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1.
The granulosus subgroup of Plinthus is revised. Plinthus frivaldszkyi Davidian et Savitsky, sp. n. and P. mananauricus Davidian et Savitsky, sp. n. from the Caucasus are described. New data on the morphology and geographic distribution of P. granulosus Reitter, 1884, P. abdurakhmanovi Davidian, 1995, and P. kataevi Davidian, 1992 and a key to five species of the granulosus subgroup are presented.  相似文献   

2.
Although light trap can be used to control pest populations, they can also kill the natural enemies of pests. Scleroderma guani (Hymenoptera: Bethylidae) is a parasitoid of a bark-weevil Pissodes punctatus (Coleoptera: Curculionidae). To understand the phototactic behavior of S. guani, we investigated its diurnal and nocturnal behavior, then examined its phototactic response to nine monochromatic lights and to five intensities of the two most attractive lights. Our results showed that S. guani is most active during the day, while remain still in a dark room or at night. S. guani showed a positive response both to a broad spectrum of monochromatic light and total light (natural light), which implies a broad sensitivity to the light spectrum. S. guani was most sensitive to blue (450 nm) and green (549 nm) lights, suggesting its visual system composed of blue and green receptors. S. guani was least sensitive to ultraviolet (340 nm) light, which may be caused by long-term mass rearing and propagating under artificial conditions. Furthermore, low intensities elicited a positive phototactic response, while high intensities showed a decreased trend under both blue and green lights. Thus, S. guani is a phototactic insect which shows preferences for light in both color and intensity. This study suggests that light trap can only be utilized to control the adult P. punctatus during and after its peak emergence, due to the overlap in the spectral sensitivity of both pest and parasitoid adults.  相似文献   

3.
The merkli group of the weevil genus Plinthus is revised. Plinthus navarsati Davidian et Savitsky, sp. n. is described from Northeastern Turkey. New data on the morphology and geographical distribution of P. merkli Frivaldszki, 1894, P. cavazzutii Meregalli, 1985, and P. latipennis Meregalli, 1985 are given, with a key to all the four species of the merkli group.  相似文献   

4.
Studies were conducted on the host searching behavior of the larval parasitoid Cotesia sesamiae (Cameron) (Hymenoptera: Braconidae) and the pupal parasitoid Dentichasmias busseolae Heinrich (Hymenoptera: Ichneumonidae), both of which attack lepidopteran (Crambidae, Noctuidae) cereal stemborers. The behavior of D. busseolae was observed in a diversified habitat that consisted of stemborer host plants (maize, Zea mays L. and sorghum, Sorghum bicolor (L). Moench (Poaceae)) and a non-host plant (molasses grass, Melinis minutiflora Beauv. (Poaceae)), while C. sesamiae was observed separately on host plants and molasses grass. In previous olfactometer studies, C. sesamiae was attracted to molasses grass volatiles while hboxD. busseolae was repelled. The aim of the present study was to investigate the influence of molasses grass on close-range foraging behavior of the parasitoids in an arena that included infested and uninfested host plants. Dentichasmias busseolae strongly discriminated between host and non-host plants, with female wasps spending most of the time on infested host plants and least time on molasses grass. Likewise, C. sesamiae spent more time on uninfested and infested host plants than it did on molasses grass in single choice bioassays. While on infested plants, the wasps spent more time foraging on the stem, the site of damage, than on other areas of the plant. Overall, the results indicate that presence of the non-host plant does not hinder close range foraging activities of either parasitoid.  相似文献   

5.
The taxonomic composition of the subgenus Caucasoplinthus Davidian, 1995 is revised. The immunis and granulosus groups are downgraded to subgroups of the silphoides and fallax groups, respectively; the voriseki subgroup is transferred from the fallax to the fausti group. Plinthus attilai Davidian et Savitsky, sp. n. and P. ljudae Davidian et Savitsky, sp. n. are described from Turkey and Abkhazia, respectively. New data on the taxonomy, distribution, and ecology of some little-known species are presented. The following new synonymy is established: Molytes vittatus Motschulsky, 1839 (= Meleus irroratus Reitter, 1884, syn. n., = Meleus faldermanni Faust, 1884, syn. n., = Meleus difficilis Faust, 1884, syn. n.).  相似文献   

6.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

7.
8.
The scolytid ambrosia beetles Xyleborus monographus and X. dryographus were investigated to identify their nutritional ambrosia fungi. The examination of the oral mycetangia of the beetles, the specialized organs for fungal transport, revealed the dominant occurrence of Raffaelea montetyi, a fungus that was also predominant in the beetle tunnels in the immediate vicinity of the feeding larvae. R. montetyi was previously known only as the ambrosia fungus of the platypodid ambrosia beetle, Platypus cylindrus. These beetle species inhabit the same habitat, mainly trunks of oaks in the Western Palaeartic. The possibility of an exchange of the symbiotic fungus between the ambrosia beetles within their common breeding place is discussed. Consequently, the previous hypothesis of a species-specific association of a single ambrosia fungus with a single beetle species is questioned. A phylogenetic analysis based on DNA sequences classified R. montetyi within the Ophiostomatales of the ascomycetes. The investigation of conidiogenesis of R. montetyi by SEM supported this taxonomic placement and showed the development of the conidia by annellidic percurrent proliferation, identical to the conidiogenesis reported for many anamorph states of the Ophiostomatales.  相似文献   

9.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

10.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.  相似文献   

11.
The effects of feeding on root by the larvae and three types of Momordica cochinchinensis Spreng (Cucubitaceae) leaves (young, mature and senescent) by the adults of Aulacophora foveicollis Lucas (Coleoptera: Chrysomelidae) were studied under laboratory conditions. Total larval developmental time was 19.7 ± 0.2 days by feeding on young roots. Adult males lived for 28.4 ± 1, 65.7 ± 1.1 and 22.8 ± 1.3 days on young, mature and senescent leaves, respectively; whilst adult females lived for 34.3 ± 1.2, 68.5 ± 0.9 and 26.4 ± 1.4 days on young, mature and senescent leaves, respectively. Fecundity was highest in mature leaves fed insects (202.2 ± 10.6). Total carbohydrate, protein, lipid, nitrogen and amino acid were much higher in root followed by mature leaves than young and senescent leaves. Moisture content was highest in mature leaves than the roots, young and senescent leaves. Phenols were greatest in young leaves followed by mature leaves and least in senescent leaves and roots of the said plant. Flavonols were higher in young leaves and least in root. These results suggest that A. foveicollis adults perform better on mature leaves than young and senescent leaves for their nutrition.  相似文献   

12.
Dastarcus helophoroides adults, a coleopteran parasitoid of Monochamus alternatus, were reared in the laboratory. The objectives of this paper are to investigate the host foraging behavior of D. helophoroides, and the evidence for learning in such behaviors. Choice and no-choice experiments were carried out. The choice experiments show that the number of D. helophoroides adults choosing the Pinus massoniana log infested with M. alternatus larvae was significantly higher than that choosing the blank (a flavorless simulative log made of brown kraftpaper), and the number of D. helophoroides adults choosing the uninfested P. massoniana log was also significantly higher than that choosing the blank. The no-choice experiment shows no significant difference between the number of D. helophoroides adults that chose the infested log and that chose the uninfested log, despite previous experience with uninfested log, infested log, or neither of them. No evidence of learning in host foraging behavior in D. helophoroides adults was found. The results indicate that the volatile chemicals emitted by uninfested P. massoniana logs and infested logs with M. alternatus larvae are equally attractive to D. helophoroides.  相似文献   

13.
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.  相似文献   

14.

Background

Gonadotropin releasing hormone (GnRH) is responsible for stimulation of gonadotropic hormone (GtH) in the hypothalamus-pituitary-gonadal axis (HPG). The regulatory mechanisms responsible for brain specificity make the promoter attractive for in silico analysis and reporter gene studies in zebrafish (Danio rerio).

Results

We have characterized a zebrafish [Trp7, Leu8] or salmon (s) GnRH variant, gnrh 3. The gene includes a 1.6 Kb upstream regulatory region and displays the conserved structure of 4 exons and 3 introns, as seen in other species. An in silico defined enhancer at -976 in the zebrafish promoter, containing adjacent binding sites for Oct-1, CREB and Sp1, was predicted in 2 mammalian and 5 teleost GnRH promoters. Reporter gene studies confirmed the importance of this enhancer for cell specific expression in zebrafish. Interestingly the promoter of human GnRH-I, known as mammalian GnRH (mGnRH), was shown capable of driving cell specific reporter gene expression in transgenic zebrafish.

Conclusions

The characterized zebrafish Gnrh3 decapeptide exhibits complete homology to the Atlantic salmon (Salmo salar) GnRH-III variant. In silico analysis of mammalian and teleost GnRH promoters revealed a conserved enhancer possessing binding sites for Oct-1, CREB and Sp1. Transgenic and transient reporter gene expression in zebrafish larvae, confirmed the importance of the in silico defined zebrafish enhancer at -976. The capability of the human GnRH-I promoter of directing cell specific reporter gene expression in zebrafish supports orthology between GnRH-I and GnRH-III.
  相似文献   

15.
16.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

17.
Single (unpaired) vegetative cells of freshwater pennate diatom Neidium cf. ampliatum differentiated into gametangia and produced a single zygote (auxospore) via a pedogamic process. The gametic nuclei fused after auxospore expansion had begun. The auxospore expanded in parallel to the apical axis of the gametangium.  相似文献   

18.
Insect parasitoids use host kairomone to detect their hosts. However, in parasitoid species that attack adult hosts, the mobility of adult insect may mean that the host can move away for kairomone sources. The effect of Listronotus oregonensis LeConte (Coleoptera: Curculionidae) adult sex, feces and movement on host selection behavior by Microctonus’’ hyperodae Loan (Hymenoptera: Braconidae; Euphorinae) females was evaluated in the laboratory. We hypothesized that, in addition of using host kairomones, parasitoids of adult stage should use host movement for host selection. The sex of L. oregonensis did not affect the host selection behavior of M. hyperodae. However, host feces decreased the number of weevil antennations done by M. hyperodae. Microctonus hyperodae stopped less frequently near immobile L. oregonensis than near walking ones and these latter were frequently pursued by M. hyperodae. Host movement was the stimulus that elicited oviposition by M. hyperodae. The adaptive implications of these results are discussed.  相似文献   

19.
A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.  相似文献   

20.
Lin X  Minamisawa N  Takechi K  Zhang W  Sato H  Takio S  Tsukaya H  Takano H 《Planta》2008,228(4):601-608
ANGUSTIFOLIA (AN), a plant homolog of C-terminal binding protein, controls the polar elongation of leaf cells and the trichome-branching pattern in Arabidopsis thaliana. In the present study, degenerate PCR was used to isolate an ortholog of AN, referred to as LgAN, from larch (Larix gmelinii). The LgAN cDNA is predicted to encode a protein of 646 amino acids that shows striking sequence similarity to AN proteins from other plants. The predicted amino acid sequence has a conserved NAD-dependent 2-hydroxy acid dehydrogenase (D2-HDH) motif and a plant AN-specific LxCxE/D motif at its N-terminus, as well as a plant-specific long C-terminal region. The LgAN gene is a single-copy gene that is expressed in all larch tissues. Expression of the LgAN cDNA rescued the leaf width and trichome-branching pattern defects in the angustifolia-1 (an-1) mutant of Arabidopsis, showing that the LgAN gene has effects complementary to those of AN. These results suggest that the LgAN gene has the same function as the AN gene.  相似文献   

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