Verified and potential pathogens of predatory mites (Acari: Phytoseiidae)

Several species of phytoseiid mites (Acari: Phytoseiidae), including species of the genera Amblyseius, Galendromus, Metaseiulus, Neoseiulus, Phytoseiulus and Typhlodromus, are currently reared for biological control of various crop pests and/or as model organisms for the study of predator¿prey interactions. Pathogen-free phytoseiid mites are important to obtain high efficacy in biological pest control and to get reliable data in mite research, as pathogens may affect the performance of their host or alter their reproduction and behaviour. Potential and verified pathogens have been reported for phytoseiid mites during the past 25 years. The present review provides an overview, including potential pathogens with unknown host effects (17 reports), endosymbiotic Wolbachia (seven reports), other bacteria (including Cardinium and Spiroplasma) (four reports), cases of unidentified diseases (three reports) and cases of verified pathogens (six reports). From the latter group four reports refer to Microsporidia, one to a fungus and one to a bacterium. Only five entities have been studied in detail, including Wolbachia infecting seven predatory mite species, other endosymbiotic bacteria infecting Metaseiulus (Galendromus, Typhlodromus) occidentalis (Nesbitt), the bacterium Acaricomes phytoseiuli infecting Phytoseiulus persimilis Athias-Henriot, the microsporidium Microsporidium phytoseiuli infecting P. persimilis and the microsporidium Oligosproridium occidentalis infecting M. occidentalis. In four cases (Wolbachia, A. phytoseiuli, M. phytoseiuli and O. occidentalis) an infection may be connected with fitness costs of the host. Moreover, infection is not always readily visible as no obvious gross symptoms are present. Monitoring of these entities on a routine and continuous basis should therefore get more attention, especially in commercial mass-production. Special attention should be paid to field-collected mites before introduction into the laboratory or mass rearing, and to mites that are exchanged among rearing facilities. However, at present general pathogen monitoring is not yet practical as effects of many entities are unknown. More research effort is needed concerning verified and potential pathogens of commercially reared arthropods and those used as model organisms in research

Use of the DD 136 strain of Neoaplectana carpocapsae Weiser (Rhabditida: steinernematidae) for control of corn earworm (Lepidoptera: noctuidae)

Field trials were conducted in the summer of 1981 to determine the effectiveness of the DD 136 strain of Neoaplectana carpocapsae Weiser in controlling, corn earworm, Heliothis zea(Boddie) larvae. The corn ears were artificially infested with H. zea larvae and subsequently sprayed with nematodes at 0, 4 × 103 and 4 × 104 nematodes/ml suspension. Eighty-eight percent control was obtained with 4 × 104 nematodes/ml in early June but less, 80% and 58% respectively, was observed in late June and early July. Thus, N. carpocapsae, survives better and is more effective in the early part of the season. All ears in the treated and control plots received some damage, but damage in all the treated plots was significantly lower than in the control

Perturbative correlation functions of null Wilson loops and local operators

We consider the correlation function of a null Wilson loop with four edges and a local operator in planar MSYM. By applying the insertion procedure, developed for correlation functions of local operators, we give an integral representation for the result at one and two loops. We compute explicitly the one loop result and show that the two loop result is finite

Zmiany patomorfologiczne w jelicie cienkim i wątrobie bobra europejskiego (Castor fiber L. 1758): studium przypadku

Pathomorphological Changesin the Small Intestine and Liver of the European Beaver (Castor fiber L. 1758): a case study.The aim of thestudy was to examine and describe the morphology and patomorphology of small intestine and liver of European beaver (Castor fiber). In natural environment beavers are in constant contact with various both internal and external parasites. Histological analysis revealed the pathological changes within the digestive track and liver indicating long-term inflammation. It was hypothesized that the observed inflammation was caused by the parasites not related to beavers so far.Zmiany patomorfologiczne w jelicie cienkim i wątrobie bobra europejskiego (Castor fiber): studium przypadku. Celem pracy była ocena patomorfologiczna jelita cienkiego i wątroby bobra europejskiego (Castor fiber). W naturalnym środowisku bobry mają stały kontakt z pasożytami wewnętrznymi i zewnętrznymi. Ocena preparatów histologicznych wykazała zmiany patologiczne w obrębie układu pokarmowego i wątroby wskazując na przewlekły stan zapalny. Założono hipotezę, że przyczyną obserwowanych patologicznych zmian w tkanek jest zapalenie wywołane pasożytami jakich wcześniej nie stwierdzano u bobrów