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1.
Macrodasyceras hirsutum Kamijo is the seed parasitoid wasp of the bird-dispersed, dioecious tree, Ilex integra Thunb. The wasp reduces the level of dispersal mutualism between the Ilex tree and its frugivorous birds by manipulating the color of mature berries. The female trees do not blossom every year and sometimes change sex. Thus, the reproduction biology of I. integra affects the population size and structure of M. hirsutum in a forest and consequently influences the seed dispersal mutualism between the tree and birds, because of limited ability of adult locomotion. To investigate the wasp population structure with reference to the dispersal mutualism between trees and birds, we isolated 14 microsatellite loci of M. hirsutum wasps. Every locus was polymorphic among 20 females, with 3–13 alleles per locus, without linkage disequilibrium. The observed and expected heterozygosities ranged from 0.100 to 0.900 and 0.099 to 0.818, respectively, indicating their utility in molecular analyses of the wasp population.  相似文献   

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The morphological and genetic studies of the tlb mutant of common buckwheat Fagopyrum esculentum from the collection of the All-Russia Research Institute of Legumes and Groat Crops have demonstrated that gene TLB controls an important stage of flower development—it determines the lower boundary of simple perianths. The loss of TLB gene function leads to changes in the structure of the bract from scale-like to tepal-like. Gene TLB is assumed to limit, on the basal side, the region of the expression of genes determining the development of flower organs as petals.  相似文献   

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Pathogenicity of Candida albicans is associated with its capacity switch from yeast-like to hyphal growth. The hyphal form is capable to penetrate the epithelial surfaces and to damage the host tissues. Therefore, many investigations have focused on mechanisms that control the morphological transitions of C. albicans. Recently, certain studies have showed that non-albicans Candida species can reduce the capacity of C. albicans to form biofilms and to develop candidiasis in animal models. Then, the objective of this study was to evaluate the effects of Candida krusei and Candida glabrata on the morphogenesis of C. albicans. Firstly, the capacity of reference and clinical strains of C. albicans in forming hyphae was tested in vitro. After that, the expression of HWP1 (hyphal wall protein 1) gene was determined by quantitative real-time PCR (polymerase chain reaction) assay. For both reference and clinical strains, a significant inhibition of the hyphae formation was observed when C. albicans was incubated in the presence of C. krusei or C. glabrata compared to the control group composed only by C. albicans. In addition, the culture mixed of C. albicans-C. krusei or C. albicans-C. glabrata reduced significantly the expression of HWP1 gene of C. albicans in relation to single cultures of this specie. In both filamentation and gene expression assays, C. krusei showed the higher inhibitory activity on the morphogenesis of C. albicans compared to C. glabrata. C. krusei and C. glabrata are capable to reduce the filamentation of C. albicans and consequently decrease the expression of the HWP1 gene.  相似文献   

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The genus Jatropha (Euphorbiaceae) contains species that are of significant economic and ornamental value. However, Jatropha breeding material is rather limited due to incomplete information regarding phylogenetic relationships among germplasm resources. Phylogenetic analyses were performed based on the internal transcribed spacer of nuclear ribosomal DNA (nrDNA ITS), two chloroplast regions (trnL-F and rbcL), and the combined (ITS+trnL-F+rbcL) dataset among twenty-five specimens representing six key Jatropha species. Phylogenetic relationships of Jatropha were well resolved between subgenus Curcas and subgenus Jatropha, and demonstrated the intermediate position of section Polymorphae among sections of both subgenera. Jatropha curcas and J. integerrima demonstrated a close phylogenetic relationship. The molecular data agreed with the morphological classification that recognized J. multifida and J. podagrica in sec. Peltatae. The distinct intraspecific divergence that occurred in J. curcas could be attributed to restricted gene flow caused by geographical isolation and different ecological conditions. Phylograms produced with trnL-F and rbcL sequence data suggested slow rates of sequence divergence among Jatropha spp., while the ITS gene tree had good resolution suggesting high genetic variation of ITS among Jatropha species.  相似文献   

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There is an enormous diversity in the structure of the flower palate of the carnivorous rootless genus Utricularia. This study aims to examine the structure of the palates in Utricularia bremii Heer and U. minor L of the Utricularia sect. Utricularia, which have a glandular palate type. In both species, the palate has only one type of glandular trichomes. Because of the occurrence of cell wall ingrowths in its glandular cells, any exudation may be transported via eccrinous secretion. It was proposed that the palate trichomes of the examined species act as scent glands and that the palate may play a role as an unguentarium. Both U. bremii and U. minor are of an open flower type. Thus, U. bremii and U. minor flowers can be penetrated by small, weak insects, which then easily have access to their generative structure. Small Hymenoptera (member of families Mymaridae and Braconidae) were observed as flower visitors of the male-sterile species Utricularia bremii.  相似文献   

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Bamboo flowering owns many unique characteristics and remains a mystery. To investigate the molecular mechanisms underlying flower development in bamboo, a petal-identity gene was identified as a PISTILLATA homologue named BoPI from Bambusa oldhamii (bamboo family). Expression analysis showed that BoPI was highly expressed in flower organs and gradually increased during flower development stage, suggesting that BoPI played an important role in flower development. Ectopic expression of BoPI in Arabidopsis caused conversion of sepals to petals. 35S::BoPI fully rescued the defective petal formation in the pi-1 mutant. BoPI could interact with BoAP3 protein in vitro. These results suggested that BoPI regulated flower development of bamboo in a similar way with PI. Besides flower organs, BoPI was also expressed in leaf and branch, which revealed that BoPI may involve in leaf and branch development. Similar to other MIKC-type gene, BoPI contained the C-terminal sequence but its function was controversial. Ectopic expression of the C-terminal deletion construct (BoPI- ΔC) in Arabidopsis converted sepals to petals; BoPI- ΔC interacted with BoAP3 on yeast two-hybrid assay, just like the full-length construct. The result implied that the C-terminal sequence may not be absolutely required for organ identity function in the context of BoPI.  相似文献   

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Tuber huidongense and T. liyuanum are common commercial white truffles in China that belong to the Rufum and Puberulum groups of the genus Tuber, respectively. Their mycorrhizae were successfully synthesized with two native trees—Castanea mollissima and Pinus armandii—under greenhouse conditions. The identities of the mycorrhizae were confirmed through internal transcribed spacer (ITS) sequence analyses, and their morphological characteristics were described. All of the obtained mycorrhizae have an interlocking pseudoparenchymatous mantle, which is a typical feature of truffle mycorrhizae. The mycorrhizae of T. huidongense on the two trees have hyaline branched emanating hyphae, similar to the documented mycorrhizae of the Rufum group. The unramified, spiky, and hyaline cystidia on the mycorrhizae of T. liyuanum with both C. mollissima and P. armandii further confirmed that this characteristic is constant for the mycorrhizae of the Puberulum group. The successful mycorrhizal syntheses on the two nut-producing trees will be of economic importance in the cultivation of the two truffles.  相似文献   

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Cyclamen purpurascens is considered suitable for horticultural breeding of cyclamens because it has an attractive fragrance that is not found in other wild species. To improve the commercial value of cyclamen flowers, this fragrance has been introduced into ornamental cultivars. However, variation in flower color is somewhat limited in these cultivars, and therefore understanding the genetic networks of flower coloration in C. purpurascens is required. We previously isolated DNA fragments of anthocyanin biosynthetic genes from C. purpurascens, broadening our understanding of the biosynthetic pathway of flavonols, which are co-pigments in flower coloration. In this study, we isolated complete open reading frames of flavonol synthase genes from C. purpurascens (CpurFLS1 and CpurFLS2) and analyzed the in planta functions of the genes by molecular complementation assay using the fls mutant of Arabidopsis thaliana. Expression patterns in several organs of C. purpurascens were also determined. The results strongly suggest that the CpurFLS genes participate in flavonol synthesis. We discuss the involvement of these two FLSs in flower coloration in C. purpurascens.  相似文献   

13.
During the spring and summer of 2014 and 2015, wheat and barley fields in the Iranian provinces of Golestan and Alborz showed a high incidence of symptoms of black (sooty) head mold of wheat and barley. The isolation results revealed that Alternaria was associated with these symptoms. One hundred and forty isolates were collected and morphologically characterized based on the development of conidial chains with primary, secondary, and tertiary branching patterns, consistent with the three-dimensional sporulation complexity of members of Alternaria in sections Infectoriae and Pseudoalternaria. Subsequently, 16 Alternaria isolates exhibiting high morphological diversity were characterized based on extensive morphological and molecular comparisons. Phylogenetic analyses of three loci [ITS, glyceraldehyde 3-phosphate dehydrogenase (gpd), and plasma membrane ATPase (ATPase)] revealed that 15 isolates belonged to section Infectoriae but could not be assigned to phylogenetic species and one isolate represents a new species, Alternaria kordkuyana sp. nov., in section Pseudoalternaria. Morphological assessments revealed a high degree of variation among section Infectoriae isolates and that A. kordkuyana has significant morphological differences as compared to the three other species currently described in section Pseudoalternaria.  相似文献   

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Hybridization between alien and native species is biologically very important and could lead to genetic erosion of native taxa. Solidago × niederederi was discovered over a century ago in Austria and described by Khek as a natural hybrid between the alien (nowadays regarded also as invasive) S. canadensis and native S. virgaurea. Although interspecific hybridization in the genus Solidago is considered to be relatively common, hybrid nature of S. × niederederi has not been independently proven using molecular tools, to date. Because proper identification of the parentage for the hybrid Solidago individuals solely based on morphological features can be misleading, in this paper we report an additive polymorphism pattern expressed in the ITS sequences obtained from individuals representing S. × niederederi, and confirm the previous hypothesis that the parental species of this hybrid are S. canadensis and S. virgaurea. Additionally, based on variability at the cpDNA rpl32-trnL locus, we showed that in natural populations hybridization occurs in both directions.  相似文献   

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Bruguiera hainesii (Rhizophoraceae) is one of the two Critically Endangered mangrove species listed in the IUCN Red List of Threatened Species. Although the species is vulnerable to extinction, its genetic diversity and the evolutionary relationships with other Bruguiera species are not well understood. Also, intermediate morphological characters imply that the species might be of hybrid origin. To clarify the genetic relationship between B. hainesii and other Bruguiera species, we conducted molecular analyses including all six Bruguiera species using DNA sequences of two nuclear genes (CesA and UNK) and three chloroplast regions (intergenic spacer regions of trnL-trnF, trnS-trnG and atpB-rbcL). For nuclear DNA markers, all nine B. hainesii samples from five populations were heterozygous at both loci, with one allele was shared with B. cylindrica, and the other with B. gymnorhiza. For chloroplast DNA markers, the two haplotypes found in B. hainesii were shared only by B. cylindrica. These results suggested that B. hainesii is a hybrid between B. cylindrica as the maternal parent and B. gymnorhiza as the paternal one. Furthermore, chloroplast DNA haplotypes found in B. hainesii suggest that hybridization has occurred independently in regions where the distribution ranges of the parental species meet. As the IUCN Red List of Threatened Species currently excludes hybrids (except for apomictic plant hybrids), the conservation status of B. hainesii should be reconsidered.  相似文献   

16.
The hybrid origin of Miscanthus purpurascens has previously been proposed, primarily because of its intermediate morphology. In this study, phylogenies based on the DNA sequences from the internal transcribed spacer region of nuclear ribosomal DNA (nrDNA ITS), on the DNA sequences of the trnL intron and trnL-F intergenic spacer of chloroplast DNA, and on amplified fragment length polymorphism (AFLP) fingerprinting confirm that M. purpurascens originated through homoploid hybridization between M. sinensis and M. sacchariflorus. Two different types of ITS sequences were identified from almost all plants of M. purpurascens. One type was found to be closely related to M. sinensis and the other to M. sacchariflorus. Miscanthus purpurascens was found to possess many M. sinensis- and M. sacchariflorus-specific AFLP bands but no band specific to itself. Clustering with the Unweighted Pair Group Method with Arithmetic Mean and principal coordinate analysis based on the AFLP data also demonstrated that M. purpurascens is an approximate intermediate of the two species. In addition, M. purpurascens has the plastid genome of M. sinensis or M. sacchariflorus, suggesting that either species could be its maternal parent. All specimens of M. purpurascens and its coexisting parental species are identified as diploids (2n = 2x = 38). Possible mechanisms of natural hybridization, hybrid status, chloroplast DNA recombination, and evolutionary implications of this hybridization are also discussed.  相似文献   

17.
The present study is aimed to identify genetic variability between two species of Amaranthus viz., A. caudatus and A. hybridus subsp. cruentus, two economically important species, cultivated mainly for grain production. Karyomorphological studies in Amaranthus are scarce, probably due to higher number of small sized chromosomes. Karyomorphological studies were conducted using mitotic squash preparation of young healthy root tips. Karyological parameters and karyotypic formula were established using various software programs and tabulated the karyomorphometric and asymmetry indices viz., Disparity index, Variation coefficient, Total forma percentage, Karyotype asymmetry index, Syi index, Rec index, Interchromosomal and Intrachromosomal asymmetry index and Degree of asymmetry of karyotypes. The mitotic chromosome number observed for A. caudatus was 2n = 32 with a gametic number n = 16 and A. hybridus subsp. cruentus was 2n = 34 with a gametic number n = 17. In A. caudatus the chromosome length during somatic metaphase ranged from 0.8698 to 1.7722 μm with a total length of 39.1412 μm. In A. hybridus subsp. cruentus the length of chromosome ranged from 0.7756 to 1.9421 μm with a total length of 44.9922 μm. Various karyomorphometry and asymmetry indices analyzed revealed the extend of interspecific variation and their evolutionary status.  相似文献   

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Identification of the fungus Fusarium oxysporum f. sp. pisi (Fop), the causal organism of wilt disease of pea, is a time consuming and arduous task. Diagnosis of Fop by traditional means requires more than 2 months and involves two steps, identification of species using morphological characters and formae specialispisi’ using pathogenicity assays. The ambiguous morphological differences between F. solani and F. oxysporum further complicate the diagnosis of F. oxysporum. A polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) based method was developed to detect Fop from India. A PCR–RFLP marker, HPACAPS1380, generated after restriction of 28S rDNA region with enzyme MvaI, detected accurately the Fop among several other fungi with detection sensitivity of 5 fg of Fop genomic DNA. In a mixture of Fop and pea DNA, the sensitivity was 500 pg of Fop DNA in 50 ng of pea DNA. The assay was further refined to detect the Fop from infected tissues and infested soil. The current assay can detect Fop from culture, plant tissues and soil in a considerably shorter period of time compared to traditional methods.  相似文献   

20.
Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.  相似文献   

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