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61.
橡胶树品种热研88-13易碎胚性愈伤组织的诱导及其植株再生 总被引:1,自引:0,他引:1
以高产优质橡胶品种热研88-13的幼嫩种子内珠被为外植体材料,对愈伤组织诱导培养基和继代培养基中的影响因素如植物生长调节剂的种类和浓度、钙离子浓度等进行了研究。经过连续6个月的继代选择培养,逐渐诱导出易碎的胚性愈伤组织,适宜的易碎胚性愈伤组织诱导培养基为:MH基本成分,添加0.5 mg/L KT,2.0 mg/L 2,4-D,11.0 mmol/L CaCl2,80.0 g/L蔗糖和2.0 g/L Phytagel。组织学切片证明长期继代培养的易碎胚性愈伤组织维持了胚性的状态。取继代培养2 a多的易碎胚性愈伤组织诱导体细胞胚的形成,得到了16 000多个体细胞胚。将这些胚进行进一步的转移培养,得到了115株再生植株。 相似文献
62.
Thibaut Olivier Vaidevutis Šveikauskas Elisabeth Demonty Kris De Jonghe Pascal Gentit Mojca Viršček-Marn Sabine Grausgruber-Gröger Sébastien Morio Francesco Faggioli Michèle Visage Frédéric Fauche Maria Gusina Marta Luigi Helena Lasner Irena Mavrič-Pleško 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(3):645-654
63.
Pascal Castellazzi Guy Mercier Jean-François Blais 《Water, air, and soil pollution》2012,223(1):337-349
Cocamidopropyl hydroxysultaine (CAS) has been used in a pilot plant study as a biodegradable surfactant for the extraction
of polycyclic aromatic hydrocarbons (PAHs) and lead (Pb) from contaminated soils. The soil treatment has been done in flotation
cells with a concentration of 0.20 g CAS L−1 in saline conditions (3 M NaCl) and using a pulp density of 20% (w/w). The process integrates the recirculation of the liquid phases separated from the soil by centrifugation or filtration.
Thus, it was necessary to understand CAS-PAHs micellar behavior and to follow the behavior and the fate of the surfactant
in the process. 1-8-anilino-naphthalene sulfonate (ANS) is used as a fluorophor compound in the ANS enhanced fluorescence
technique. A three-dimensional model detailing the change in the micellar behavior at high NaCl concentration and at different
pH has been established. Fluorescence results of centrifuged soil matrix containing CAS have been compared to the results
from synthetic solutions assays. A method allowing an accurate titration of the CAS has been developed by using the exact
same matrix of the soil as the tested samples for the preparation of the calibration curves. The study of the surfactant concentration
in the process has been performed and allows the adjustment of the CAS concentration in the recirculated water. 相似文献
64.
Pascal Jouquet Ga?lle Huchet Nicolas Bottinelli Thuy Doan Thu Toan Tran Duc 《Biology and Fertility of Soils》2012,48(5):561-567
Soil compaction has a negative impact on both earthworm abundance and diversity. Recent studies, however, suggest that earthworm cast properties are not influenced by the initial soil bulk density. With time, earthworms could therefore transform soils with different bulk densities into a soil with the same physical state and thus with a similar ecological functioning. This study aimed to test this hypothesis in two laboratory incubation experiments. First, we measured the influence of soil bulk density (1.1 or 1.4?g?cm?3) on the production of cast by the endogeic earthworm species Metaphire posthuma. In a second experiment, we investigated the effect of M. posthuma on water infiltration, NH 4 + , and NO 3 ? leaching and soil respiration at the same two soil bulk densities. Although initially higher, earthworm casting activity in soil at 1.4?g?cm?3 decreased until it reached the same level of activity as earthworms in soil at 1.1?g?cm?3. This behavioral plasticity led to a transformation of compacted and loose soils, with their own functioning, to a third and similar state with similar hydraulic conductivity, nitrogen leaching, and soil respiration. The consequences for soil organization and soil functioning are discussed. 相似文献
65.
Andraud M Rose N Laurentie M Sanders P Le Roux A Cariolet R Chauvin C Jouy E 《Veterinary research》2011,42(1):44
Antimicrobial resistance is of primary importance regarding public and animal health issues. Persistence and spread of resistant strains within a population contribute to the maintenance of a reservoir and lead to treatment failure. An experimental trial was carried out to study the horizontal transmission of a fluoroquinolone-resistant Escherichia coli strain from inoculated to naïve pigs. All naïve contact pigs had positive counts of fluoroquinolone-resistant E. coli after only two days of contact. Moreover, re-infections of inoculated pigs caused by newly contaminated animals were suspected. A maximum likelihood method, based on a susceptible-infectious-susceptible (SIS) model, was used to determine the transmission parameters. Two transmission levels were identified depending on the quantity of bacteria shed by infected individuals: (i) low-shedders with bacterial counts of resistant E. coli in the faeces between 5*103 and 106 CFU/g (βL = 0.41 [0.27; 0.62]), (ii) high shedders with bacterial counts above 106 CFU/g (βH = 0.98 [0.59; 1.62]). Hence, transmission between animals could be pivotal in explaining the persistence of resistant bacteria within pig herds. 相似文献
66.
Ducrot C Bed'hom B Béringue V Coulon JB Fourichon C Guérin JL Krebs S Rainard P Schwartz-Cornil I Torny D Vayssier-Taussat M Zientara S Zundel E Pineau T 《Veterinary research》2011,42(1):96
ABSTRACT: In the rapidly changing context of research on animal health, INRA launched a collective discussion on the challenges facing the field, its distinguishing features, and synergies with biomedical research. As has been declared forcibly by the heads of WHO, FAO and OIE, the challenges facing animal health, beyond diseases transmissible to humans, are critically important and involve food security, agriculture economics, and the ensemble of economic activities associated with agriculture. There are in addition issues related to public health (zoonoses, xenobiotics, antimicrobial resistance), the environment, and animal welfare.Animal health research is distinguished by particular methodologies and scientific questions that stem from the specific biological features of domestic species and from animal husbandry practices. It generally does not explore the same scientific questions as research on human biology, even when the same pathogens are being studied, and the discipline is rooted in a very specific agricultural and economic context.Generic and methodological synergies nevertheless exist with biomedical research, particularly with regard to tools and biological models. Certain domestic species furthermore present more functional similarities with humans than laboratory rodents.The singularity of animal health research in relation to biomedical research should be taken into account in the organization, evaluation, and funding of the field through a policy that clearly recognizes the specific issues at stake. At the same time, the One Health approach should facilitate closer collaboration between biomedical and animal health research at the level of research teams and programmes. 相似文献
67.
Franssen FF Fonville M Takumi K Vallée I Grasset A Koedam MA Wester PW Boireau P van der Giessen JW 《Veterinary research》2011,42(1):113
ABSTRACT: Domestic pigs are the main representatives of the domestic cycle of Trichinella spiralis that play a role in transmission to humans. In Europe, backyard pigs of small household farms are the most important risks for humans to obtain trichinellosis. Rats might play a role in the transmission of Trichinella spiralis from domestic to sylvatic animals and vice versa. In order to be able to investigate the role of wild rats in the epidemiology of T. spiralis in The Netherlands, we studied the dynamics of antibody response after T. spiralis infections in experimental rats, using infection doses ranging from very low (10 muscle larvae, ML, per rat) to very high (16 000 ML per rat). To evaluate the feasibility of rats surviving high infection doses with T. spiralis, clinical and pathological parameters were quantified. Serological tools for detecting T. spiralis in rats were developed to quantitatively study the correlation between parasite load and immunological response. The results show that an infection dose-dependent antibody response was developed in rats after infection with as low as 10 ML up to a level of 10 000 ML. A positive correlation was found between the number of recovered ML and serum antibody levels, although specific measured antibody levels correspond to a wide range of LPG values. Serum antibodies of rats that were infected even with 10 or 25 ML could readily be detected by use of the T. spiralis western blot 2 weeks post infection. We conclude that based on these low infection doses, serologic tests are a useful tool to survey T. spiralis in wild rats. 相似文献
68.
Savary P Gygax L Jungbluth T Wechsler B Hauser R 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(1-2):17-21
In this pilot study, we tested whether a soft mat (foam covered with a heat-sealed thermoplastic) reduces alterations and injuries at the skin and the leg joints.The soft mat in the lying area of partly slatted pens was compared to a lying area consisting of either bare or slightly littered (100 g straw per pig and day) concrete flooring. In this study we focused on skin lesions on the legs of finishing pigs as indicators of impaired welfare. Pigs were kept in 19 groups of 8-10 individuals and were examined for skin lesions around the carpal and tarsal joints either at a weight of <35 kg, or at close to 100 kg. The likelihood of hairless patches and wounds at the tarsal joints was significantly lower in pens with the soft lying mat than in pens with a bare concrete floor. Pens with a littered concrete floor did not differ compared to pens with a bare concrete floor. The soft lying mat thus improved floor quality in the lying area in terms of preventing skin lesions compared to bare and slightly littered concrete flooring. Such soft lying mats have thus the potential to improve lying comfort and welfare of finishing pigs. 相似文献
69.
70.
Sandy Adriaenssens Jeroen Staelens Karen Wuyts An de Schrijver Shari Van Wittenberghe Tatiana Wuytack Fatemeh Kardel Kris Verheyen Roeland Samson Pascal Boeckx 《Water, air, and soil pollution》2011,219(1-4):43-57
This study assessed the foliar uptake of 15N-labelled nitrogen (N) originating from wet deposition along with leaf surface conditions, measured by wettability and water storage capacity. Foliar 15N uptake was measured on saplings of silver birch, European beech, pedunculate oak and Scots pine and the effect of nitrogen form (NH 4 + or NO 3 ? ), NH 4 + to NO 3 ? ratio and leaf phenology on this N uptake was assessed. Next to this, leaf wettability and water storage capacity were determined for each tree species and phenological stage, and the relationship with 15NH 4 + and 15NO 3 ? uptake was examined. Uptake rates were on average five times higher (p?<?0.05) for NH 4 + than for NO 3 ? and four times higher for deciduous species than for Scots pine. Developing leaves showed lower uptake than fully developed and senescent leaves, but this effect was tree species dependent. The applied NH 4 + to NO 3 ? ratio did only affect the amount of N uptake by senescent leaves. The negative correlation between measured leaf contact angles and foliar N uptake demonstrates that the observed effects of tree species and phenological stage are related to differences in leaf wettability and not to water storage capacity. 相似文献