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1.
Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. Black locust plants are commonly produced by two methods, by seed and by root cuttings. Tissue culture propagation can be considered as a relatively new method. Growing trees from seed is a relatively simple method for reliably producing seedlings on a large scale under a variety of circumstances. Mechanization of the method is easy and the production cost is relatively low. Propagation from root cuttings and tissue culture are valuable for reproduction of superior individuals or varieties. By applying these methods, superior traits of the selected trees can be preserved in the clones. Recent experiments demonstrated that micropropagated trees could be successfully transplanted into soil, hardened and grown in the field. Biography: Karoly Redei (1952), male, doctor, deputy director general of Hungarian Forest Research Institute H-1023 Budapest, Frankel Leó Str. 42 44, HUNGARY. Responsible editor: Chal Ruihai  相似文献   
2.
Visceral leishmaniasis in captive wild canids in Brazil   总被引:1,自引:1,他引:0  
Visceral leishmaniasis (VL) is endemic in Belo Horizonte (State of Minas Gerais, Brazil). Leishmania sp. can naturally infect several species of mammals, and the domestic dog is the most important reservoir of the disease in South America. This report describes five cases of visceral leishmaniasis in Brazilian canids. Among 15 animals kept in captivity in a zoo in Belo Horizonte (State of Minas Gerais, Brazil), two animals, a bush dog (Spheotos venaticos) and a hoary zorro (Lycalopex vetulus) were serologically positive and developed clinical signs of VL, whereas three other canids, including a crab-eating fox (Cerdocyon thous), a maned wolf (Chrysocyon brachyurus), and a hoary zorro (Lycalopex vetulus) had positive serological results without clinical signs.  相似文献   
3.
Structure-activity relationships of aryl alkynyl synergists of the general formula of Ar-Q-R, where Q represents a bridging structure, were studied using a standardised testing system and Relative Potency values. Ethers, esters, oxime ethers, amides and amines were prepared and evaluated. The length of the R-alkynyl chain, the role of the bridge and the substitution of the aromatic ring were examined systematically. The most potent compounds possessed an aromatic ring connected via a bridge of three atoms to an alkynyl chain, forming together a linear side-chain of six atoms. Several highly potent compounds were synthesised of which one (MB-599; proposed common name verbutin) was selected for development as a selective insecticide synergist in crop protection. Its high potential at practical insecticide:synergist ratios makes possible the reduction of the total amount of insect-control chemicals applied, and its use as an additive to produce new formulations of existing insecticides makes it highly advantageous in resistance management, giving a new tool to sustain the effectiveness of a wide range of insecticides. A product containing a (1+1) mixture of verbutin and beta-cypermethrin was launched in Hungary in 2002.  相似文献   
4.
This study was designed to determine the effects of calcium salt of palm oil fatty acids (CS), hydroxyethylsoyamide (HESA), butylsoyamide (BSA) and soybean oil (SO) on degradation of crude protein and fibre in vitro, and on the blood plasma lipid parameters in vivo. Five mature wethers (body weight 75 kg) were fed five diets in a 5 x 5 Latin square experiment. The control diet consisted of 50% meadow hay and 50% concentrate with no added fat. The control diet was supplemented with CS, HESA, BSA, or SO. Fat was added at 3.5% of dietary dry matter (DM). The final ether extract content of the ration was near 6%. Each period lasted 20 days. Fat supplements, except HESA, consistently decreased the in vitro DM disappearance of soybean meal as compared to control. In contrast to the effect of other treatments, crude protein degradation was greatest in the test tubes with inocula obtained from sheep fed diet with HESA. Fat supplements equally inhibited the DM and fibre breakdown of alfalfa pellet. CS and HESA seemed to be less detrimental to in vitro fermentation of neutral detergent fibre (NDF) than BSA and SO. All fat supplements increased blood plasma triglyceride, cholesterol and total lipid content. Plasma concentration of cholesterol and total lipid was highest with SO. The inclusion of CS in the diet increased 16:0, while all fat supplements increased plasma 18:0 and decreased 16:1 and 18:1 fatty acid content. Plasma 18:2n-6 was not changed by feeding CS and SO. However, compared to the control diet, 18:2n-6 increased with 12 and 41% in plasma fatty acids when sheep were fed HESA and BSA, respectively. The results showed that plasma concentration of linoleic acid was enhanced more when the amide was synthesised from butylamine than when from ethanolamine.  相似文献   
5.
Different molecular markers are routinely used in studies of potato (Solanum tuberosum) and the genus Solanum in general. Genome sequence databases provide potential to design new markers for various applications. Here we present the application of a recently developed core set of nuclear intron-targeting (indel) markers. These markers are based on the fact that in the plant genome introns are more variable than exons; therefore primers flanking exons can reveal polymorphisms related to introns. We detected such variation among accessions of the eight different species of black nightshades (Solanum sect. Solanum). Members of this group are important sources of food, mostly in Africa, while others are poisonous weeds with near global distribution. The tested 29 primers were designed previously for potato based on Solanaceae EST and other genomic databases and targeted 16 different genes. Our results showed that Solanum intron-targeting markers are not very polymorphic but identified considerable structure among accessions indicating fairly high interspecies differentiation. Further analyses showed that inbreeding is unlikely to be the major driving force in determining the genetic structure of the analyzed species. All phylogenetic analyses resolved the species included in our study as distinct clades with high support values, but provided weak information about their internal relationships. In summary, indel markers would be useful for the assignment of new Solanum germplasm to taxonomic groups or to identify certain taxa. They could also be used to address important question about genetic diversity and should yield results comparable to other markers covering the whole genome.  相似文献   
6.
A total of 205 cornflake samples collected in Belgian retail stores during 2003-2004 were surveyed for the natural occurrence of fumonisin B1 (FB1), B2 (FB2), and B3 (FB3). These cornflake samples, originating from conventional as well as from organic production, were analyzed using an intralaboratory-validated LC-MS/MS method. Additionally, 90 cornflake samples were subjected to rapid screening using a flow-through enzyme immunoassay method to demonstrate the practicability of a screening test coupled to a validated confirmatory LC-MS/MS method for the management of food safety risks. FB(1) concentrations ranged from not detected (nd) [LOD (FB1) = 20 microg/kg] to 464 microg/kg with mean and median concentrations of respectively 104 +/- 113 and 54 microg/kg. For FB2 and FB3, the concentration ranges varied respectively from nd [LOD (FB2) = 7.5 microg/kg] to 43 microg/kg and from nd [LOD (FB3) = 12.5 microg/kg] to 90 microg/kg. Mean concentrations for FB2 and FB3 were respectively 12 +/- 8 and 21 +/- 15 microg/kg, while the median concentration was 11 microg/kg for FB2 and 19 microg/kg for FB3. From the statistical tests (chi2 and ANOVA model III), it could be concluded that the agricultural practice did not have any significant effect on the fumonisin concentrations but that the variation between different batches was significant (p < 0.0001).  相似文献   
7.
Achieving a sustainable increase in the fertility of sandy soils is a major problem. The application of biochar (BC) is a relatively new method, but results for a temperate climate are scarce. This work investigates various combined doses of BC and plant growth-promoting rhizobacteria inoculants on the fertility of acidic and calcareous sandy soils, hypothesising that joint application could have a synergistic impact. The effects were followed by measuring chemical (pH, organic matter, nutrient availability) and microbiological properties of the soil and maize biomass. 30 t ha?1 BC increased both pH (by 1 unit) and nitrification in acidic soil (causing a 60% drop in NH4-N concentration), and the phosphorus and potassium availability (by 53 and 80%, respectively) in both soils. Substrate-induced respiration increased by up to 100% and 50% in acidic and calcareous soil, respectively, in treatments involving both BC and inoculant. In acidic soil a BC dose of 3 t ha?1 resulted in a 70% decrease in arbuscular mycorrhizal fungal infection. Changes in maize grain yield were not significant, but the increase in above-ground biomass indicated that the combined application of BC and inoculant is more beneficial than separate application of these yield-increasing agents, primarily on acidic sand.  相似文献   
8.
Vitrification of in vitro matured oocytes of Mangalica and Large White pigs   总被引:1,自引:0,他引:1  
The breeding of Mangalica, a native pig breed in Hungary, had been started in 1833, but this pig breed almost became extinct in Hungary in the past decades. In 1991, the number of sows was only 200. Although in these days the existing Mangalica population consists of more than 6000 animals representing different colour variations, the preservation of this traditional pig breed is still very important. Vitrification is a potential tool for the preservation of gametes and embryos of these animals. The aim of this study was to investigate the effects of vitrification on the developmental competence of Mangalica (M) and Large White (LW) oocytes following fertilisation. The oocytes were vitrified by the Open Pulled Straw (OPS) method using different concentrations of ethylene glycol and dimethyl sulphoxide as cryoprotectants. After rehydration the oocytes underwent in vitro fertilisation; the resultant zygotes were then cultured in vitro for four days to assess embryonic development. In the first experiment, in vitro maturation of M and LW oocytes was compared. No significant difference was observed in the nuclear maturation rate of LW and M oocytes. In the second experiment, the sensitivity of oocytes to vitrification was examined by evaluating oocyte morphology after thawing. A higher percentage of LW oocytes showed normal morphology compared to M oocytes, indicating that Mangalica oocytes are more sensitive to cryoprotectants than Large White oocytes. After warming and in vitro fertilisation, more than 50% of the oocytes started embryonic development and by the end of the incubation period morula stage embryos had developed in both groups. The results show that the OPS vitrification technique is well suited to preserve Mangalica oocytes and from these oocytes morula embryos can be produced.  相似文献   
9.
The heading characters and morphological traits of two partial sets of wheat–barley disomic addition lines, namely Mv9kr1/Igri and Asakaze/Manas, were evaluated under controlled environmental conditions in a phytotron under long-day, short-day and non-vernalised conditions and in field-sown experiments. The winter barley chromosome additions significantly influenced the flowering time of wheat both in the controlled environment test and under field-sown conditions. Of all the barley addition lines, the effect of the 4H and 7H additions was the most characteristic. The 7H addition lines were the earliest in both cultivar combinations in each treatment. In the Mv9kr1/Igri combination the 4H addition was the latest under all the environmental conditions. In the Asakaze/Manas combination 4H addition was the latest under short-day and long-day illumination in the phytotron but the 6H addition was the latest without vernalisation and in the field in 2012. There was 12 and 11 days difference between the flowering times of the 7H and 4H Mv9kr1/Igri and Asakaze/Manas addition lines in the field in 2012, which increased to 52 and 44 days under short-day illumination in the phytotron. In the winter wheat background, the addition of 2H carrying the photoperiod sensitivity gene Ppd-H1 decreased the flowering time under the short photoperiod regime, but had a very strong delaying effect under field-grown conditions. Considering the yield components under field conditions, 4H was the most fertile of the addition lines, while 7H showed the highest tillering capacity, and Igri 3H had good tillering capacity and the highest number of seeds per plant.  相似文献   
10.
A total of 22 samples of apricots belonging to ten cultivars from two locations and picked in the years 1975–78 were assayed for polyphenol oxidase (PPO) and partly for peroxidase (POD) activities, heat resistance of these enzymes,o-dihydroxy phenol (ODP) content, and initial rate of enzymatic browning (BA). Of these characteristics, ODP content showed the greatest and BA the least variation. PPO activity relative to fresh weight was found to depend on the year of harvest rather than on the cultivar, while POD activity relative to fresh weight was cultivar dependent. The values of BA and ODP content were markedly influenced by both cultivar and year. For a given cultivar, PPO and POD activities relative to fresh weight as well as BA were higher in the samples picked in 1976 at one location than in those picked in the other years at the other location.The initial rate of browning of apricots was primarily dependent on the ODP content as shown by linear regression analysis with two independent variables. The relative influence of ODP content as compared with that of PPO activity related to fresh weight was the stronger the higher the value of the ratio of PPO-ODP, i.e. the smaller the values of the endogenous substrate available to the enzyme in the tissues. This suggests substrate depletion to be the limiting factor in the enzymatic browning of apricots.Heat inactivation of PPO was found to be a simple exponential process, while that of POD a biphasic one. PPO was less heat resistant than POD: total inactivation occurred after 10-min heat treatment at 75°C and 85°C, respectively.  相似文献   
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