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1.
Capsicum chinense is a recalcitrant species for in vitro morphogenesis, and up to date there is no efficient system for genetic transformation and regeneration of this species via somatic embryogenesis. Here, we carried out an in vitro transformation of C. chinense via Agrobacterium tumefaciens co-cultivation with a system that expresses the heterologous gene WUSCHEL from Arabidopsis thaliana. WUSCHEL has been shown to promote the transition from vegetative to embryogenic state when overexpressed. We tested if the expression of WUSCHEL in C. chinense would promote an embryogenic response in this species. After 15 days of induction, the segments of transformed stems begun to form globular structures, suggesting that heterologus WUSCHEL was active and involved in the process of morphogenesis.  相似文献   

2.
Summary  The name Pavetta modesta (Hiern) S. E. Dawson is a later homonym of P. modesta Bremek. Pavetta crystalensis is proposed as a new name.  相似文献   

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Summary   Psychotria kupensis Cheek is described as a new species in Psychotria sect. Confertiflorae Hiern. Attention is drawn to its monopodial, dwarf, litter-gathering and adventitious root-forming habit and to its anomalous stipules. The species appears to be endemic to the submontane evergeen forest of Mt Kupe in Cameroon. Its conservation status is assessed.  相似文献   

6.
Summary  A new species of Eriocaulon, E. epedunculatum (Eriocaulaceae) is described and illustrated from the Western Ghats, India.  相似文献   

7.
We performed comparative analyses of four cross-sections of the distal radius and tibia in two species of macaque to clarify the relationships between bone morphology and locomotor type. The lengths of bones and five bone geometric properties in each section were examined and compared separately in both female and male Macaca mulatta and Macaca fascicularis. In M. mulatta, there were no significant gender-specific differences in either the radius or the tibia. In contrast, the radius and tibia of male M. fascicularis had greater geometric parameters in the 20% and 40% positions relative to the 5% and 10% positions from the distal end than those of their female counterparts. The radius and tibia of M. mulatta were relatively longer than those of M. fascicularis, and the sectional parameters of the tibia of M. mulatta were relatively larger than those of M. fascicularis. Standardization of the log-transformed bone length between the species revealed larger radial cortical bone areas in M. fascicularis. In contrast, there were minimal differences in the tibial cortical bone areas between the two species. This study suggests that the observed distinctions in bone geometry in female and male M. fascicularis may be due to gender-specific differences in the muscle weights of the forearm and calf, which may underlie the divergence in the leaping abilities of females and males of this species. Taken together, these results of interspecies comparisons may be related to the fact that arboreal primates such as M. fascicularis undergo compressive mechanical stress due to the forelimb lead that occurs as the animal descends a sloping trunk or bridges a tree gap downward, while terrestrial primates such as M. mulatta move on nearly flat substrates. Differences in fore- and hind-limb bone properties between the two species are discussed with regard to functional morphology and locomotor type.  相似文献   

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Summary   Strobilanthes pothigaiensis, a new species of Strobilanthes (Acanthaceae) allied to S. foliosus T. Anderson from southern Western Ghats, India, is described and illustrated.  相似文献   

9.
We studied the oviposition performance of Fopius arisanus (Sonan) (Hymenoptera: Braconidae) attacking eggs of four fruit flies of the genus Anastrepha Schiner (Diptera: Tephritidae) under laboratory conditions. The complete process of oviposition on an individual egg of Anastrepha ludens (Loew) lasts in average 85.4 ± 2.9 s, including a tremor (25.8 ± 1.03 s) observed in the middle of this process related to the egg’s descent. The average parasitism of A. ludens egg was 60.9 ± 7.5%, with only 1.2% of superparasitized eggs. During individual acts of oviposition, we noted that F. arisanus possesses a highly flexible ovipositor that curves easily as it searches for additional suitable eggs, which may be of particular benefit when a female finds large clutches of eggs. The individual oviposition of F. arisanus in host fruits attacked by Anastrepha spp. varies with the egg clutch size of each fruit fly species: A. serpentina laid the biggest egg clutches (21.3 ± 1.4), followed by A. ludens (14.2 ± 0.9), and A. striata (1.0 ± 0.0) (=A. obliqua). The time spent by F. arisanus in individual ovipositions was parallel to these findings, reinforcing the idea that F. arisanus attacks several eggs in each individual insertion of its ovipositor. Neither formal oviposition acts, nor adult emergences of F. arisanus were registered in A. obliqua. We discuss the potential of F. arisanus as natural enemy of fruit flies of the genus Anastrepha, and explore the eventual developing of its mass rearing. Handling Editor: Torsten Meiners.  相似文献   

10.
As a step toward greater understanding of the genetics of verticillium wilt resistance in plants, we report the sequencing of a candidate wilt resistance gene, mVe1, from the mint diploid model species, Mentha longifolia (Lamiaceae). mVe1 is a putative homolog of tomato (Solanum lycopersicum L.) verticillium wilt (Ve) resistance genes. The mVe1 gene has a coding region of 3,051 bp. The predicted mVe1 protein contains a leucine-rich repeat domain, a common feature of plant disease resistance proteins. We compared 13 mVe1 alleles from three mint species. These alleles shared 96.2–99.6% nucleotide identity. We analyzed four M. longifolia populations segregating with respect to mVe1 alleles and wilt resistance versus susceptibility and found one association between mVe1 genotype and wilt phenotype. We conclude that mVe1 may play a role in mint verticillium wilt resistance, but variation for resistance in our segregating progenies is likely polygenic. Therefore, further investigations of mVe1 and identification of additional candidate genes are both warranted.  相似文献   

11.
Biological control of the cyst forming nematode Heterodera cajani was studied on sesame using plant growth promoting rhizobacteria (PGPR) Pseudomonas aeruginosa LPT3 and LPT5. Based on plant growth promoting attributes, two fluorescent pseudomonads, LPT3 and LPT5 were evaluated for their efficacy against cyst forming nematode Heterodera cajani that parasitize Sesamum indicum. Pseudomonas aeruginosa LPT5 produced IAA, HCN, chitinase, glucanase and siderophore, and also solubilized inorganic phosphate in vitro. Moreover, LPT5 resulted in mortality of second stage juveniles of H. cajani, which was 13% higher as compared to P. aeruginosa LPT3. Interestingly, when both strains were inoculated together for the management of H. cajani on Sesamum indicum the population of H. cajani was reduced significantly, in field trial. Approximately 60% reduction in cyst and juveniles population was recorded with LPT5 coated seeds, while LPT3 resulted in 49% reduction in cyst and juvenile population as compared to control. Plants grown with seeds bacterized with LPT5 and reduced doses of urea, diammonium phosphate (DAP), muriate of potash (K) and gypsum gave maximum increase in yield, in comparison to that of plants raised under the influence of recommended or full doses of the chemical fertilizers. Pseudomonas aeruginosa LPT5 also showed excellent root colonization.  相似文献   

12.
Septobasidium parviflorae sp. nov. on Pinus parviflora is described and illustrated. This species is characterized by its whitish-gray, gray to dark gray-colored fungus body with an indeterminate margin, hyphal strands, and cylindrical basidia with long sterigmata. This is the first report of Septobasidium occurring on a member of the genus Pinus in Japan.  相似文献   

13.
The architecture of the musculature of the eutardigrade species Milnesium tardigradum Doyère, 1840, Hypsibius sp. and Ramazzottius oberhaeuseri (Doyère in Ann Sci Nat Zool Sér 2(14):269–369, 1840) is investigated by phalloidin staining and confocal laser scanning microscopy. There are methodological problems in staining eutardigrades due to physiological alterations under stress (anhydrobiosis) and due to penetration problems of the cuticle. It is helpful to fix specimens in the state of asphyxy, where animals are stretched following an oxygen shortage in their environment. The musculatures of all three species correspond in their general architecture, but differ in detail, such as in the number of muscles. All muscles are isolated muscle strands. There are on each body side two dorsal and one ventral muscle strands, in addition to a system of dorsoventral, lateral and lateroventral muscles. Seven median ventral attachment points give rise to dorsoventral, ventrolateral and appendage muscles. The appendages receive several muscles originating dorsally and ventrally. The number of muscles and the arrangement differ in each appendage. The fourth appendage shows the greatest differences with a far smaller number of muscles compared to other species. The musculature shows comparably few strict segmental patterns, for example, the musculature of each appendage differs from the other ones. By comparison with literature data on the same species and data of Macrobiotus hufelandi it can be shown that eutardigrades have a roughly comparable muscular architecture, but that there are several differences in detail. Dedicated to Professor Westheide on the occasion of his 70th birthday.  相似文献   

14.
To explore the possibility of an effectively long-term preservation of the germplasm of the HR lines of medicinal plant Astragalus membranaceus, Gentiana macrophylla Pall., and Eruca sativa Mill., both cold storage and cryopreservation approaches were attempted and compared. After 5-month cold storage on half strength Murashige and Skoog (1962) (1/2 MS) agar medium (AM), up to 82.9, 75.7, and 100% of the A. membranaceus, G. macrophylla and E. sativa hairy roots (HRs) recovered growth, respectively. The survival rates of A. membranaceus and G. macrophylla HRs significantly decreased, whereas that of E. sativa HR was unchanged with the addition of increased levels of exogenous abscisic acid (ABA) during cold storage. Using the encapsulation–vitrification (EV) method for cryopreservation, the G. macrophylla HRs died, whereas up to 6 and 73% of the A. membranaceus and E. sativa HRs survived, respectively. The HR lines evaluated with both methods showed no significant differences in morphology and growth rate compared with controls that were not subjected to preservation methods. These results suggest that cold storage is a more suitable alternative for the HR lines of the three studied plant species and that specificity of plant species have profound effects on the effectiveness of preservation.  相似文献   

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In this study, the Phanerotomini of Turkey collected between July 1959 and July 2004, are listed. A total of thirteen Phanerotomini species were determined, and six of these are reported for the first time from Turkey. Phanerotoma (Bracotritoma) permixtellae Fischer, 1968 was reared from a new natural host Recurvaria pistaciicola (Danilevskii, 1955) (Lepidoptera: Gelechiidae). With this present study an illustrated identification key for the Phanerotomini of Turkey is given. The distribution of the Phanerotomini species is discussed according to the phytogeographical provinces of Turkey.  相似文献   

17.
Callus cultures derived from leaf segments of chrysanthemum cultivar ‘Snow Ball’ which was susceptible to Septoria obesa were successfully used for in vitro selection for resistance to this pathogenic fungus. Resistant cell lines were selected by culturing callus on growth medium containing various concentrations of S. obesa filtrate. Resistant calluses obtained after two cycles (30 d each cycle) of selection were used for plant regeneration. About 30% of the plants regenerated from the resistant calluses and 70–80% of the plants raised from cuttings had acquired considerable resistance against the pathogen in the field. No phenotypic variation was observed in the selected regenerates.  相似文献   

18.
Deschampsia antarctica Desv. (Poaceae), known as Antarctic hairgrass, is the only grass species and one of the two vascular plant species native to Antarctica and it is a valuable source for gene discovery associated with freezing-tolerance. In this work the karyotype of D. antarctica collected near Jubany Antarctic Base was reported for the first time. This species presents a chromosome number of 2n = 2x = 26, with karyotypic formula 10m + 6sm + 8st + 2t. The nucleolar organizer region is located in the short arm in one of the submetacentric pairs forming a terminal satellite. Aneusomaty, a phenomenon already reported in the genus, was detected during this study. The cytogenetic information, together with the recent phylogenetic data will be useful for breeding strategies in agronomically valuable crops.  相似文献   

19.
Pseudocercospora griseola is the causal agent of angular leaf spot of common bean (ALS). It has undergone parallel coevolution with its host and two major groups have been defined, “Andean” (P. griseola f. griseola) and “Mesoamerican” (P. griseola f. mesoamericana). The aim of this study was to analyze the nature and the level of the dark pigment synthesized by the representatives of each group. After 21 days of incubation on potato dextrose agar medium, P. griseola f. griseola isolate S3b developed colonies with diameters of 17.5 ± 1.3 mm and concentric rings of pigmentation. Isolate T4 of P. griseola f. mesoamericana presented smaller colonies (9.9 ± 0.3 mm) with a uniform dark-gray color. Both isolates, S3b and T4, produced the same pigment, a 1,8-dihydroxynaphthalene-melanin, although different in quantity and structural features as suggested by the IR spectrum. The P. griseola f. griseola isolate S3b had a higher growth rate and melanin content as well as smaller sensitivity to melanin synthesis inhibitors compared to the isolate T4 of P. griseola f. mesoamericana. These results suggest a possible link between melanin and growth in P. griseola.  相似文献   

20.
Activity of the VERNALIZATION1 (VRN1) gene is required for flowering in temperate cereals such as wheat and barley. In varieties that require prolonged exposure to cold to flower (vernalization), VRN1 is expressed at low levels and is induced by vernalization to trigger flowering. In other varieties, deletions or insertions in the first intron of the VRN1 gene are associated with increased VRN1 expression in the absence of cold treatment, reducing or eliminating the requirement for vernalization. To characterize natural variation in VRN1, the first intron of the barley (Hordeum vulgare) VRN1 gene (HvVRN1) was assayed for deletions or insertions in a collection of 1,000 barleys from diverse geographical regions. Ten alleles of HvVRN1 containing deletions or insertions in the first intron were identified, including three alleles that have not been described previously. Different HvVRN1 alleles were associated with differing levels of HvVRN1 expression in non-vernalized plants and with different flowering behaviour. Using overlapping deletions, we delineated regions in the HvVRN1 first intron that are associated with low levels of HvVRN1 expression in non-vernalized plants. Deletion of these intronic regions does not prevent induction of HvVRN1 by cold or the maintenance of increased HvVRN1 expression following cold treatment. We suggest that regions within the first intron of HvVRN1 are required to maintain low levels of HvVRN1 expression prior to winter but act independently of the regulatory mechanisms that mediate induction of HvVRN1 by cold during winter. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers 1179825, 1179833, 1179836, 1179858.  相似文献   

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