hom., Aphididae) and 89.33 % in adult Phyllotreta vittata Fabricius (Col., Chrysomelidae) as compared to 48.33 % by the B.t. crystal only in P. xylostella. The symptoms caused by conjugated GCSC-BtA in the 3^rd instar of P. xylostella were black color in the head part and white-yellow in the abdomen of dead larvae, which differed from the black color or the white-yellow all along the body caused by either the B.t. crystal or the abamectin, respectively. It was concluded that the conjugated GCSC-BtA biocide had a broader host spectrum and a faster killing speed than either the B.t. crystal or abamectin alone for the control of agricultural pests.

The Aphidoidea (Homoptera) has 29 species which attack coniferous trees in Turkey. The family Aphididae has 25 (Aphidinae, 1; Lachninae, 22; Mindarinae, 2) species and the Adelgidae, 4. The tribe Cinarini in Lachninae has alone 22 species most of which are important. Especially Cinara cedri Mimeur on Cedrus libani and C. pilicornis (Hartig) on Picea spp. are harmful species. Schizolachnus pineti (Fabricius) is also very important. An Eastern Palearctic species in the tribe Macrosiphini in Aphidinae, Elatobium momii (Shinji), is numerous on Abies bornmülleriana in Bursa-Uludağ forests. Pineus orientalis (Dreyfus) in the family of Adelgidae (Chermesidae) is the most destructive in our Picea orientalis forests in Artvin area (Eastern Black-Sea Section). 21 species out of 29 aphids on coniferous trees are of European origin; only 4 are Mediterranean, 2 Caucasus and Turkistan, one Eastern Palearctic and one of Cosmopolitan origin.

Distribution of the cherry bark tortrix, Enarmonia formosana (Scopoli) (=CBT) was determined by detecting the presence of their frass tubes on the trunk of rosaceous shrubs and trees throughout the Czech Republic. Tree disjunctive areas of CBT were indicated in the country. The overall distribution of CBT approximates the annual isothermes 8–9 °C and 10–11 °C, but a number of zonal exceptions were also determined. The occurrence of CBT on sweet cherry, Prunus avium (L.) was the key target association, but P. armeniaca L., P. cerasus L., P. divaricata Ledeb., P. domestica L., P. persica L., and P. serrulata Lindley were also identified on the distributional map.

Ancient Egyptian insect relics were accidentally enclosed in embalming resin which leaked from a priest's mummy and solidified on the floor of a wooden coffin from the end of the XVIII^th Dynasty (presumably 1323 – 1295 BC). The preserved insect relics were blowflies (Calliphoridae) recognized as Chrysomya marginalis or Chrysomya megacephala whose larvae had developed by feeding on the deceased's body prior to mummification as well as furniture beetles (Anobiidae) being either Oligomerus ptilinoides or Priobium carpini whose larvae had ingested the coniferous wood of the coffin. It is most likely that the human corpse and coffin were first attacked by the blowflies and furniture beetles prior to embalming, while infestation of the insect remains and textiles by Anthrenus sp. (Dermestidae) occurred in our time.