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991.
Josefine Nymark Hegelund Uffe Bjerre Lauridsen Sabá Victoria Wallström Renate Müller Henrik Lütken 《Euphytica》2017,213(2):51
Compact growth is an important quality criterion in horticulture. Many Campanula species and cultivars exhibit elongated growth which is suppressed by chemical retardation and cultural practice during production to accommodate to the consumer’s desire. The production of compact plants via transformation with wild type Agrobacterium rhizogenes is an approach with great potential to produce plants that are non-GMO. Efficient transformation and regeneration procedures vary widely among both plant genera and species. Here we present a transformation protocol for Campanula. Hairy roots were produced on 26–90% of the petioles that were used for transformation of C. portenschlagiana (Cp), a C. takesimana × C. punctata hybrid (Chybr) and C. glomerata (Cg). Isolated hairy roots grew autonomously and vigorously without added hormones. The Cg hairy roots produced chlorophyll and generated plantlets in response to treatments with cytokinin (42 µM 2iP) and auxin (0.67 µM NAA). In contrast, regeneration attempts of transformed Cp and Chybr roots lead neither to the production of chlorophyll nor to the regeneration of shoots. Agropine A. rhizogenes strains integrate split T-DNA in TL- and TR-DNA fragments into the plant genome. In this study, regenerated plants of Cg did not contain TR-DNA, indicating that a selective pressure against this T-DNA fragment may exist in Campanula. 相似文献
992.
Issei Kobayashi Masako Yamada Yuhko Kobayashi 《Journal of General Plant Pathology》2007,73(6):399-404
To determine whether Ca2+ promotes powdery mildew penetration, Ca2+-treated barley coleoptiles were inoculated with conidia of pathogenic and nonpathogenic fungi. Penetration efficiency of
the pathogenic powdery mildew Blumeria graminis was enhanced by Ca2+ treatment, but that of the necrotrophic pathogen Helminthosporium sp. remained unaffected. Similarly, when actin-dependent penetration resistance is suppressed with cytochalasin A, Ca2+ treatment specifically enhanced penetration of the nonpathogenic powdery mildew Erysiphe pisi but not that of other nonpathogens. Calmodulin inhibitors suppressed the promotive effect of Ca2+ on B. graminis penetration. These results suggest that barley powdery mildew specifically requires Ca2+ and calmodulin for penetration. 相似文献
993.
Fangjing Li Gaoqing Yuan Ting Liao Qiqin Li Wei Lin 《Journal of General Plant Pathology》2017,83(4):264-267
In 2014 and 2015, an unknown leaf spot disease was found on tobacco in Guangxi, China. The fungus isolated from these spots was identified as Fusarium proliferatum based on morphological characteristics and sequence analysis of translation elongation factor 1 alpha (tef1α). This fungus also reproduced leaf spot symptoms after inoculation and was reisolated from the symptomatic lesions. This is the first report of a new leaf spot caused by Fusarium proliferatum on tobacco. 相似文献
994.
Kifah Jumaah Odhaib Kazeem Dauda Adeyemi Muideen Adewale Ahmed Muhammad Faseleh Jahromi Shokri Jusoh Anjas Asmara Samsudin Abdul Razak Alimon Halimatun Yaakub Awis Qurni Sazili 《Tropical animal health and production》2018,50(5):1011-1023
The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68?±?0.6 kg, 4–5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P?< 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P?< 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P?< 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P?< 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P?<?0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P?< 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P?< 0.05) neutrophils, basophils and serum urea and greater (P?<?0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition. 相似文献
995.
Nathaly Enciso Luciana L. K. Ostronoff Guillermo Mejías Leticia G. León María Luisa Fermín Elena Merino Cristina Fragio Luis Avedillo Concepción Tejero 《Veterinary research communications》2018,42(1):29-38
Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration. 相似文献
996.
As the levels of radioactivity in seafood have fallen back into the safe range, Fukushima fisheries are considering reopening. However, even if seafood from the Fukushima area were sufficiently safe to distribute to seafood markets, its value may be undermined because of the damage done to its reputation by the Fukushima disaster. We quantified consumers’ preferences for seafood from Fukushima and adjacent prefectures to examine the extent of the reputational damage to Fukushima seafood. We conducted a choice experiment to measure consumers’ willingness to pay for seafood from the Fukushima area. We also measured the impact of displaying ecolabels [Marine Stewardship Council (MSC) and Marine Eco-label Japan (MEL)] on Fukushima products. The results indicated that Fukushima products are considerably discounted compared with products displayed as domestic; even products from adjacent prefectures are substantially discounted. By contrast, consumers positively evaluated locally labeled products. We also found that demersal fish are discounted more than pelagic fish that inhabit the ocean surface off the shore of Fukushima. 相似文献
997.
Yigang Hu Zengru Wang Qi Wang Shiping Wang Zhishan Zhang Zhenhua Zhang Yang Zhao 《Journal of Soils and Sediments》2017,17(2):326-339
Purpose
Changes in bioactive soil C pools and their temperature sensitivities will dominate the fate of soil organic C in a warmer future, which is not well understood in highland ecosystems. This study was conducted in order to evaluate climate change, especially cooling effects, on soil labile organic C (LOC) pools in a Tibetan alpine meadow.Materials and methods
A short-term reciprocal translocation experiment was implemented to stimulate climate warming (downward translocation) and cooling (upward translocation) using an elevation gradient on the Tibetan Plateau. Variations in soil microbial biomass C (MBC), dissolved organic C (DOC) and LOC were analyzed.Results and discussion
Over the range of soil temperature from 0.02 to 5.5 °C, warming averagely increased soil MBC, DOC and LOC by 15.3, 17.0 and 3.7 % while cooling decreased them by 11.0, 11.9 and 3.2 %, respectively. Moreover, warming generally increased the proportion of DOC in LOC but cooling had an opposite effect, while the response of the MBC proportion to DOC and LOC varied depending on vegetation type. Soil MBC, DOC and LOC pools were positively related to soil temperature and showed a hump-shaped relationship with soil moisture with a threshold of about 30–35 %. Although soil DOC was more sensitive to warming (5.1 % °C?1) than to cooling (3.0 % °C?1), soil LOC showed a symmetrical response due to regulation by soil moisture.Conclusions
Our results indicated that climate change would not only change the size of soil LOC pools but also their quality. Therefore, cooling effects and regulation of soil moisture should be considered to evaluate the fate of soil organic C in Tibetan alpine meadows in a warmer future.998.
Three slow-growing legume trees used for desert reforestation and urban gardening in the Sonoran Desert of Northwestern Mexico
and the Southwestern USA were evaluated whether their growth can be promoted by inoculation with plant growth-promoting bacteria
(Azospirillum brasilense and Bacillus pumilus), unidentified arbuscular mycorrhizal (AM) fungi (mainly Glomus sp.), and supplementation with common compost under regular screenhouse cultivation common to these trees in nurseries. Mesquite
amargo (Prosopis articulata) and yellow palo verde (Parkinsonia microphylla) had different positive responses to several of the parameters tested while blue palo verde (Parkinsonia florida) did not respond. Survival of all tree species was over 80% and survival of mesquite was almost 100% after 10 months of cultivation.
Inoculation with growth-promoting microorganisms induced significant effects on the leaf gas exchange of these trees, measured
as transpiration and diffusive resistance, when these trees were cultivated without water restrictions. 相似文献
999.
Hyper-spectral remote sensing to monitor vegetation stress 总被引:1,自引:0,他引:1
Hong-Yan Ren Da-Fang Zhuang Jian-Jun Pan Xue-Zheng Shi Hong-Jie Wang 《Journal of Soils and Sediments》2008,8(5):323-326
Background, aim, and scope Vegetation stress diagnoses based on plant sampling and physiochemical analysis using traditional methods are commonly time-consuming,
destructive and expensive. The measurement of field spectral reflectance is one basis of airborne or spaceborne remote sensing
monitoring.
Materials and methods In this study, paddy plants were grown in the barrels evenly filled with 10.0 kg soil that was mixed respectively with 0,
2.5 × 207.2 and 5.0 × 207.2 mg Pb per 1,000 g soil. Rice canopy spectra were gathered by mobile hyper-spectral radiometer
(ASD FieldSpec Pro FR, USA). Meanwhile, canopy leaves in the field-of-view (FOV) of spectroradiometer were collected and then
prepared in the laboratory, (1) for chlorophyll measurement by Model 721 spectrophotometer, and (2) for Pb determination by
atomic absorption spectrophotometer (SpectraAA-220FS).
Results and discussion Canopy spectral reflectance in the region of visible-to-near-infrared light (VNIR) increased, because ascended Pb concentration
caused the decrease of canopy chlorophyll content. In the agro-ecosystem, however, heavy metal contamination is presented
typically as mixture and their interactions strongly affect actually occurring effects. Normalized spectral absorption depth
(D
n), and shifting distance (DS) of red edge position (REPs) revealed the differences in Pb concentration for canopy leaves,
especially at the early tillering stage. Due to insufficient biomass of rice plants, the 30th day was not reliable enough
for the selection of crucial growth stages. Some special sensitive bands might be omitted at the same time because of limited
sample sets.
Conclusions Our initial experiments are still too few in the amounts of both metals and plants neither to build accurate prediction models
nor to discuss the transformation from ground to air/spaceborne remote sensing. However, we are pleased to communicate that
ground remote sensing measurements would provide reliable information for the estimation of Pb concentration in rice plants
at the early tillering stage when proper features (such as DS and D
n) of reflectance spectra are applied.
Recommendations and perspectives Hyper-spectral remote sensing is a potential and promising technology for monitoring environmental stresses on agricultural
vegetation. Further ground remote sensing experiments are necessary to evaluate the possibility of hyper-spectral reflectance
spectroscopy in monitoring different kinds of metals’ stress on various plants. 相似文献
1000.
In this work, dopamine hydrochloride, an environmental friendly compound, was applied on polyester fabric through conventional simple impregnation method in alkaline solution (pH=8.5) at room temperature. In situ spontaneous oxidative polymerization of dopamine form polydopamine (PDA) along with aminolysis of polyester fabric surface. Also, a range of colored polyester fabric were successfully achieved by formation of polydopamine adhesive coating layer at different concentration of dopamine hydrochloride (0.001-4 g/l). Fourier transform infrared spectroscopy and field emission scanning electron microscopy showed deposition of polydopmaine on the polyester fabric surface. The modified colored polyester fabric showed reasonable durability against washing, rubbing and light. The treated polyester fabric with 2 g/l dopamine hydrochloride as optimum concentration indicated not only lower spreading time for water droplet and electrical resistance with higher tensile strength but also very good bactericidal activity against Staphylococcus aureus and Escherichia coli. 相似文献