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21.
Arabis mosaic virus (ArMV) is an important pathogen infecting a wide range of plant species worldwide. In the present study, we carried out exhaustive phylogenetic analyses based on the coat protein (CP) sequence of ArMV isolates originating from different host plants and geographic regions. Maximum-likelihood reconstruction revealed the presence of three distinct, well-supported phylogroups. BaTS analyses indicated that the diversity of ArMV isolates may be correlated with both host plant and geographic origin. Moreover, population genetic analyses showed significant differences in the level of genetic diversity among variants within ArMV that originated from rhubarb plants, as expected by quasispecies. Further analysis revealed that both selection and recombination are shaping the population structure of ArMV. In total 14 groups of residues were detected as coevolving for different amino acid properties. 相似文献
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Genetic diversity and population structure of Polish Arabian horses assessed through breeding and microsatellite data 下载免费PDF全文
Iwona Głażewska Barbara Gralak Aleksandra M. Naczk Beata Prusak 《Animal Science Journal》2018,89(5):735-742
Polish Arabian horses are one of the most important populations of this breed in the world. Their post‐war history can be divided into two periods, with the dominant role of state studs until 1989, and the increasing significance of private breeding in the next years. The goal of the study was to evaluate genetic diversity and structure of the population under a new breeding policy. The analyses of breeding and microsatellite data from 1996 to 2012 provide a coherent picture of the population with constant flow of horses only in one direction from state to private studs. An increase in the number of broodmares was observed, from 396 mares in 1996 to 1021 mares in 2012. The proportion of foreign sires used in Polish studs also increased, from 7.1% to 37.0%. An increasing number of alleles and progressive differentiation in mares were observed. STRUCTURE analysis indicated that the Polish horses were clearly separated from foreign horses used in Polish breeding, although only one of the 75 alleles found can be considered as typically Polish. The high heterozygosity is an important feature of the Polish population; however, the decrease of heterozygosity in state broodmares was noted. This issue needs to be studied further. 相似文献
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Daria Budzyńska Julia Minicka Beata Hasiów-Jaroszewska Santiago F. Elena 《Plant pathology》2020,69(9):1767-1776
Tomato black ring virus (TBRV) is a worldwide-distributed RNA virus infecting a wide range of different host plants, including crop species, trees, shrubs, and weeds. Here, we investigated the molecular evolution of TBRV and its adaptability to different plant species. The TBRV-Pi isolate was used to generate five independent evolution lineages serially passaged in either quinoa, tobacco, or tomato plants. After 15 passages, the genetic variability present in all the lineages was characterized for the movement (MP) and coat (CP) coding cistrons. We addressed two main questions: to what extent does the amount of genetic variability in the TBRV genome depend on the host species, and are there host species-specific adaptive mutations? Overall, 201 different nucleotide substitutions emerged during the evolution experiment, with some of them appearing multiple times in different lineages; two of them (one in CP and one in MP) were unique for a particular host plant. We have shown that the degree of genetic differentiation depends on the host species in which the virus evolved, and that positive selection is operating upon certain residues, particularly in CP. Moreover, we have characterized new types of defective RNAs that arose during the TBRV-Pi evolution in tobacco. Furthermore, this is the first report of a defective RNA from the RNA2 of TBRV. 相似文献
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Dariusz Piwczyski Beata Sitkowska Magdalena Kolenda Marcin Brzozowski Joanna Aerts Pamela M. Schork 《Animal Science Journal》2020,91(1)
The purpose of this paper was to utilize the decision trees technique to determine the factors responsible for high monthly milk yield in Polish Holstein‐Friesian cows from 27 herds equipped with milking robots. The applied statistical method—the decision tree technique—showed that the most important factors responsible for monthly milk yield of dairy cows using robots were, in descending order of importance: milking frequency, lactation number, month of milking, and type of lying stall. At the same time, it has been ascertained that the highest monthly milk yield (47.24 kg) can be expected from multiparous cows kept in barns with a deep bedding that were milked more frequently than three times per day. On the other hand, the lowest milk production (13.56 kg) was observed among dairy cows milked less frequently than two times a day, with an average number of milked quarters lower than 3.97. The application of the decision trees technique allows a breeder to select appropriate levels of environmental factors and parameters that will help to ensure maximized milk production. 相似文献
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Szafranek B Chrapkowska K Waligóra D Palavinskas R Banach A Szafranek J 《Journal of agricultural and food chemistry》2006,54(20):7729-7734
The structures of two previously unknown sesquiterpene alcohols of the potato (Solanum tuberosum) were assigned. The potato alcohols were obtained by steam-distillation, preparative column chromatography, and separation into fractions by HPLC on a silica gel column. The fractions were studied by GC-FID, GC-MS, and NMR spectroscopy. The potato sesquiterpene alcohols were identified as kunzeaol (6-alpha-hydroxygermacra-1(10),4-diene) and ledol. These two compounds were used in feeding tests with larvae and beetles of the Colorado potato beetle (Leptinotarsa decemlineata Say). In a bioassay, kunzeaol was found to act as a feeding attractant for the beetles. 相似文献
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Giorgi M Saccomanni G Lebkowska-Wieruszewska B Kowalski C 《Veterinary journal (London, England : 1997)》2009,180(2):253-255
The study evaluated the pharmacokinetics of tramadol and its major metabolites O-desmethyltramadol (M1), N-desmethyltramadol (M2) and N-O didesmethyltramadol (M5) following a single oral administration of a sustained release (SR) 100mg tablet to dogs. Plasma tramadol concentration was greater than the limit of quantification (LOQ) in three dogs, M1 was quantified only in one dog while M2 and M5 were quantified in all of the dogs. The median values of C(max) (maximum plasma concentration), T(max) (time to maximum plasma concentration) and T(1/2) (half-life) for tramadol were 0.04 (0.17-0.02)mirog mL(-1), 3 (4-2) and 1.88 (2.211-1.435)h, respectively. M5 showed median values of C(max), T(max) and T(1/2) of 0.1 (0.19-0.09)microg mL(-1), 2 (3-1) and 4.230 (6.583-1.847)h, respectively. M2 showed median values of C(max), T(max) and T(1/2) of 0.22 (0.330-0.080)microg mL(-1), 4 (7-3) and 4.487 (6.395-1.563)h, respectively. The findings suggest that the SR formulation of tramadol may not have suitable pharmacokinetic characteristics to be administered once-a-day as an effective and safe treatment for pain in the dog. 相似文献
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Dorota Milczarek Anna Podlewska-Przetakiewicz Jarosaw Plich Beata Tatarowska Bogdan Flis 《Breeding Science》2021,71(5):609
Cultivating resistant varieties of potato is the most effective and environmentally sound method of protecting potato crops against pests and diseases. Potato cyst nematodes (PCN) are major nematode pests causing severe constraints in potato production worldwide. There are five pathotypes of Globodrea rostochiensis (Ro1–Ro5) and three of G. pallida Pa1–Pa3. Cultivation of potato varieties with broad nematode resistance may influence the growth of the wide spectrum of PCN pathotypes, but there is limited availability of such varieties on the market. The use of molecular markers allows for the effective selection of resistant genotypes at early stages of breeding. However, the impact of early selection for nematode resistance on the agronomic value of the final selected clones is a cause of concern for potato breeders. This study investigates the relationships between the presence of the combined resistance genes H1, Gro1-4 and GpaVvrn, which confer resistance to the nematodes, and certain agricultural traits. Clones with broad nematode resistance conferred by the genes H1, Gro1-4 and GpaVvrn presented yields and tuber morphology traits similar to those of the clones without identified resistance genes. 相似文献
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