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1.
The scale insect Marchalina hellenica (Gennadius) (Hemiptera: Margarodidae) contributes to the production of pine honey in Turkey and Greece via the honeydew excreted when it feeds on pine trees. Although it is an insect of prime economic importance, there is no information on its genetic structure. Preliminary data were obtained based on sequencing analysis of 12s rDNA and COI mtDNA gene segments from samples from four areas of Turkey. Sequences of the 12s rDNA gene segment from Greek samples available in GenBank were also included. No variability was detected concerning the COI mtDNA gene segment analysis, although 13 haplotypes were revealed based on the 12s rDNA gene segment. The most distant population was from Mudanya-Bursa Province (Turkey). Further research is necessary on the genetic structure and variability of M. hellenica populations from the two neighboring countries.  相似文献   

2.
Marchalina hellenica (Gennadius) (Hemiptera: Margarodidae) is a scale insect, endemic in pine (Pinus halepensis) forests of Greece and other Mediterranean countries, which plays a major role in the production of honeydew honey. We investigated the morphological and the biological characteristics of M. hellenica in the pine forests of Mt. Parnis in comparison with those in the high-altitude fir (Abies cephalonica) forest of Mt. Helmos where it has been recently established, after anthropogenic intervention. Morphologically, the final body size of the 1st instar and the adult stages of M. hellenica in the fir forest were equal to those in the pine forest. Biologically, in the fir forest, the insect exhibited a long 1st instar’s period, which was the stage of its overwintering. In the pine forest, the 1st instar period was short and the insect overwinters in the stage of 2nd instar. The number of eggs per female in the fir forest was quite low (25–145) compared with the number of eggs in the pine forest (200–300). Concerning the qualitative parameters of the resulting honeydew-honey, statistically significant differences were found in Diastase and HMF (p < 0.0001). No difference was found in sucrose, fructose + glucose and water content, neither to electrical conductivity and total acidity. All values were within the EU limits (EU Directive 2001).  相似文献   

3.
The spermiogenesis, the sperm structure and the sperm motility of Marchalina hellenica (Gennadius) were examined. In the early spermiogenesis a centriolar apparatus was identified, but this structure is not involved in the production of the sperm flagellum. As in other Coccoidea, the flagellar axoneme originates by the activity of the thickened tip of the numerous microtubules surrounding the nuclear anterior region close to the periphery of the cell. This region pushes against a narrow cytoplasmic layer, giving rise to a papilla. In this region a novel structure, consisting of a regular network of thin filaments, arranged orthogonally to the bundle of microtubules, is visible. The sperm flagellum consists of a series of about 260 microtubules, regularly arranged in rings around the axial nucleus. This latter extends in the middle part of the sperm length. As usual in scale insects, sperm form a bundle, which in M. hellenica is composed of 64 sperm cells, surrounded by somatic cyst cells. The sperm bundle has an helicoidal array, with a cap of dense material at its apex, lending the anterior and the posterior region of the sperm bundle with a different structural organization. This difference is responsible of the different speed gradient observed in the helical wave propagating along the sperm bundle.  相似文献   

4.
Szklarzewicz, T., Kalandyk‐Kolodziejczyk, M., Kot, M. and Michalik, A. 2011. Ovary structure and transovarial transmission of endosymbiotic microorganisms in Marchalina hellenica (Insecta, Hemiptera, Coccomorpha: Marchalinidae). —Acta Zoologica (Stockholm) 00 :1–9. The paired ovaries of Marchalina hellenica are composed of about 200 ovarioles of telotrophic type. In each ovariole, a trophic chamber, vitellarium and ovariolar stalk can be distinguished. The tropharia comprise trophocytes and early previtellogenic oocytes (termed arrested oocytes) or trophocytes only. The arrested oocytes are not capable of further development. In the vitellaria, single oocytes develop that are connected to the tropharium by means of broad nutritive cords. The number of germ cells (trophocytes and oocytes) constituting ovarioles is not constant and may range between 25 and 32. Numerous endosymbiotic bacteria occur in the cytoplasm of trophocytes. The endosymbionts are transported via nutritive cords to the developing oocyte. The obtained results are discussed in a phylogenetic context.  相似文献   

5.
Hemicycliophora hellenica n. sp. is described and illustrated from a bisexual population found in Filippias, Epirus, Greece, in the rhizosphere of giant reed (Arundo donax) and unidentified aquatic plants along the edge of irrigation canals. Hemicycliophora hellenica n. sp. is characterized by a long stylet (more than 120 µm), body length (L = 1,078-1,634 µm; R = 303-362), and lateral field marked by three lateral lines in females and four in males. The lip region is distinctive in that the female labial disc is oval and offset from the first lip region annule, and protrudes markedly; the male labial disc is very large, offset and rectangular, and protrudes distinctly. Hemicycliophora hellenica n. sp. resembles H. megalodiscus Loof by possession of a strongly protruding labial disc, but differs in having a longer female body, more body annules, longer stylet, and dorsally and ventrally indented head annules. The male labial plate is larger than in H. megalodiscus, and the male has four incisures in the lateral field vs. three in H. megalodiscus.  相似文献   

6.
Life cycle variation of Myzus persicae (Hemiptera: Aphididae) in Greece   总被引:1,自引:0,他引:1  
During the years 1995-1999 the life cycle category of 2797 clones of Myzus persicae (Sulzer) was examined. The clones originated from primary and secondary hosts from different localities of North and Central Greece and the island of Crete in the south. Four different overwintering life cycle strategies were found that have also been described for M. persicae and other heteroecious species previously. A geographical variation was found in the proportion of holocyclic clones from tobacco and other secondary hosts associated with the abundance of the primary host in the sampling regions. In Central Macedonia, around the main peach-growing regions, the proportion of holocyclic clones was mostly above 50% and in some cases reached 100%. In localities of East Macedonia, holocyclic clones were also frequent. On the other hand, further south or in north-eastern Greece, where peach is not common, the proportion of holocyclic clones varied between 0 and 33%. Fifty seven percent of examined anholocyclic clones produced males under short day conditions, suggesting that androcyclic clones in Greece represent an important factor of genetic variability. Intermediate clones were sampled from all host-plants but at low frequencies (3.6% of total examined clones and 6.9% of non-holocyclic ones). Moreover, a regional variation was found in different colour forms feeding on tobacco plants. Red clones were predominant in regions where aphids overwinter parthenogenetically on weeds or winter crops. However, almost all clones from the primary host were green. The ecological aspects of life cycle variation are discussed.  相似文献   

7.
重描了双孔皮珠蚧Kuwania bipora Borchsenius, 1960 的雌成虫,首次记述和图示了各龄若虫和雄成虫的形态特征,并提供了分龄检索表。  相似文献   

8.
Morphological variation in nine characters of 157 clones of Myzus persicae (Sulzer) was examined by multivariate analysis. The clones were collected from peach, Prunus persica, the primary host and the secondary hosts tobacco, Nicotiana tabacum, cabbage, Brassica oleracea, sugarbeet, Beta vulgaris and pepper Capsicum annuum. The 156 clones originated from various regions of Greece, both in the north, where a large part of the population has an annual bisexual generation on peach, and in more southerly regions, where populations are predominantly unisexual. One clone was collected from tobacco in Caserta, Italy. All clones were laboratory-reared on potato. Canonical variate analysis, hierarchical cluster analysis and a non-parametric classification tree method both revealed morphological differences associated with the host-plant on which they were collected. The scores of the first two canonical variates separated the tobacco-feeding clones from those originating from other secondary host-plants. However, in tobacco-growing areas the tobacco-feeding form predominated in spring populations on peach, and was sometimes found on other secondary hosts. In addition, using cluster analysis, the clones from tobacco which were sampled in the most southeasterly region showed a relatively large phenotypic distance from those collected further north and west. Moreover, clonal phenotypes were affected both by host plant and by long-term parthenogenetic rearing. However, in spite of these effects, the tobacco form was generally distinguishable from aphids originating from other hosts, indicating that the difference must have a genetic basis. In separate analyses of the clones originating from secondary hosts no association was found between morphology and either life cycle category or colour. Discriminant analysis showed that 89% of 1723 specimens could be correctly classified into the two groups.  相似文献   

9.
不同地理和寄主来源的串珠镰孢的营养体亲和性研究   总被引:1,自引:0,他引:1  
选用107个采自安徽、山东、江苏、湖北等不同地区棉花、玉米、水稻的串珠镰孢Fusarium moniliforme菌株,在含KClO3培养基上诱导筛选获得抗氯酸盐、不能还原利用硝酸盐的突变株(nitmutant)1081株,在MM、NM、HM等3种不同氮源培养基上划分出nitA、nitB、nitC、nitD四种突变类型,其中nitA出现频率最高,占总体76%;nitB和nitC其次,分别占12%和10%;nitD最少,占总体2%。采用nit突变体互补型配对技术,将供试菌株分别按地理来源和分离寄主进行配对培养,测得不同寄主群体内菌株的营养体亲合群(VCGs)数为56个,然后从每个VCG中随机抽取1个样本菌株,测定不同群体间菌株的VCG同一性,发现所抽取的56个菌株分属于54个VCGs,其中来自棉花的菌株Fm1、Fm2分别与来自玉米的菌株Fm19、Fm20属于同一VCG。按地理来源测定,4个群体共测得55个VCGs,其中来自山东的菌株Fm45和来自安徽的菌株Fm16发生亲和反应,属于同一VCG;107个菌株划分为54个VCGs。结果表明,串珠镰孢菌株群体内存在丰富的VCGs多样性。经多样性分析,不同地理来源的菌株平均1.9454个组成1个VCG,其P与Shannon-Wiener多样性指数分别为0.5140和1.0365;不同寄主上分离的菌株平均1.9107个形成1个VCG,P与Shannon-Wiener多样性指数分别为0.5234和0.9048。经t测验,两个群体Shannon-Wiener多样性指数H值间差异不显著(t=0.70小于t0.05=1.98),说明两个群体的VCG多样性无显著差异,相同地区来源的菌株的遗传相似性与相同寄主来源的遗传相似性相当。  相似文献   

10.
Populations of Dalbulus maidis (DeLong and Wolcott) from the northeastern and central-southern regions of Brazil differ morphologically, suggesting that they could be genetically isolated. Here we used the random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR) technique to estimate genetic structuring of this leafhopper species among five geographically distant localities across those regions and to estimate gene flow between populations. Ten specimens were sampled per population and genotyped with RAPD markers generated from amplification with nine oligonucleotides. The percentage of polymorphic loci was 78% in relation to the total number of amplified loci, and genetic similarity either between or within populations was higher than 0.72. Cluster analysis grouped specimens from the northeastern population (Mossoró/RN) into a single group, whereas central-southern specimens were not grouped in relation to their places of origin. Overall, the genetic subdivision index (Fst) was low (or= 0.192 and Nm 相似文献   

11.
12.
Apatanian hellenica sp.u., the first European representative of this genus, is described from Greece.  相似文献   

13.
Triatominae are widely recognised for their role as vectors of Trypanosoma cruzi. One of the main biological characteristics of this subfamily is their obligate haematophagous condition. However, previous studies on Belminus herreri and Belminus ferroae suggested that cockroaches are their principal hosts in domiciles. Due to this peculiar behaviour, the aim of this study was to analyse several demographic and reproductive parameters of B. ferroae fed on three different hosts (mice, cockroaches and Rhodnius prolixus) and relate B. ferroae fitness to these alternative hosts. The cohorts were reared under constant conditions. The egg hatching rate was similar for cohorts fed on cockroaches (69.4%) and R. prolixus (63.8%), but was much lower for the cohort fed on mice (16%). The development time from the nymph to adult stage and the average age of first reproduction (α) presented lower values in the cohort fed on cockroaches, which is consistent with the higher population growth rate associated with this host. Demographic parameters [intrinsic rate of natural increase, finite rate of population growth, net reproductive rate and damping ratio] showed statistically significant differences between the cohorts. Analysis of the life history of B. ferroae revealed a higher fitness related to the cockroach. The implications of these results for the origin of the subfamily are discussed.  相似文献   

14.
15.
Aola M.  Richards 《Journal of Zoology》1985,205(2):287-295
The biology of the Australian coccinellid Rodatus major (Blackburn) and its prey, the hemipteran margarodid Monophlebulus pilosior (Maskell), are described. New predators and a new parasite of M. pilosior are recorded. Rodatus major makes use of elaborate and distinctive defensive adaptations and behaviour to protect itself from predators. They include cryptic coloration, aposematic behaviour, production of wax by larvae, production of a large, thick protective covering concealing the pupa and resembling an M. pilosior ovisac, and reflex bleeding. It is the only known coccinellid species in which both prepupa and pupa are hidden by a protective shroud of wax threads. Rodatus major has a specialized feeding behaviour. Its potential as a biological control agent is assessed. It is only the second Australian margarodid-feeding coccinellid to be studied, Rodolia cardinalis (Mulsant) being the first.  相似文献   

16.
The ground pearls comprise the scale insect family Margarodidae s. str., and are subterranean plant sucking parasites on roots of a wide variety of plants. Some ground pearls are serious destructive pests of grape vines, sugar cane, oil palms, cotton or lawn grass around the world. Both female and male development is characterised by an apodous, feeding 2nd-instar nymph, called a cyst. The cyst is primarily circular and often colourful, shiny, metallic or pearl-like, from which the common name “ground pearls” is derived. Other unique features are the strongly developed prothoracic legs for digging, the construction of a protective test from their own liquid excreta in which the cyst is enclosed and a behavioral adaptation by modification of their life-cycle to survive in adverse environmental conditions.

The 10 genera, currently include 105 species, form a monophyletic group with a worldwide distribution. First-instar nymphs and cysts are feeding instars; however, adults male and females lack mouthparts and do not feed. Species of ground pearls reproduce either bisexually or parthenogenetically, parthenogenesis is facultative in Eurhizococcus brasiliensis. Females undergo three, four or five developmental stages, while male have five. During the cyst stage, one, two or three molts may occur. Most species have a single generation each year, although development in Margarodes vitis requires three years including three instars of cysts. This revision redescribes and illustrates the type species of each genus, including Margarodes vitis (Philippi) and provides a key to the genera based on the morphology of adult females. Lectotypes of Dimargarodes medíterraneus (Silvestri), Heteromargarodes americanus Jakubski, Promargarodes sinensis Silvestri and Termitococcus carrotai Silvestri are designated. A nomenclatural change is proposed, the genus Sphaeraspis Giard, 1894 is considered to be a synonym of Margarodes Guilding, 1829. This work also provides information on the history of the group of Archaeococcoids; on the biology, economic importance and distribution of the margarodids.  相似文献   

17.
In the present article, we study the proboscidean remains from three upper Miocene localities of Northern Greece: Thermopigi (Serres), Neokaisareia (Pieria) and Platania (Drama). The material from the Turolian locality of Thermopigi includes only postcranial specimens. The morphological features of the scapula indicate the presence of the deinotheriid Deinotherium sp., whereas the rest of the specimens are morphologically distinct from Deinotherium and can be referred to Elephantimorpha indet. The material from Neokaisareia consists of a partial skeleton of a single individual and is attributed to the mammutid Mammut sp. (M. obliquelophus?). This taxon is known in Greece from the early–middle Turolian. The Platania proboscidean belongs to the tetralophodont amebelodontid Konobelodon cf. atticus. The genus Konobelodon was already present during the Vallesian of the wider area, but the lower tusk of the Platania shovel-tusker presents some morphological and metrical differences from the Vallesian representative, yet it has also smaller dimensions in its deciduous dentition than the morphologically similar Turolian specimens. The type locality of K. atticus is Pikermi (Attica, Greece), correlated to the middle Turolian, but the known biostratigraphic range of this species covers the entire Turolian. Platania is possibly correlated close to the Vallesian/Turolian boundary and the possible record of this species could document one of its earliest occurrences.  相似文献   

18.
Genotypic relationships between seven Prochloron samples isolated from different didemnid ascidian hosts collected at the Palau archipelago and Munda (Solomon Islands) and one cyanobacterial (Synechocystis) strain were determined by DNA-DNA reassociations. Thermal stability values of DNA-DNA hybrids indicate that all Prochloron samples involved are mutually very closely related and only slightly related with the Synechocystis strain. It is concluded that the Prochloron samples tested are representatives of one and the same species.  相似文献   

19.
The present work covers original information on aphids (Hemiptera: Aphidoidea) from Greece during 1995–2005. The individual aphid taxa were collected from their host plants and identified. The plant taxa were classified in two major categories: cultivated and self-sown. The cultivated ones were classified as: herbaceous, climbing and trees. The selfsown ones were classified as: annual herbaceous, annual or biennial herbaceous, biennial or perennial herbaceous, perennial herbaceous, shrubby and trees Two hundred twelve plant taxa were identified on which 105 aphid taxa were recorded. We report 391 plant taxa-aphid taxa associations from which, 190 are referred to cultivated and 201 to self-shown plant taxa. Aphis gossypii was found to infest the widest spectrum of cultivated plant taxa whereas Brachycaudus helichrysi was found to infest the widest spectrum of self-sown plant taxa. Myzus persicae was found to infest the widest spectrum of the total number of plant taxa. Information for several economically unimportant aphid taxa in the area are also presented.  相似文献   

20.
Heteraxinoides xanthophilis, a gill parasite of the spot, Leiostomus xanthurus, has an asymmetrical triangular-shaped haptor with multiple clamps situated along its edges. Clamps are usually attached consecutively to successive gill lamellae of the host. Worms accommodate during development to the gills of the particular size host. The number of clamps/mm along the haptor decreased with increased host size. Worms collected from 3 size classes of fish were significantly different in overall size at all stages of development. Clamps develop sequentially, with the younger, and eventually larger, clamps being anterior. Each successive clamp reaches an ultimate size determined by host size. The various stages (as indicated by the number of clamps present) at which the larval haptor is lost or the reproductive system develops are not affected by host size.  相似文献   

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