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Salinity and Orobanche or Phelipanche spp. infection are important crop stress factors in agricultural areas. In this study, we investigated the effect of salt stress on Phelipanche ramosa seed germination and its attachment onto Arabidopsis thaliana roots. We also evaluated the effect of both stresses on the expression of genes regulated by abiotic and biotic stresses. According to our results, high concentration of NaCl delayed P. ramosa seed germination in the presence of a strigolactone analogue (GR24). A similar pattern was observed in the presence of A. thaliana plants. Furthermore, we found that salt‐treated A. thaliana seedlings were more sensitive to P. ramosa attachment compared with the untreated plants, indicating that there was a positive correlation between salt sensitivity and the ability of P. ramosa to infect A. thaliana plants. At the molecular level, a synergystic effect of both salt and P. ramosa stresses was observed on the cold‐regulated (COR) gene expression profile of treated A. thaliana seedlings. Our data clarify the interaction between parasitic plants and their hosts under abiotic stress conditions. 相似文献
3.
Abstract There have been several attempts to distinguish farmed Atlantic salmon by origin using trademarks. Whether there exist different regional markets for salmon, and in particular whether the UK market is separate from the market in continental Europe, is also an issue that has received attention. To address these questions, we investigate the relationship between Norwegian and Scottish salmon both in France and the UK, and between Scottish salmon in France and the UK. The analysis is carried out by investigating how the development of prices is related using co‐integration tests. 相似文献
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Spathe regreening is a primary determinant limiting the postharvest quality for most hybrids of Zantedeschia, e.g. ‘Best Gold’, wherein the spathe commences regreening approximately two days after it is fully open. To identify an effective method to postpone the regreening, several synthetic plant hormones were evaluated for their influence on changes in color during regreening of discs excised from the spathe of ‘Best Gold’. The tested synthetic plant hormones included 6-benzylaminopurine (BAP), zeatin, N1-(2-chloro-4-pyridyl)-N3-phenylurea (CPPU) and GA3 at concentrations up to 0.1 mM. A concentration of BAP at 0.5 mM resulted in phytotoxicity symptoms on discs. Subsequently, the effect of a combination of BAP and GA3 on the regreening was examined. Application of the cytokinins (in particular BAP at 0.1 mM) or GA3 alone resulted in a one to five day delay in regreening on the spathe tissue. The most effective treatment in delaying regreening was from the simultaneous application of GA3 and BAP in a ratio of 1:1 (v:v) at 0.1 mM, wherein regreening was delayed for more than ten days. This treatment was then tested on the entire inflorescence, resulting in a delay in regreening for between seven and eight days. 相似文献
6.
Effects of high pressure argon (H), ultrasound (U) and their combination treatments (UH) on physico-chemical characteristics of white mushrooms were studied during 9 d of postharvest storage at 4 °C. H treated samples exhibited the smallest weight loss and respiration rate compared to all other samples. Mass losses after 9 d of storage were 3.01%, 5.09%, 5.39% and 9.59% for H, UH, U and untreated mushrooms, respectively. Furthermore, U treated samples showed lower polyphenol oxidase activity (PPO, E.C. 1.14.18.1) during storage while UH treated samples showed a slight increase in antioxidant capacity during storage and also experienced reduced mass loss and respiration rate. In addition, treated samples were effective in retaining mushrooms colour changes compared to control. Physico-chemical properties of differently treated mushrooms (UH, H and U) stored at 4 °C were significantly different (p < 0.05) from control. 相似文献
7.
P. Colangeli S. Iannetti L. Ruocco L. Forlizzi D. Cioci P. Calistri 《Zoonoses and public health》2013,60(2):182-188
In the framework of the international obligations subscribed by the Italian government, the Italian Ministry of Health should provide the European Union (EU) (European Commission, European Food Safety Authority – EFSA) with a set of data and information related to the report and the spread of zoonoses and to the activities put in place for monitoring and control of zoonoses. In 2008, the Italian Ministry of Health commissioned the Istituto G. Caporale (ICT) to implement an information system able to provide information and data on the monitoring and control of zoonoses in the national territory, in accordance with the national and community legislation. The system is part of the e‐Government process that involves all public administrations of the EU and refers to the use of information and communication technologies for the digital processing of documents in order to obtain simplification and interoperability of administrative procedures through the Internet, as defined in the strategic lines published by the National Centre for Information Systems in Public Administration (DigitPA) in 2009–2011. 相似文献
8.
Laboratory tests of Metarhizium anisopliae var acridum Driver & Milner, at a dose of 1.3 x 10(6) conidia ml-1, had no adverse effects on nymphs of mayfly, Ulmerophlebia sp or 8-week-old fry of the rainbow fish, Melanotaenia duboulayi Castelnau. This dose was toxic to the cladoceran, Ceriodaphnia dubia Richard, causing 100% mortality in 48 h. When this test was repeated at doses of up to 6.7 x 10(3) conidia ml-1, there was only 5% mortality after 192 h. Spraying of artificial water sources with a very high dose of the fungus as an aqueous spray resulted in 80-130 conidia ml-1 at 15 cm depth in the first 24 h after spraying. The conidia rapidly settled out and were absent from the top 15 cm layer of water after about 50 h. A similar experiment using the oil formulation as used in field control resulted in a 2- to 20-fold lower level of conidia in the water. Finally, sampling actual water sources in spray areas revealed a very low level of contamination of the water, with a maximum mean level of 29 conidia ml-1 in the first 24 h after treatment. Thus the level of conidia likely to enter water during control campaigns is a small fraction of that required to kill cladocerans, the only sensitive non-target organism tested. It is concluded that the biopesticide is very unlikely to pose any hazard to aquatic organisms. 相似文献
9.
van Galen G Cassart D Sandersen C Delguste C Nollet H Amory H Ducatelle R 《Equine veterinary journal》2008,40(2):185-188
Polyneuritis equi (PNE) is a rare neurological disease in the horse. Because of the suspicion in PNE of a T-lymphocyte mediated immune response against the myelin, the objective of this study was to determine the composition of the inflammatory infiltrate in the involved nerves of 3 horses with PNE, studied retrospectively. T-lymphocytes were demonstrated in the lesions, which suggests a T-lymphocyte mediated immune response against myelin. In addition, the presence of B-lymphocytes indicated a local production of antibodies. More research, involving a prospective study, is needed to determine whether the T-lymphocytes are cytotoxic or T-helper lymphocytes. 相似文献
10.
Pillonel C 《Pest management science》2005,61(11):1069-1076
The effects of diverse phenylaminopyrimidines (PAP), namely PAP-pyridines (type A), PAP-pyrazoles (type B) and PAP-thiazoles (type C), on Neurospora crassa Shear & Dodge has been investigated. The results revealed that type A strongly inhibit the in vitro growth of N crassa, whereas types B and C are much less active. A significant correlation was observed between the Neurospora growth inhibition and the intrinsic activity of type A compounds on the cyclin-dependent protein kinase p34(CDC2) of starfish, suggesting that the target of phenylaminopyrimidines in fungi is a cyclin-dependent protein kinase (CDK). The phenylaminopyrimidine-binding CDKs Phoss (major band) and CDC2 (minor band) involved in phosphorus uptake, glycogen synthesis and the cell cycle were identified from N crassa by affinity chromatography on phenylaminopyrimidine-sepharose. Comparative experiments with different protein kinases revealed the importance of the side chain of phenylaminopyrimidines for their target selectivity. A type B compound was found to selectively inhibit the MAP-kinase OS-2 involved in the osmoregulatory pathway of Neurospora. 相似文献