Muchničky jsou známy v mnoha oblastech jako trapiči člověka i dobytka, ale také jako přenášeči parazitárních onemocnění, z nichž nejvýznamnější je říční slepota. Muchnička Simulium colombaschense byla v minulosti považována za jeden z nejnebezpečnějších druhů v rámci čeledi, protože na následky napádaní samičkami tohoto druhu uhynuly na Balkánském polostrově desetitisíce kusů dobytka. V současnosti se však zdá, že může být považována za ohrožený druh, především v důsledku regulace velkých řek. Podle předběžných výsledků analýzy polytenních chromozomů představuje S. colombaschense komplex druhů s menšími areály. Typová lokalita druhu S. colombaschesne byla zničena po přehrazení Dunaje v oblasti Železných vrat a následně z této oblasti postupně zmizelo i S. colombaschense. Podobný osud může v blízké době postihnout, nebo už postihl také další blízce příbuzné druhy z tohoto komplexu., Black flies (Simuliidae) are known in several areas as pests to humans and cattle, but also as transmitters of parasitic diseases, among which river blindness is the most important. In the past, the black fly Simulium colombaschense was considered to be one of the most dangerous species of the family, because it caused the death of tens of thousands of cattle in the Balkan peninsula. However, at present it seems that it can be considered an endangered species, especially due to large river regulation. Moreover, according to preliminary analysis of polytene chromosomes S. colombaschense is a complex of species with smaller distribution areas. The type locality of S. colombaschense was destroyed after the Danube was dammed in the Iron Gate region and subsequently S. colombaschense disappeared from this area. In the near future the same might possibly happen, or has already happened as to other species from this complex., and Tatiana Brúderová, Matúš Kúdela.
Muga silkworm (Antheraea assamensis Helfer) is endemic to Assam and adjoining areas in North-Eastern India, and naturally produces golden silk. From time immemorial, many ethnic and tribal groups have produced muga silk. Muga silkworms are mostly wild unlike the mulberry silkworm, which is completely domesticated. The muga silkworm is a single species with little genetic variation among populations, survives harsh climatic conditions and is subject to various diseases, pests and predators. Due to the high incidence of disease and natural enemies, and variations in climatic conditions, the production of muga silk has recently declined dramatically. In order to improve the productivity of this silkworm it is important to have a better knowledge of both its host plants and biology. Lack of knowledge of its genetics and host plants is a major bottleneck. This paper reviews various aspects of muga silkworm culture, including the availability of different populations, and methods used to select for improvement in survival, cocoon yield, disease resistance, conservation and egg production., Amelendu Tikader, Kunjupillai Vijayan, Beera Saratchandra., and Obsahuje seznam literatury
In social insects, the high variability in the number of queens per colony raises fundamental questions about the evolution of altruism. It is hypothesized, for instance, that nestmate recognition should be less efficient in polygynous than in monogynous colonies because the presence of several breeders increases the diversity of genetically determined recognition cues, leading to a less specific colonial signature. Recent studies, however, have shown that the link between the number of queens in a colony and the recognition abilities of its members is more complex than previously suggested. Here, we studied intraspecific aggression, diversity of potential recognition cues and genetic structure of colonies in the highly polygynous ant Crematogaster pygmaea. Our results reveal that workers of this species are clearly aggressive towards non-nestmates in field experiments but not in more artificial bioassays conducted in Petri dishes, underscoring the importance of context-dependent aspects of the assessment of nestmate recognition. Behavioural, genetic and chemical data show that C. pygmaea is a multicolonial species, forming spatially restricted and well-defined entities. Therefore, the postulated negative correlation between recognition ability of workers and queen number in a colony is not supported by the results of this study., Rachid Hamidi ... [et al.]., and Obsahuje seznam literatury
Můrovití (Noctuidae) představují po obalečovitých (Tortricidae) druhou největší čeleď motýlů v České republice. Dosud bylo na našem území zaznamenáno kolem 430 druhů, ale mnohé z nich se zde nevyskytují trvale. Můrovití jsou obvykle velmi dobří a pohybliví letci, často mají tendenci kolonizovat nová území. Řada druhů žijících v jiných částech Evropy byla zaznamenána pouze v jednom nebo omezeném počtu exemplářů (zhruba 20 druhů), jiné jsou pravidelnými migranty (13 druhů), někteří zástupci se v současnosti šíří (asi 10 druhů), zatímco jiní jsou na ústupu (5–6 druhů), nebo mají proměnlivou hranici areálu. V článku naleznete příklady druhů z uvedených skupin, s diskuzí současného nebo historického stavu., Owlet moths (Noctuidae) are after leafrollers (Tortricidae) the second largest family of butterflies and moths in the Czech Republic. So far, about 430 species have been recorded, but many of them do not occur permanently in the area. Owlet moths are usually very good and highly mobile fliers, often with a tendency to colonize new territories. Some species living in other parts of Europe have been registered in only one or a limited number of individuals (about 20 species), others are regular migrants (13 species). While some species are currently spreading (about 10 species), others are retreating (5–6 species), or the boundaries of their ranges are unstable. Examples of these groups are given and discussed., and Zdeněk Laštůvka, Aleš Laštůvka.
The mechanism of sex determination is common for all honeybee species (Apis spp.) by the complementary sex determination (csd) gene. The csd gene has been studied in the Western honey bee (Apis mellifera L.), the Eastern honey bee (Apis cerana F.) and the giant honey bee (Apis dorsata F.), whereas no studies had been conducted on the high altitude Himalayan or black giant honey bee, Apis laboriosa Smith. In the present study, we cloned the genomic exon 6 to exon 9 region of the A. laboriosa csd gene, and identified 13 csd haplotypes. The data was analyzed and compared with the other aforementioned three honeybee species. The results showed that, as with the other three Apis species, region 3 of the csd gene contains an RS domain at the N terminal, a proline-rich domain at the C terminal, and a hypervariable region in the middle. A phylogenetic tree showed that the csd haplotypes from A. laboriosa fell into one clade with those from A. dorsata, and were separated from those from the other two species, A. mellifera and A. cerana. The network map also showed that the csd haplotypes from A. laboriosa and A. dorsata are well mixed among each other, and do not form two separate branches. Pairwise Fst analysis revealed that the value between A. laboriosa and A. dorsata was very low (0.098), confirming a close relationship to exist between them., Huan Wang ... [et al.]., and Obsahuje seznam literatury
Endosymbiotic organisms are known to manipulate the reproductive biology of their hosts. Incomplete prevalence of endosymbiont inducing thelytokous parthenogenesis results in the coexistence of sexual and asexual individuals, and could account for the maintenance of sexual reproduction in certain populations or species. In the parasitoid Venturia canescens, arrhenotokous ("sexual") and thelytokous ("asexual") individuals occur sympatrically. We aimed to determine whether endosymbionts are implicated in the thelytoky of V. canescens. After screening females of the two reproductive modes for several reproductive parasites: bacteria (Wolbachia, Rickettsia, Bacteroidetes, Spiroplasma, Arsenophonus) and Microsporidia, we concluded that thelytoky in V. canescens is not induced by any of these parasites and confirmed its suitability as a biological model for solving the evolutionary enigma of the maintenance of sexual reproduction., Vincent Foray ... [et al.]., and Obsahuje seznam literatury
The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of this exotic species and its seasonal abundance in various field crops. The abundance of adults, larvae and pupae of H. axyridis was evaluated over a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. From May to September, 48 1-m² quadrats were visually inspected in each of the fields sampled on several farms every seven days. H. axyridis colonized and reproduced in all of the four crops studied, with the largest numbers recorded in corn and broad bean crops. Larvae and adults of H. axyridis were recorded mainly in corn and to a much less extent in wheat and potato crops. From 2009 to 2011, the mean weekly abundance of H. ayxridis remained constant except in corn crops, where the recorded densities of all the immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis are well described by a symmetric logistic function (S-shape) of cumulative population size. H. axyridis was not always recorded where aphids were abundant, e.g. aphids were abundant on wheat where no H. axyridis were recorded. H. axyridis start reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of the same and other species of ladybird and other aphidophagous species. H. axyridis is often considered to be bivoltine but it only completes one generation per year in field crops. The second generation generally develops late in the season in other habitats., Axel Vandereycken ... [et al.]., and Obsahuje seznam literatury