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1.
为害枣树一菱纹叶蝉新种   总被引:1,自引:0,他引:1  
蔡平  崔士英 《昆虫学报》1995,38(2):217-219
为害枣树一菱纹叶蝉新种蔡平(安徽农学院园艺系合肥230036)崔士英(河北师范大学生物系石家庄050016)葛钟麟(安徽农学院植保系合肥230036)菱纹叶蝉属(Hishi。。onusIshihara。1953)隶属于同翅目(HomoPtera)n十...  相似文献   
2.
The complex flower organization of orchids offers an opportunity to discover new variant genes and different levels of complexity in the morphogenesis of flowers. In this study, four B-class Phalaenopsis DEF-like MADS-box genes were identified and characterized, including PeMADS2, PeMADS3, PeMADS4 and PeMADS5. Differential expression profiles of these genes were detected in the floral organs of P. equestris, suggesting distinctive roles in the floral morphogenesis of orchids. Furthermore, expressions of these genes were varied to different extents in the peloric mutants with lip-like petals. Expression of PeMADS4 was in lips and columns of wild type, and it extended to the lip-like petals in the peloric mutant. Expression of PeMADS5 was mainly in petals and to a lesser extent in columns in the wild type, whereas it was completely eliminated in the peloric mutant. Disruption of the PeMADS5 promoter region of the peloric mutant was detected at nucleotide +312 relative to the upstream of translational start codon, suggesting that a DNA rearrangement has occurred in the peloric mutant. Genomic structure analysis of the PeMADS5 showed that the exon length was conserved in exons 1-6, similar to DEF-like genes of other plants. Collectively, this is the first report that four DEF-like MADS genes were identified in a single monocotyledonous species and that they may play distinctive morphogenetic roles in the floral development of an orchid.  相似文献   
3.
This paper aims to achieve insight into various ecological theories in the Netherlands which have different, and sometimes opposing, views on the conservation of nature. Interviews, publications and archival research brought to light four separate theories: vitalistic/holistic, dynamic, cybernetic and chaos. Diversity is reached through stability according to vitalistic/holistic and cybernetic theories, but through change and instablility according to the dynamic and chaos theories. These two groups are working apart, and continue to have their own ideas. Prediction of the future is only possible with the vitalistic/holistic and cybernetic theories. Ecologists who adhere to these theories feel responsible and able in different ways to change ecological nature towards desirable end goals. The other two theories, dynamic and chaos, appear to be less activist.  相似文献   
4.
片叶蝉属ThagriaMelichar是离脉叶蝉亚科Coelidinae中最大的类群,全世界已知190种,主要分布于东洋区、澳洲区和古北区[1],我国记录有41种[2~5]”。该属不同于离脉叶蝉亚科其它属的显著特点在于:尾节端背缘有成对突起;阳茎简...  相似文献   
5.
徐桂兰  葛钟麟 《昆虫学报》1998,41(3):310-313
Two new species of the gensu Thagria Melichar (Cicadellidae.Coelidiinae) are described and illustrated from China. The type specimens are deposited in the Department of Plant Protection, Anhui Agricultural University, Hefei, China.  相似文献   
6.
Traditional breeding processes to genetically modify the long reproductive cycle and slow seed maturation of orchids have limits. We developed a more efficient protocol using particle bombardment to produce transgenic plants of Oncidium Sharry Baby OM8 (Orchidaceae). Pretreating protocorm-like bodies (PLBs) with 0.5 M sucrose for 2 h increased single-cell embryogenesis 3- to 4-fold; however, shoot formation was suppressed. In addition, new PLBs were regenerated from the entire sucrose-pretreated PLBs, whereas in untreated PLBs, this occurred only from the bases. Pretreated PLBs were bombarded with pSPFLP containing genes encoding a sweet pepper ferredoxin-like protein (pflp), hygromycin phosphotransferase (hpt) and -glucuronidase (GUS) driven by the cauliflower mosaic virus 35S promoter. Pretreated PLBs showed a 14.8-fold increase in GUS expression over the untreated PLBs 40days after bombardment. The presence of pflp and hpt transgenes in the 40 putatively stably transformed lines that produced 113 clones was confirmed by PCR analysis. Six lines (eight clones) were positive for both pflp and hpt transgenes. In addition, clones derived from these lines were either all positive or all negative for the two transgenes, which suggests homogeneity in pretreated PLBs with more single-cell embryogenesis. Thus, sucrose pretreatment enhanced the regeneration of PLBs, single-cell embryogenesis and efficiency of transformation.  相似文献   
7.
Geranyl diphosphate (GDP) is the precursor of monoterpenes, which are the major floral scent compounds in Phalaenopsis bellina . The cDNA of P. bellina GDP synthase ( PbGDPS ) was cloned, and its sequence corresponds to the second Asp-rich motif (SARM), but not to any aspartate-rich (Asp-rich) motif. The recombinant PbGDPS enzyme exhibits dual prenyltransferase activity, producing both GDP and farnesyl diphosphate (FDP), and a yeast two-hybrid assay and gel filtration revealed that PbGDPS was able to form a homodimer. Spatial and temporal expression analyses showed that the expression of PbGDPS was flower specific, and that maximal PbGDPS expression was concomitant with maximal emission of monoterpenes on day 5 post-anthesis. Homology modelling of PbGDPS indicated that the Glu-rich motif might provide a binding site for Mg2+ and catalyze the formation of prenyl products in a similar way to SARM. Replacement of the key Glu residues with alanine totally abolished enzyme activity, whereas their mutation to Asp resulted in a mutant with two-thirds of the activity of the wild-type protein. Phylogenetic analysis indicated that plant GDPS proteins formed four clades: members of both GDPS-a and GDPS-b clades contain Asp-rich motifs, and function as homodimers. In contrast, proteins in the GDPS-c and GDPS-d clades do not contain Asp-rich motifs, but although members of the GDPS-c clade function as heterodimers, PbGDPS, which is more closely related to the GDPS-c clade proteins than to GDPS-a and GDPS-b proteins, and is currently the sole member of the GDPS-d clade, functions as a homodimer.  相似文献   
8.
一、前言 蚕豆象是蚕豆的主要害虫,也是世界性的一种害虫。大凡温度较高湿度较大的地区,多有它的足迹,不过在我们中国,特别是在黄河流域和长江流域,在历史上尚没有见到它的为害记载,在实际上,江浙一带这虫的大量为害,也仅仅发生在抗日战争之後,江浙老农都说是日本帝国主义者带来的;大公报也曾载称,是由日军  相似文献   
9.

Background  

Floral scent is one of the important strategies for ensuring fertilization and for determining seed or fruit set. Research on plant scents has hampered mainly by the invisibility of this character, its dynamic nature, and complex mixtures of components that are present in very small quantities. Most progress in scent research, as in other areas of plant biology, has come from the use of molecular and biochemical techniques. Although volatile components have been identified in several orchid species, the biosynthetic pathways of orchid flower fragrance are far from understood. We investigated how flower fragrance was generated in certainPhalaenopsis orchids by determining the chemical components of the floral scent, identifying floral expressed-sequence-tags (ESTs), and deducing the pathways of floral scent biosynthesis inPhalaneopsis bellina by bioinformatics analysis.  相似文献   
10.
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