The available data referring to the occurrence and geographical distribution of the females and males, the host range, the virus vector capability and the monitoring of Thrips tabaci Lindeman, as well as susceptibility and resistance of cultivars of some cultivated plant species are discussed.
Thysanoptera species were collected from Stellaria media in autumn, winter and spring in different biotopes, in Hungary. The total number of the sampled specimens was 5121. The most frequent species were (in order of frequency): Thrips tabaci, T. atratus, Frankliniella intonsa, Aptinothrips rufus, T. minutissimus, T. nigropilosus and Anaphothrips obscurus. The number of species as well as the composition of the species occurring on S. media depends on the characteristics of biotopes. The number of species considerably increased in spring from 15 to 43. Among them seven species occurred from autumn through winter till spring. S. media provides a suitable site for winter refuge, and an alternative food source for a few species, which hibernate under bark, fallen leaves and dry grass as well as in the soil, leaving their winter quarters move and accumulate temporarily on this plant. Specimens of T. tabaci capable of harbouring tomato spotted wilt virus occurred in every investigated biotopes.
Two invasive spider mite species (Stigmaeopsis nanjingensis Ma and Yuan, 1980 and Schizotetranychus bambusae Reck, 1941) were spotted on bamboo collections in Hungary. The possibilities of biological control were investigated on these mites with two different predatory mite species (Phytoseiulus persimilis Athias-Henriot, 1957 and Hypoaspis miles Berlese, 1892 [Stratiolaelaps scimitus Womersley, 1956]). The species Phytoseiulus persimilis consumed larger amount of S. bambusae mites than Stratiolaelaps scimitus mites and none of the predatory mite species could consume the S. nanjingensis species with its special nets.
Even if plants can contain high levels of nitrate and nitrite, milk and dairy products are not described as sources of these anions. The purpose of this paper was to measure the concentrations of nitrate and nitrite in forage, cow blood, and milk.The results show that the nitrate ratio of milk to plasma is very low, suggesting that milk contamination with nitrate is unlikely to occur. This finding also proves the lack of an active transport mechanism to transfer nitrate from blood to milk. The nitrite anion almost disappears from milk through an enzymatic conversion; usually levels of μg l−1 were measured.
Ecological background of the dissimilar ways of the spread of
tomato spotted wilt virus
(TSWV) was investigated in the fields in tobacco stands and in the greenhouses in forced green pepper and tomato cultures, under continental climatic conditions in Hungary.
The first version of the map of the Hungarian vegetation-based landscape regions were prepared at the scale of 1: 200,000 (1 km or higher resolution). The primary goal of the map was to provide an exact background for the presentation and evaluation of the data of the MÉTA database. Secondly, we intended to give an up-to-date and detailed vegetation-based division of Hungary with a comprehensive nomenclature of the regions. Regions were primarily defined on the basis of their present zonal vegetation, or their dominant extrazonal or edaphic vegetation. Where this was not possible, abiotic factors that influence the potential vegetation, the flora were taken into consideration, thus, political and economical factors were ignored. All region borders were defined by local expert botanists, mainly based on their field knowledge. The map differs in many features from the currently used, country-wide, flora-or geography-based divisions in many features. We consider our map to be temporary (i.e. a work map), and we plan to refine and improve it after 5 years of testing.