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1.
Puri  S.  Swamy  S.L.  Jaiswal  A.K. 《New Forests》2002,23(1):45-61
Populus deltoides Bartr., a native of North America, is generally grown in India above latitude 28 °N. One hundred and six clones were evaluated for four years at Raipur situated at 21°12N latitude and 81°36E longitude. These were grown on vertisol soil. Based on growth and survival performance in the nursery for two successive years, nineteen clones were selected for field evaluation. The best five clones (G3, G48, 65/27, D121 and S7C1) were planted in an agrisilviculture system at a spacing of 4 × 4 m with soybean grown as an intercrop. After 4 years these clones had an increment of DBH by 66.5 to 77.5% and of height by 42.2 to 78.6% within one year when compared to that observed at 3 years of age. In rank order of growth the best five clones were 65/27 > G3 > D121 > G48 > S7C1. Total biomass varied between 20.9 to 35.8 Mg ha–1 in different clones. Among the tree components, stemwood accounted for 52–61% of the total biomass, followed by branches (20–25%), bark (9–13%) and leaves (7–10%). No significant variation between net primary productivity and photosynthetic efficiency was found in different clones. Soybean productivity decreased as the trees aged, reaching 40.5 to 58.1% in 4-year-old trees.  相似文献   
2.
Multilineage potential of adult human mesenchymal stem cells   总被引:7,自引:0,他引:7  
Human mesenchymal stem cells are thought to be multipotent cells, which are present in adult marrow, that can replicate as undifferentiated cells and that have the potential to differentiate to lineages of mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma. Cells that have the characteristics of human mesenchymal stem cells were isolated from marrow aspirates of volunteer donors. These cells displayed a stable phenotype and remained as a monolayer in vitro. These adult stem cells could be induced to differentiate exclusively into the adipocytic, chondrocytic, or osteocytic lineages. Individual stem cells were identified that, when expanded to colonies, retained their multilineage potential.  相似文献   
3.
The effect of Cd on biochemical changes in the free floating duck weed (Spirodela polyrrhiza L. SP20) was studied. Cadmium enhanced senescence; enzymes like peroxidase, protease and phosphatases, which are known as a marker of senescence, were increased after Cd treatment. Nitrate reductase activity was also increased. With increasing Cd levels, Ca, Mg, and Zn concentrations in the plant were decreased while the Fe concentration was increased.  相似文献   
4.
Association mapping was undertaken in common wheat to identify markers associated with pre-harvest sprouting tolerance (PHST). For this purpose, a population of 242 wheat genotypes and 250 SSR markers were used. The population used consisted of diverse germplasm, which carried sufficient phenotypic variation for PHS for conducting association mapping. The population was found to be structured and stratified into 15 sub-populations; the tolerant and moderately tolerant wheat genotypes were distributed in all the sub-populations. This feature of the population along with other information on population structure was used in association mapping using both the available models, the general linear model (GLM) and the mixed linear model (MLM); hopefully, this minimized the rate of false positives. As many as 30 markers were found to be associated with PHST, 26 markers with GLM and 17 markers with MLM; 13 markers were detected using both the approaches. Only eight SSR markers associated with QTL for PHST were such, which were located within the marker intervals that were earlier reported to carry QTLs for PHST. The remaining 22 markers that were found to be associated with PHST could not be associated with any of the genomic regions known to carry QTLs for PHST, which are known to occur on all the 42 chromosome arms of wheat genome.  相似文献   
5.
Shoot tips obtained from in vitro grown plantlets of guava (Psidium guajava L.) were encapsulated in calcium alginate beads for short-term storage and germplasm exchange. A gelling matrix of 3% sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Maximum percent response for conversion of encapsulated shoot tips into plantlets was obtained on growth regulator free full strength liquid MS medium. The regrowth ability of encapsulated shoot tips was affected by medium strength and sucrose concentrations in the medium. Encapsulated shoot tips could be stored at low temperature (4 °C) up to 30 days with a survival frequency of 25%. After 60 days of storage under minimal growth conditions (sucrose lacking medium), about 75% encapsulated shoot tips were converted into plantlets when subcultured on 3% sucrose containing medium. Plantlets regenerated from encapsulated shoot tips were acclimatized successfully.  相似文献   
6.
Interacting sets of actin assembly factors work together in cells, but the underlying mechanisms have remained obscure. We used triple-color single-molecule fluorescence microscopy to image the tumor suppressor adenomatous polyposis coli (APC) and the formin mDia1 during filament assembly. Complexes consisting of APC, mDia1, and actin monomers initiated actin filament formation, overcoming inhibition by capping protein and profilin. Upon filament polymerization, the complexes separated, with mDia1 moving processively on growing barbed ends while APC remained at the site of nucleation. Thus, the two assembly factors directly interact to initiate filament assembly and then separate but retain independent associations with either end of the growing filament.  相似文献   
7.
Atrial natriuretic factor (ANF) is a peptide hormone that is released from atria and regulates a number of physiological processes, including steroidogenesis in adrenal cortex and testes. The parallel stimulation of membrane guanylate cyclase and corticosterone production in isolated fasciculata cells of rat adrenal cortex has supported the hypothesis of a mediatory role for cyclic guanosine monophosphate (cyclic GMP) in signal transduction. A novel particulate guanylate cyclase tightly coupled with ANF receptor was purified approximately 273,000-fold by two-step affinity chromatography. The enzyme had a molecular size of 180 kilodaltons and was acidic in nature with a pI of 4.7. Its specific activity was 1800 nanomoles of cyclic GMP formed per minute per milligram of protein. The purified enzyme bound ANF with a specific binding activity of 4.01 nanomoles per milligram of protein, a value that is close to the theoretical binding activity of 5.55 nanomoles per milligram of protein for 1 mole of the ligand binding 1 mole of the receptor protein. These results indicate that the guanylate cyclase-coupled ANF receptor exists in a 180-kilodalton protein of rat adrenocortical carcinoma and represent a step toward the elucidation of the basic mechanism of cyclic GMP-mediated transmembrane signal transduction in response to a hormone.  相似文献   
8.
Shoot tip explants obtained from in vitro proliferated shoots were encapsulated in 3% sodium alginate and 100 mM calcium chloride for the production of synthetic seed in Solanum nigrum L., a medicinally important plant. Morphogenic responses of encapsulated shoot tips to various sowing media (full or half-strength 0.8% agar-solidified or liquid MS medium or full-strength MS medium containing BAP) were evaluated in vitro. Of the six media evaluated, maximum conversion was obtained on 0.8% agar-solidified growth regulator free full-strength MS medium. The addition of MS nutrients in alginate matrix had a pronounced effect on the length of shoots that emerged from alginate beads. Encapsulated shoot tips also converted when directly sown in sterile soil moistened with liquid MS medium. Encapsulated shoot tips could be stored at low temperature (4 °C) up to 60 days. Plantlets regenerated from encapsulated shoot tips were acclimatized successfully.  相似文献   
9.
The present investigation was carried out to decipher inheritance of resistance and to identify linked SSR markers for Phomopsis blight resistance in eggplant. An F2 population comprising 161 plants was developed from the cross of Pusa Kranti and BR-40-7. Genetic analysis was carried out using Chi square test. Artificial inoculation of fruits was carried out using pin prick method, and scoring was done as per the standard scoring scale. The F2 plants segregated into 92 susceptible (77—highly susceptible, 15—susceptible): 69 resistant (17—highly resistant, 27—resistant, 25—moderately resistant) suggesting complimentary epistasis with ratio of 9:7. To identify the putatively linked markers to resistance gene, parental polymorphic markers were subjected to bulk segregant analysis (BSA), and two markers (emk03O04 and emf11A03) could differentiate resistant and susceptible bulk and co-segregated with resistance gene. The genetic distance between the identified markers was found to be 18.12 cM using QTL IciMapping V3.2 software depicting two new QTLs on chromosome number 6. The identified QTLs have great significant importance in marker assisted breeding programme.  相似文献   
10.
The molluscicidal activity of seed and lyophilized latex powder of Carica papaya and seed powder of Areca catechu against the vector snail Lymnaea acuminata was studied. The toxicity of these plant products was time and dose dependent. The toxicity of C. papaya lyophilized latex powder (LC(50) at 96 h: 8.38 mg/l) was more pronounced than that of A. catechu seed powder (LC(50) at 96 h: 12.32 mg/l) and C. papaya seed powder (LC(50) at 96 h: 61.56 mg/l). Ethanolic extracts of C. papaya seed and A. catechu seed were more toxic than their other extracts. The ethanolic extract of A. catechu seed (LC(50) at 24h: 17.21 mg/l) was more effective than the ethanolic extract of C. papaya seed (LC(50) at 24h: 53.38 mg/l). The LC(50) of column-purified fraction of A. catechu seed at 96 h was 3.99 mg/l, whereas that of C. papaya seed was 7.06 mg/l. C. papaya and A. catechu may be used as potent molluscicides since the concentrations used to kill the snails were not toxic for the fish Colisa fasciatus which shares the same habitat with the snail L. acuminata.  相似文献   
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