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
Myotropic neuropeptides were isolated from the retrocerebral complex of the stick insect, Carausius morosus, by using three HPLC steps. Bioactivity during purification was measured by heterologous bioassays monitoring the contractions of the hyperneural muscle and hindgut of the American cockroach. Additionally, fractions not active in these bioassays were tested in a homologous bioassay evoking contractions of the hindgut of C. morosus. Peptide sequence analysis and mass spectrometry yielded the following structures: Pro-Phe-Cys-Asn-Ala-Phe-Thr-Gly-Cys-NH2 (CCAP), pGlu-Thr-Phe-Gln-Tyr-Ser-His-Gly-Trp-Thr-Asn-NH2 (His7-corazonin) and Asp-Glu-Gly-Gly-Thr-Gln-Tyr-Thr-Pro-Arg-Leu-NH2 (Cam-PK-1). These neuropeptides are the first myotropins isolated from C. morosus. The most bioactive compound in the homologous bioassay, the C. morosus-hindgut assay, was CCAP., Reinhard Predel, Roland Kellner, Gerd Gäde, and Lit
Kančilové (Tragulidae) jsou málo známí obyvatelé tropických lesů západní Afriky, jižní a jihovýchodní Asie. Cílem tohoto článku je proto shrnutí všech nových informací, a to jak o jejich taxonomickém postavení mezi ostatními kopytníky, tak i o jejich vnitřním členění včetně základních charakteristik jednotlivých druhů. Následuje shrnutí jejich základní ekologie a etologie. Závěrečná část článku je pak věnována problematice jejich ochrany a přehledu jejich chovu v českých zoologických zahradách., Chevrotains or mouse deer (Tragulidae) are rarely studied inhabitants of the rainforests of Africa, south and south-east Asia. This article summarizes the latest knowledge about their taxonomy including the basic features of individual species, and describes their ecology and ethology. It also deals with conservation issues and provides a detailed survey of keeping and breeding chevrotains in Czech zoos., Jan Pluháček., and Obsahuje seznam literatury
Příspěvek přináší informace o nepůvodních savcích ostrova Sokotra a jejich vlivu na místní ekosystémy. Nejvýraznějším problémem je nadměrná pastva dobytka. Nadměrné spásání je výsledkem rostoucí početnosti populací domácích zvířat, zejména koz v důsledku zvýšené poptávky po mase, změny způsobu chovu a vymizením tradičního kočovného pastevectví. Důsledkem je pak nárůst půdní eroze, změna a destrukce původních rostlinných společenstev i úbytek populací endemických druhů živočichů. Snížení počtu koz na ostrově i změna způsobu jejich chovu jsou nutnými kroky zdejší ochrany přírody., This article presents information about the alien mammal species of Socotra Island and their impact on local ecosystems. The most important problem is overgrazing by livestock. It is a result of rising numbers of domestic animals, mainly goat populations, as a consequence of higher demand for meat, change of breeding style and the disappearance of traditional nomadic pasturage. This situation leads to increasing soil erosion, change and destruction of native plant populations and decreasing endemic animal species populations., and Josef Suchomel.
Nález kolonie mravence lužního na dubu na hrázi rybníka Vrkoč posouvá hranici recentního výskytu tohoto druhu o 15 km severozápadním směrem. Podle dosavadních terénních šetření jde o izolovanou kolonii, jejíž původ je nejasný. Obývaná lokalita se přitom velmi liší od preferovaného biotopu v podobě lesních porostů, protože jde o solitérní strom. Solitérní stromy či aleje přitom podle starších výzkumů využívá pouze 7 % kolonií tohoto druhu., A new colony of the ant species Liometopum microcephalum was found on the solitary oak tree growing on the dam of the pond Vrkoč near Pohořelice (southern Moravia). This discovery extends its recent distribution in the Czech Republic about 15 km to the north-west. The new colony is isolated and unusual in respect that only 7 % of south Moravian colonies are living on solitary trees or on trees in alleys., Antonín Krása., and Obsahuje seznam literatury
Článek se věnuje nově popsanému rodu Oreojuncus Záveská Drábková et Kirschner, který zahrnuje dva druhy - Oreojuncus trifidus a Oreojuncus monanthos. V České republice se vyskytuje pouze O. trifidus, sítina horská trojklanná, které je věnována větší pozornost. Rod Oreojuncus byl tradičně zařazován mezi sítiny (Juncus) sekce Steirochloa, avšak na základě komplexního výzkumu zahrnujícího fylogenetickou analýzu molekulárních dat a revizi morfologie byl vyčleněn jako samostatný, osmý rod čeledi sítinovitých (Juncaceae)., The new genus Oreojuncus Záveská Drábková et Kirschner has been described, with two species - O. trifidus and O. monanthos. Attention is given to the first species, which occurs in the Czech Republic. The genus Oreojuncus has been traditionally included in the Juncus sect. Steirochloa; however, complex research based on phylogenetic analysis of the molecular data and morphological revision revealed the necessity to establish this eighth genus in the Juncaceae family., and Lenka Záveská Drábková.
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
Ovsenka skalní (Chondrina avenacea) je plicnatý plž, který žije celoročně na holých vápencových skalách, kde dochází k drastickým denním i sezonním změnám ozáření, teploty, vlhkosti a také dostupnosti potravy. V článku popisujeme fyziologické a biochemické adaptivní mechanismy, které umožňují ovsenkám přežít na jejich extrémním stanovišti., Chondrina avenacea is a pulmonate snail dwelling on exposed rock walls where it experiences drastic daily and seasonal fluctuations of abiotic conditions and food availability. In this paper, we describe the physiological and biochemical adaptive mechanisms that allow the snails to survive in their extreme microhabitat., Vladimír Košťál, Jan Rozsypal, Pavel Pech., and Obsahuje seznam literatury