Problems and threats to the Caucasus forest ecosystems on the example of Castanea sativa

The Caucasus ecoregion is located between the Black and the Caspian Sea and extends from southern Russia, throughout Turkey, Georgia, Armenia, Azerbaijan up to Iran. The prominent feature of the region is high biodiversity and endemism. The outstanding biological richness made the Caucasus one of the 36 global hotspots of biodiversity. The Caucasian forest is concentrated mainly in Georgia, where the most diverse forest ecosystems are found. In the Colchis forest, Tertiary relicts are present and this area formed glacial refugium for flora and fauna. However, the region and its wildlife are now under threat. Uncontrolled logging, urban and agricultural development, and climate changes bring about the great risk for many species and unique plant assemblages. The massive decline of Castanea sativa (sweet chestnut) exemplifies the problems of the alien parasite invasions and ineffective forest management and nature conservation. Biodiversity of the Caucasus is being lost at an alarming rate that calls for urgent action and intensification of investigations aiming at better understanding of the evolutionary history of the region.

USE OF A COMMERCIAL ORGANIC PRODUCT TO CONTROL THE BLACK WEEVIL (ACLEES SP. CF. FOVEATUS) OF THE FIG TREE

A new alien parasite, Aclees sp. cf. foveatus (Coleoptera: Curculionidae), is causing considerable crop losses and deaths in many Italian fig (Ficus carica L.) tree nurseries and orchards and it is quickly spreading in central Italy. The adult and larval stages of this weevil are closely related to t he fig tree. To date, no phytosanitary products are registered for fig against this insect, so if this pest is not systematically managed, fig trees could be decimated. A commercial organic product, LaserTM, widely used on other crops, was used to assess its effectiveness on the adult stage of this weevil. In the first trial, the concentration recommended on the label for other fruit trees was used and compared with the control (only water), while in the second trial a comparison between the label concentration and the half was tested. Mortality of the adults was recorded in the following 3-4 days after treatment. A very high adult mortality was recorded when LaserTM was applied, even at lowest concentrations, and damages (erosion) on the sycons were strongly reduced compared to the control. The tested commercial product is very effective in controlling this pest and can represent a possible solution by significantly reducing the adult population.

Utilization of alien freshwater fishes by the parasitic copepod Neoergasilus japonicus (Ergasilidae) on Okinawa-jima Island, Japan, with a list of its known hosts

Currently, many fish parasites have been dispersed worldwide via the movement of fishes for food, sport, or the aquarium trade. The freshwater parasitic copepod Neoergasilus japonicus (Harada, 1930) is such an example: it is native to eastern Asia, but has been introduced to southern Asia, Europe, and North America. Since N. japonicus has been regarded as an important alien parasite in such regions, more information is needed on the ecology and host-parasite relationships of this species. In this study, specimens of N. japonicus were collected from the following seven alien freshwater fishes on Okinawa-jima Island, southern Japan: redbelly tilapia (Tilapia zillii), Mozambique tilapia (Oreochromis mossambicus), and Nile tilapia (O. niloticus niloticus) (Perciformes: Cichlidae); bluegill (Lepomis macrochirus) (Perciformes: Centrarchidae); Indian glassy fish (Pseudambassis ranga) (Perciformes: Ambassidae); mosquitofish (Gambusia affinis) (Cyprinodontiformes: Poeciliidae); and vermiculated sailfin catfish (Pterygoplichthys disjunctivus) (Siluriformes: Loricariidae). Copepods occurred on alien fishes taken from reservoirs, but were absent on those from rivers. The dorsal fin was most heavily infected, followed by the anal fin, gills, and body surface. The native freshwater fishes in our sampling locations have been replaced by alien fishes that were introduced from various regions of the world. Our results therefore showed that this low host-specific species can persist by utilizing alien fishes as hosts even after the native fishes have either disappeared or greatly decreased in abundance. A list is also given of fishes (88 species and 3 subspecies in 7 orders and 16 families) reported as hosts of N. japonicus.