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排序方式: 共有282条查询结果,搜索用时 31 毫秒
271.
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Juan Majada Celia Martínez-Alonso Isabel Feito Angelo Kidelman Ismael Aranda Ricardo Alía 《New Forests》2011,41(3):399-412
Pinus pinaster Ait. is one of the main forest tree species planted in Spain, Portugal and France. Due to its high economic relevance, there
is considerable interest in developing techniques for vegetative breeding aimed at mass propagation. In this study we present
a mini-propagation protocol in order to define an efficient method to propagate families or clones of P. pinaster. We carried out three experiments using mini-cuttings of 3–5 cm in length with the aim of evaluating the effects of temperature
(4°C vs. 25°C), plant growth regulator (IBA) and shoot age on rooting ability. Percentage of rooted cuttings and morphological
root variables were recorded. The percentage of rooted cuttings per treatment ranged from 68 to 97%. Treatment with IBA significantly
influenced the rooting process at 25°C but not at 4°C. The number of apexes, length, area and volume of roots were all positively
affected by temperature treatment. Shoot age also had a positive effect on rooting capacity of cuttings, with the cuttings
from the youngest shoots (70 days after pruning) having higher rooting percentages, ranging from 84.7 to 98.3%. The use of
juvenile material, good environmental conditions and IBA all benefited the rooting of clonal material, resulting in high rooting
capacity. This study presents an innovative propagation protocol for P. pinaster that can be used as a tool in breeding programs. 相似文献
274.
Marmiroli M Pietrini F Maestri E Zacchini M Marmiroli N Massacci A 《Tree physiology》2011,31(12):1319-1334
Worldwide, there are many large areas moderately contaminated with heavy metals and/or organics that have not been remediated due to the high cost and technical drawbacks of currently available technologies. Methods with a good potential for coping with these limitations are emerging from phytoremediation techniques, using, for example, specific amendments and/or plants selected from various candidates proven in several investigations to be reasonably efficient in extracting heavy metals from soil or water, or in co-metabolizing organics with bacteria flourishing or inoculated in their rhizospheres. Populus and Salix spp., two genera belonging to the Salicaceae family, include genotypes that can be considered among the candidates for this phytoremediation approach. This review shows the recent improvements in analytical tools based on the identification of useful genetic diversity associated with classical growth, physiological and biochemical traits, and the importance of plant genotype selection for enhancing phytoremediation efficiency. Particularly interesting are studies on the application of the phytoremediation of heavy metals and of chlorinated organics, in which microorganisms selected for their degradation capabilities were bioaugmented in the rhizosphere of Salicaceae planted at a high density for biomass and bioenergy production. 相似文献
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276.
Ventura M Antonacci F Cardone MF Stanyon R D'Addabbo P Cellamare A Sprague LJ Eichler EE Archidiacono N Rocchi M 《Science (New York, N.Y.)》2007,316(5822):243-246
A systematic fluorescence in situ hybridization comparison of macaque and human synteny organization disclosed five additional macaque evolutionary new centromeres (ENCs) for a total of nine ENCs. To understand the dynamics of ENC formation and progression, we compared the ENC of macaque chromosome 4 with the human orthologous region, at 6q24.3, that conserves the ancestral genomic organization. A 250-kilobase segment was extensively duplicated around the macaque centromere. These duplications were strictly intrachromosomal. Our results suggest that novel centromeres may trigger only local duplication activity and that the absence of genes in the seeding region may have been important in ENC maintenance and progression. 相似文献
277.
Helena Gaspar Adele Cutignano Laura Grauso Nuno Neng Vasco Cachatra Angelo Fontana Joana Xavier Marta Cerejo Helena Vieira Susana Santos 《Marine drugs》2016,14(10)
Among marine organisms, sponges are the richest sources of pharmacologically-active compounds. Stemming from a previous lead discovery program that gathered a comprehensive library of organic extracts of marine sponges from the off-shore region of Portugal, crude extracts of Erylus cf. deficiens collected in the Gorringe Bank (Atlantic Ocean) were tested in the innovative high throughput screening (HTS) assay for inhibitors of indoleamine 2,3-dioxygenase (IDO) and showed activity. Bioassay guided fractionation of the dichloromethane extract led to the isolation of four new glycolipids, named erylusamide A–D. The structures of the isolated compounds were established by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and chemical derivatization. The metabolites shared a pentasaccharide moiety constituted by unusual highly acetylated d-glucose moieties as well as d-xylose and d-galactose. The aglycones were unprecedented long chain dihydroxyketo amides. Erylusamides A, B and D differ in the length of the hydrocarbon chain, while erylusamide C is a structural isomer of erylusamide B. 相似文献
278.
279.
Gabriella Sonnante Anna Vittoria Carluccio Angelo De Paolis Domenico Pignone 《Genetic Resources and Crop Evolution》2008,55(7):1029-1046
A set of 24 microsatellite markers was identified in the artichoke genome, using various approaches. A genomic library allowed
the development of 14 SSR markers, whereas the other 10 were obtained from gene intron/UTR regions or from other species.
Allelic variation was scored in C. cardunculus (artichoke, cultivated cardoon, and wild cardoon) samples, and in other wild Cynara allies. For the 23 polymorphic loci, a total of 165 alleles were scored, 135 of which in the artichoke primary genepool,
and the remaining ones in the other Cynara species. Some allele combinations were able to identify artichoke varietal types, and some alleles were unique to specific
groups. This makes these markers potentially useful in product traceability and in contributing to the saturation of genetic
maps. The percentage of shared alleles between C. cardunculus taxonomic groups, and Nei’s genetic distances indicated that wild cardoons from the Eastern Mediterranean were more closely
related to artichoke and less to cultivated cardoon in comparison to wild cardoons from the Western Mediterranean, and the
genetic distance between the two wild cardoon genepools was rather high. The UPGMA dendrogram based on Nei’s genetic distances
revealed that artichokes formed a fairly defined cluster, whereas Eastern wild cardoons occupied another branch, and Western
wild cardoons were clustered together with cultivated cardoons. The transferability of microsatellite markers to other Cynara wild species was quite good. Sequencing alleles at three loci showed that, apart from microsatellite length variation, point
mutations and insertion/deletions were quite abundant especially when comparing C. cardunculus to the other Cynara species. In the sequenced regions, some SNPs were identified which distinguished artichoke on one side, and cultivated and
wild cardoon on the other, while other SNPs were apportioned according to the geographic distribution of Cynara wild species. 相似文献
280.
Lisboa AC Mello IC Nunes RS Dos Santos MA Antoniolli AR Marçal RM Cavalcanti SC 《Fitoterapia》2006,77(6):439-442
Oral administration of hexanes, chloroform, and ethyl acetate extracts of the leaves of Hyptis pectinata significantly reduced the number of writhing induced by acetic acid and increased the response to thermal stimuli in hot-plate test. Such effect was completely reversed by the opioid antagonist naloxone. 相似文献