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141.
The characterization of plant genetic resources is the first step towards improving their use. The Spanish Plant Genetic Resources
Centre, which belongs to the National Institute for Agricultural and Food Technology Research (CRF-INIA), conserves accessions
of wild underground vetches collected in Spain. In the present work, 26 underground vetch accessions were characterized in
terms of their seed storage proteins (separated by SDS-PAGE) as a means of assessing the genetic variation of these plants
and their agronomic value. Vicia sativa cv. Vereda was used as control. A total of 54 bands were detected, of which 49 were polymorphic. Fifty eight different electrophoretic
patterns were observed in total. Protein bands were scored in terms of their presence (1) or absence (0) for all the seeds
studied, and two matrices constructed, one with all the bands present in each accession, the other with the different patterns
for each accession. Dendrograms based on the Jaccard similarity index and the UPGMA clustering method were produced from these
matrices, and the degree of genetic variation between and within accessions was calculated. The groups obtained were compared
with the chromosome number for each accession. The results reflect the great diversity of underground vetch seed storage proteins.
The aerial and underground seeds of 16 accessions were then analysed separately. In some cases, the aerial and underground
flowers of the same plant produced different proteins. 相似文献
142.
Flowering dogwood (Cornus florida L.) is an ornamental tree valued for its showy white, pink, or red spring bract display and red fall color. A “pseudo” F2 flowering dogwood population was recently developed from a honeybee mediated cross of ‘Cherokee Brave’ × ‘Appalachian Spring’.
The foliage color of 94 “pseudo” F2 plants segregated into green- and red- leaved phenotypes and was visually rated for color on five spring dates over 3 years
(2007–2009). Chi-square analyses of observed segregation of phenotypes indicated that a complementary gene interaction form
of epistasis controls foliage color with a 9:7 two gene ratio. We propose the symbols rl
1
and rl
2
for the genes controlling this trait. 相似文献
143.
Neetu Shahi László Ardó Gyöngyvér Fazekas Elen Gócza Shivendra Kumar Norbert Rèvèsz Zsuzsanna Jakabné Sándor Zsuzsanna Molnár Galina Jeney Zsigmond Jeney 《Aquaculture International》2018,26(3):727-741
To evaluate the effect of thermal and microbial stress on the immune response of common carp (Cyprinus carpio L.), relative mRNA expression level of pro-inflammatory cytokines [tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β] and other genes related to immune or stress response [inducible nitric oxide synthase (iNOS), heat shock protein 70 (Hsp70), superoxide dismutase one (SOD1), and glucocorticoid receptor (GR)] was measured by quantitative PCR (qPCR). In addition, total protein and total immunoglobulin level in blood plasma of experimental common carp was also assayed. All the above parameters were estimated 24 h post-challenge with Gram-negative bacterium, Aeromonas hydrophila. Common carp (54.89?±?6.90 g) were initially exposed to 20 °C (control group) and 30 °C (thermal stress group) water temperature for 30 days, followed by experimental challenge with 2.29?×?108 colony forming unit/mL (CFU/mL; LD50 dose) of A. hydrophila. Exposure of fish to thermal stress and subsequently challenge with A. hydrophila significantly (P?<?0.05) increases the IL-1β mRNA expression in head kidney and spleen of common carp by ~?39.94 and ~?4.11-fold, respectively. However, TNF-α mRNA expression in spleen decreased ~?5.63-fold in control fish challenged with A. hydrophila. Thermal stress and challenge with bacterium suppresses the iNOS and GR mRNA expression in spleen of common carp. Moreover, significant (P?<?0.05) increase in total protein content of blood plasma (~?43 mg/g) was evident in fish exposed to thermal stress and challenged with A. hydrophila. In conclusion, our study highlights the importance of elevated temperature stress and microbial infection in differential regulation of expression of several immunogenes in common carp. 相似文献
144.
Abstract: Heterosigma akashiwo virus (HaV) is a large icosahedral virus (∼0.2 μm) harboring a double-stranded DNA (dsDNA) genome (∼294 kbp). The virus is the only member of the genus Raphidovirus in the family Phycodnaviridae. Since its first discovery, a number of ecologic, physiologic and genetic studies about HaV have been conducted; especially, the relationship between H. akashiwo and HaV in nature was studied and viral infection is now regarded as a significant factor influencing the dynamics and termination of H. akashiwo blooms. HaV infection has considerable impacts on H. akashiwo populations in both aspects of fluctuation in biomass (quantity) and changes in clonal composition (quality). Partial sequencing of the HaV genome revealed that a number of genes showed considerable similarity to those of other protist-infecting viruses; still, the phylogenetic position of HaV suggested a number of enigmas in host–virus coevolution. Here are summarized the ecology, physiology and genetics of HaV especially from the viewpoint of the host–virus relationship. 相似文献
145.
Porcu OM Rodriguez-Amaya DB 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):195-199
The indigenous pitanga (Eugenia uniflora L.) is now marketed and commercially processed in Brazil. In the present work, the carotenoids of the pitanga fruit from two states and at two stages of ripening, as well as of processed pitanga products (frozen pulp and juice, the brands being designated as A, B and C) commercialized in Campinas, São Paulo, were determined by HPLC. As compared to ripe pitanga from Medianeira, Paraná, those from Campinas had significantly higher (all-E)-lycopene (14.0 vs. 71.1 μg/g), (13Z)-lycopene (1.1 vs. 5.0 μg/g) and (all-E)-γ-carotene (1.6 vs. 3.8 μg/g) levels. Significant increases in most of the carotenoids occurred from the partially ripe to the ripe fruits, with (all-E)-lycopene doubling its concentration in fruits from both states. Pitanga was found to be one of the richest fruit sources of carotenoids, particularly lycopene, but the processed products had much lower lycopene content. The mean (all-E)-lycopene concentration was 16.6 μg/g for frozen pulp brand A, 23.0 μg/g for bottled juice brand B and 25.6 μg/g for bottled juice brand C. Optimization of processing is therefore needed to guarantee better retention of this important carotenoid. 相似文献
146.
A series of shape memory polyurethane (PU) copolymers synthesized from 1,4-phenyldiisocyanate (PDI), poly(tetramethyleneglycol)
(PTMG), 1,4-butanediol (BD) as a chain extender, and glycerol as a cross-linking agent were tested for the mechanical properties
and the shape memory effect at the temperature 20 °C above melting temperature (T
m), and were compared with other PUs synthesized from 4,4′-methylene-bis-phenyldiisocyanate (MDI), PTMG, and BD. Mechanical
properties and shape memory effect were improved substantially by adopting both PDI and glycerol. Interestingly, enthalpy
of melting and T
m were not affected by the glycerol content. Vibration and shock absorption ability was investigated by measuring both loss
tan δ and storage modulus with dynamic mechanical analyzer (DMA). 相似文献
147.
Previously, we have reported a method for producing photochromic wool fabric by applying a thin layer of hybrid silica-photochromic
dye onto the wool surface. While the photochromic coating showed a very fast optical response and had little influence on
the fabric handle, its durability was poor. In this study, the durability of the photochromic coating layer was improved by
introducing epoxy groups into the silica matrix via co-hydrolysis and co-condensation of an alkyl trialkoxysilane compound
(ATAS) and 3-glycidoxypropyltrimethoxysilane (GPTMS). The presence of epoxy groups in the silica enhanced both washing and
abrasion durability or fastness. In addition, the optical response speed was slightly increased as well. Effects of the type
of alkyl silane and the GPTMS/alkyl silane ratio on the coating durability, fabric handle and optical response were examined. 相似文献
148.
Innovations in precision agriculture (PA) have created opportunities to achieve a greater understanding of within-field variability. However, PA adoption has been hindered by uncertainty about field-specific performance and return on investment. Uncertainty could be better addressed by using innovative analyses that provide insights into variability among fields and across a region. The objectives of this research were to: (1) generate a within-field soil clay-content variability index (VIc), (2) create a regional-scale growing-season precipitation variability index (VIp), and (3) integrate the soil and weather indices with the USDA NRCS soil erosion vulnerability index (SVI) to produce a final index that incorporated both variability and vulnerability (VVI). The interpretation of the outcomes represented by each objective supports unique decisions that land managers may consider for reducing uncertainty about implementing PA. All indices were derived using publically available information for Missouri, USA. The VIc was the ratio between the maximum and minimum clay content within fields. The VIp was calculated as the standard deviation of the total growing-season precipitation from 2006 to 2015. Significant clustering of VIc and VIp were observed along the Missouri River corridor, northeast and northwest Missouri. Fields with high VVI were mostly in the claypan soil region of northeast Missouri, and along a portion of the Missouri River dominated by loess soils on steep slopes. Southeast Missouri displayed the greatest diversity in soil and weather variability, but had low vulnerability. This research could be used as a decision-support tool to aid producers and PA service and product providers in determining where PA opportunities exist. 相似文献
149.
M. Meron J. Tsipris Valerie Orlov V. Alchanatis Yafit Cohen 《Precision Agriculture》2010,11(2):148-162
Variable-rate irrigation by machines or solid set systems has become technically feasible, however mapping crop water status
is necessary to match irrigation quantities to site-specific crop water demands. Remote thermal sensing can provide such maps
in sufficient detail and in a timely way. In a set of aerial and ground scans at the Hula Valley, Israel, digital crop water
stress maps were generated using geo-referenced high-resolution thermal imagery and artificial reference surfaces. Canopy-related
pixels were separated from those of the soil by upper and lower thresholds related to air temperature, and canopy temperatures
were calculated from the coldest 33% of the pixel histogram. Artificial surfaces that had been wetted provided reference temperatures
for the crop water stress index (CWSI) normalized to ambient conditions. Leaf water potentials of cotton were related linearly
to CWSI values with R
2 = 0.816. Maps of crop stress level generated from aerial scans of cotton, process tomatoes and peanut fields corresponded
well with both ground-based observations by the farm operators and irrigation history. Numeric quantification of stress levels
was provided to support decisions to divide fields into sections for spatially variable irrigation scheduling. 相似文献
150.
Muzafar A. Kanjwal Nasser A. M. Barakat Faheem A. Sheikh Woo-il Baek Myung Seob Khil Hak Yong Kim 《Fibers and Polymers》2010,11(5):700-709
As titanium oxide is a well-known photocatalyst, we investigated the effects of silver content and nanostructural morphology
on the photocatalytic degradation of two dyes, methylene blue and rhodamine B. Two nano-formulations were utilized, including
nanofibers and nanoparticles. Silver-grafted titanium oxide nanofibers were synthesized using the electrospinning of silver
nitrate/titanium isopropoxide/poly(vinyl acetate) sol-gel. The nanoparticulate form was obtained by calcination of a ground
powder prepared from the same electrospun sol-gel. The results affirmed the advantage of the silver-grafted titanium oxide
nanostructures over the silver-free ones. Increasing the silver content in the nanofibers led to increases in their surface
area, which is an important parameter in heterogeneous catalytic chemical reactions. Therefore, the results strongly suggest
the use of silver-grafted titanium oxide in a nanofibrous form. These results further support utilizing Agloaded titanium
oxide nanofibers as a photocatalyst. 相似文献