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The influence of the electrical conductivity (EC) of the substrate solution during the night, i.e., moderately high EC (“HEC”, 3.0 dS m–1, full solution) and low EC (“LEC”, 0.5 dS m–1, CaCl2 or Ca(NO3)2 and H3BO3), on the incidences of blossom‐end rot (BER) and fruit cracking (FC) in greenhouse tomato (Solanum lycopersicum L.) was investigated and compared with a control without additional nighttime fertigation (NTF). In three consecutive experiments conducted in Central Thailand between November 2005 and March 2007, additional NTF cycles were applied for 1 h after the regular daytime fertigation (EC 1.5/1.8 dS m–1, prior to/after the first harvest). In the first experiment (dry season 2005/06), two cultivars with either low (FMTT 260) or high (King Kong 2) susceptibility to BER and FC were used. The total amount of fruits affected by FC or BER was 4‐ and 10‐fold, respectively, higher in King Kong 2, but the relative response to NTF was similar in both cultivars. Therefore, in the following experiments only FMTT 260 was planted. In all experiments, NTF exerted significant effects on the uptake and allocation of water and mineral elements to the fruits and the proportions of fruits affected by BER and FC. The overall proportion of nonmarketable fruits was not significantly reduced, neither through LEC nor HEC because a decrease in BER by LEC and in FC by HEC was counteracted by enhanced FC in LEC and BER in HEC. It is concluded that under the tropical climate conditions of Central Thailand leading to high losses of marketable fruit yield through BER and FC, an integrated approach is required combining an optimized management of the fertigation system and particularly the selection of genotypes highly tolerant of BER and FC. 相似文献
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135.
Journal of Plant Diseases and Protection - Whiteflies are major pests on several vegetable and ornamental crops. Landing behaviour is strongly influenced by wavelength (nm) of reflected light from... 相似文献
136.
Kristina Museux Felicitas S. Boretti Barbara Willi Barbara Riond Katharina Hoelzle Ludwig E. Hoelzle Max M. Wittenbrink S��verine Tasker Nicole Wengi Claudia E. Reusch Hans Lutz Regina Hofmann-Lehmann 《Veterinary research》2009,40(5)
The natural transmission routes of the three feline haemotropic mycoplasmas – Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’, and ‘Candidatus Mycoplasma turicensis’ (CMt) – are largely unknown. Since CMt has been detected in the saliva of infected cats using PCR, we hypothesised that direct transmission via social or aggressive contact may occur. The aim of this study was to evaluate this transmission route. CMt-positive saliva and blood samples were obtained from three prednisolone-treated specific pathogen-free (SPF) cats that were infected intraperitoneally with CMt. Five SPF cats were inoculated with CMt-positive saliva or blood subcutaneously to mimic cat bites, and five cats were inoculated orally with blood or oronasally with saliva to mimic social contact. Blood samples were monitored for CMt infection using quantitative real-time PCR and for seroconversion using a novel western blot assay. Neither oronasal nor subcutaneous inoculation with CMt-positive saliva led to CMt infection in the recipient cats, as determined by PCR, independent of prior prednisolone treatment. However, when blood containing the same CMt dose was given subcutaneously, 4 of the 5 cats became PCR-positive, while none of the 5 cats inoculated orally with up to 500 μL of CMt-positive blood became PCR-positive. Subsequently, the latter cats were successfully subcutaneously infected with blood. All 13 CMt-exposed cats seroconverted. In conclusion, CMt transmission by social contact seems less likely than transmission by aggressive interaction. The latter transmission may occur if the recipient cat is exposed to blood from an infected cat. 相似文献
137.
Habacher G Pittler MH Ernst E 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(3):480-488
Acupuncture is a popular complementary treatment option in human medicine. Increasingly, owners also seek acupuncture for their animals. The aim of the systematic review reported here was to summarize and assess the clinical evidence for or against the effectiveness of acupuncture in veterinary medicine. Systematic searches were conducted on Medline, Embase, Amed, Cinahl, Japana Centra Revuo Medicina and Chikusan Bunken Kensaku. Hand-searches included conference proceedings, bibliographies, and contact with experts and veterinary acupuncture associations. There were no restrictions regarding the language of publication. All controlled clinical trials testing acupuncture in any condition of domestic animals were included. Studies using laboratory animals were excluded. Titles and abstracts of identified articles were read, and hard copies were obtained. Inclusion and exclusion of studies, data extraction, and validation were performed independently by two reviewers. Methodologic quality was evaluated by means of the Jadad score. Fourteen randomized controlled trials and 17 nonrandomized controlled trials met our criteria and were, therefore, included. The methodologic quality of these trials was variable but, on average, was low. For cutaneous pain and diarrhea, encouraging evidence exists that warrants further investigation in rigorous trials. Single studies reported some positive intergroup differences for spinal cord injury, Cushing's syndrome, lung function, hepatitis, and rumen acidosis. These trials require independent replication. On the basis of the findings of this systematic review, there is no compelling evidence to recommend or reject acupuncture for any condition in domestic animals. Some encouraging data do exist that warrant further investigation in independent rigorous trials. 相似文献
138.
Ten newly isolated hop proanthocyanidin oligomers and flavan-3-ol monomers from 13 different hops have been identified as gallocatechin, gallocatechin-(4alpha-->8)-catechin, gallocatechin-(4alpha-->6)-catechin, catechin-(4alpha-->8)-gallocatechin, catechin-(4alpha-->6)-gallocatechin, afzelechin-(4alpha-->8)-catechin, catechin-(4alpha-->8)-catechin-(4alpha-->8)-catechin, epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-catechin, catechin-(4alpha-->8)-gallocatechin-(4alpha-->8)-catechin, and gallocatechin-(4alpha-->8)-gallocatechin-(4alpha-->8)-catechin, together with seven previously isolated oligomers, namely, catechin, epicatechin, epicatechin-(4beta-->8)-catechin, epicatechin-(4beta-->8)-epicatechin, catechin-(4alpha-->8)-catechin, catechin-(4alpha-->8)-epicatechin, and epicatechin-(4beta-->8)-catechin-(4alpha-->8)-catechin. These compounds were subjected to acid-catalyzed degradation in the presence of phloroglucinol or by partial or complete acid-catalyzed degradation and reaction with benzyl mercaptan followed by desulfurization. The resultant adducts when compared to authentic samples by high-performance liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometry and high-performance liquid chromatography-electrospray ionization tandem mass spectrometry served to identify the precursors. The composition of proanthocyanidins from 13 different hops was similar, but the concentration of individual compounds showed some differences, which indicated that hop proanthocyanidin profiles are affected by geographic origin and are variable depending on the cultivars. 相似文献
139.
ABSTRACT Pyrenophora teres, the causal agent of net blotch of barley (Hordeum vulgare L.), induces a combination of necrosis and extensive chlorosis in susceptible barley cultivars. Cell-free filtrates from both net and spot forms of P. teres; P. teres f. sp. teres, and P. teres f. sp. maculata were found to contain phytotoxic low molecular weight compounds (LMWCs) and proteinaceous metabolites which appear to be responsible for different components of the symptoms induced by the two forms of the pathogen in a susceptible cultivar of barley (cv. Sloop). Proteins induced only brown necrotic spots or lesions similar to those induced by the pathogens 72 h after inoculation. In contrast, LMWCs induced general chlorosis seen 240 h after inoculation but not the localized necrosis. Neither hydrolyzed or heat- or protease-treated proteinaceous metabolites induced the symptoms. This is the first report of the involvement of proteins produced by P. teres in symptom development during net blotch disease of barley. 相似文献
140.
Rice CP Baldwin Vi RL Abbott LC Hapeman CJ Capuco AV Le A Bialek-Kalinski K Bannerman DD Hare WR Paape MJ McCarty GW Kauf AC Sadeghi AM Starr JL McConnell LL Van Tassell CP 《Journal of agricultural and food chemistry》2007,55(21):8806-8813
Perchlorate has been detected in U.S. milk samples from many different states. Applying data from a recently reported 9-week experiment in which 16 Holstein dairy cows were administered perchlorate allowed us to derive an equation for the dose-response relationship between perchlorate concentrations in feed/drinking water and its appearance in milk. Examination of background concentrations of perchlorate in the total mixed ration (TMR) fed in addition to the variable dose supplied to treated cows as a ruminal infusate revealed that cows receive significant and variable exposure to perchlorate from the TMR. Weekly examination of the TMR disclosed that a change in ingredients midway through the experiment caused a significant (78%) change in TMR perchlorate concentration. Analyses of the ingredients comprising the TMR revealed that 41.9% of the perchlorate came from corn silage, 22.9% came from alfalfa hay and 11.7% was supplied by sudan grass. Finally, USDA Food and Nutrition Survey data on fluid milk consumption were used to predict potential human exposure from milk that contained concentrations of perchlorate observed in our previous dosing study. The study suggests that reducing perchlorate concentration in dairy feed may reduce perchlorate concentrations in milk as well as the potential to reduce human exposure to perchlorate in milk. 相似文献