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71.
Łukasz Stępień Volker Mohler Jan Bocianowski Grzegorz Koczyk 《Genetic Resources and Crop Evolution》2007,54(7):1499-1506
Fifty-three wheat cultivars have been genotyped using 24 SSR (simple sequence repeat) markers in order to evaluate genetic
similarities among Polish wheats, i.e. 53 spring and winter cultivars; ‘Chinese Spring’ was taken as reference. ll but one
SSR marker allowed to identify DNA polymorphisms, giving in total 166 alleles (including nulls), from 3 to 13 alleles per
marker with mean of 7.22. Based on marker data, genetic similarities were calculated and a dendrogram was created. ‘Spring’
cultivars were less diverse than winter ones, showing the biggest similarity to ‘Chinese Spring’. Four sister cultivars (Nutka,
Tonacja, Zyta and Sukces), formed a cluster of very similar materials, of which Zyta and Sukces had the highest similarity
indices. Parental lines Jubilatka and SMH 2182 were more distant from each other (genetic similarity of 0.227). It was possible
to differentiate all the wheats using only four SSR markers: Xgwm186, Xgwm389, Xgwm459 and Xgwm577. 相似文献
72.
73.
The objectives of this study were to determine if sires perform consistently across altitude and to quantify the genetic relationship between growth and survival at differing altitudes. Data from the American Angus Association included weaning weight (WW) adjusted to 205 (n = 77,771) and yearling weight adjusted to 365 (n = 39,450) d of age from 77,771 purebred Angus cattle born in Colorado between 1972 and 2007. Postweaning gain (PWG) was calculated by subtracting adjusted WW from adjusted yearling weight. Altitude was assigned to each record based upon the zip code of each herd in the database. Records for WW and PWG were each split into 2 traits measured at low and high altitude, with the records from medium altitude removed from the data due to inconsistencies between growth performance and apparent culling rate. A binary trait, survival (SV), was defined to account for censored records at yearling for each altitude. It was assumed that, at high altitude, individuals missing a yearling weight either died or required relocation to a lower altitude predominantly due to brisket disease, a condition common at high altitude. Model 1 considered each WW and PWG measured at 2 altitudes as separate traits. Model 2 treated PWG and SV measured as separate traits due to altitude. Models included the effects of weaning contemporary group, age of dam, animal additive genetic effects, and residual. Maternal genetic and maternal permanent environmental effects were included for WW. Heritability estimates for WW in Model 1 were 0.28 and 0.26 and for PWG were 0.26 and 0.19 with greater values in low altitude. Genetic correlations between growth traits measured at different altitude were moderate in magnitude: 0.74 for WW and 0.76 for PWG and indicate possibility of reranking of sires across altitude. Maternal genetic correlation between WW at varying altitude of 0.75 also indicates these may be different traits. In Model 2, heritabilities were 0.14 and 0.27 for PWG and 0.36 and 0.47 for SV. Genetic correlation between PWG measured at low and high altitude was 0.68. Favorable genetic correlations were estimated between SV and PWG within and between altitudes, suggesting that calves with genetics for increased growth from weaning to yearling also have increased genetic potential for SV. Genetic evaluations of PWG in different altitudes should consider preselection of the data, by using a censoring trait, like survivability to yearling. 相似文献
74.
This paper reports the modification/degradation of lignin within spruce sawdust by manganese complexes formed by the association of MnO(2) and oxalate. The Mn oxidants formed are shown to modify both the chemical and physical properties of the wood cell wall. Scanning electron microscopy analysis of oxidized tracheids revealed a smoothing of the cell wall surface from the lumen side due to the removal of some material. Thioacidolysis analysis of the oxidized lignin showed reductions of up to 30% in the recovery of ether-linked guaiacyl monomers and up to 45% for the some dimers composing the polymer. The MnO(2)/oxalate system also slightly modified polysaccharides, corresponding to a 10% loss in weight of arabinose and glucose in the oxidized sample. However, no delignification occurred, according to the acid insoluble lignin content of spruce. Oxalic acid at pH 2.5 did not induce detectable changes in the chemical structures of the lignin or of the polysaccharides. 相似文献
75.
The Usefulness of Captive Kept Capercaillie (Tetrao urogallus L.) as the Semen Donors for Artificial Insemination and Gene Pool Preservation In vitro
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Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106 per ml to 3520 × 106 per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons. 相似文献
76.
Netto Benetti MR Rudnicki M Zanotto-Filho A de Oliveira MR Kurek AG Coitinho A Schwartsmann G Moreira JC 《Fitoterapia》2007,78(3):232-234
The ethanolic extract of Symphyopappus casarettoi syn. Eupatorium casarettoi was partionated in hexanic, chloroformic and methanolic fractions. Extract and fractions were tested for their antioxidant activity in vitro and ex vivo assays. The methanolic fraction showed a higher antioxidant potential compared to the others fractions, which was correlated with its total phenol content. In addition, the ethanolic extract and the methanolic fraction attenuated ex vivo iron-induced cell death, quantified by lactate dehydrogenase leakage, and effectively protected against lipid damage induced by iron. These findings suggest that the ethanolic extract of S. casarettoi inflorescence and its methanolic fraction have in vitro and ex vivo antioxidant properties. 相似文献
77.
Elżbieta Kondera Katarzyna Ługowska Piotr Sarnowski 《Fish physiology and biochemistry》2014,40(1):9-22
The aim of the present study was to evaluate bioaccumulation of metals in various tissues of the freshwater fish Cyprinus carpio L. exposed to cadmium and copper (a xenobiotic and a microelement). The fish were subjected to short-term (3 h, Cd-S and Cu-S) or long-term (4 weeks, Cd-L and Cu-L) exposures to 100 % 96hLC50 or 10 % 96hLC50, respectively. Blood, gill, liver, head and trunk kidney were isolated weekly from 5 fish of each group for 4 weeks (post-short-term exposure and during long-term exposure). Atomic absorption spectrophotometry technique was applied to measure concentrations of metals (Cd and Cu) in fish tissues. Initial concentrations of copper in fish tissues were higher than levels of cadmium. Cadmium and copper levels increased in all tissues of metal-exposed fish. After short-term exposures (at higher concentration) and during long-term exposures (at lower concentration), similar changes in metal concentrations were observed. The values of accumulation factor (ratio of final to initial metal concentration) were higher for cadmium as compared to copper. Comparison of metal levels and accumulation factors in various tissues revealed that cadmium and copper showed very high affinity to head kidney of common carp (higher than to other tissues), but accumulation factors for cadmium in trunk, head kidney and liver were much higher than for copper. The concentrations of copper in organs of Cu-exposed fish increased only slightly and quickly returned to the control level, which shows that fish organism easily buffered metal level. On the other hand, concentrations of cadmium considerably increased and remained elevated for a long time which suggests that activation of mechanisms of sequestration and elimination of cadmium required more time. 相似文献
78.
79.
Katarzyna Czaja Katarzyna Góralczyk Paweł Struciński Agnieszka Hernik Wojciech Korcz Maria Minorczyk Monika Łyczewska Jan K Ludwicki 《Pest management science》2015,71(1):3-6
The introduction of new food safety regulations in the European Union has resulted in the withdrawal of many synthetic active substances used in plant protection products, in light of their potential or actual harmful effect on human and animal health, as well as on the environment. Alternatives to these compounds are being developed – naturally occurring pesticides, also referred to as biopesticides. The use of biopesticides in crop protection leads to decreased levels of pesticide residues in foods, and as a result to lower risk levels for the consumer. Biologically active agents defined as biopesticides are varied, and therefore application of the same environmental and consumer safety criteria to all of them is impossible. This presents serious complications in the approval of these pesticides as active plant protection products and in their registration. It needs to be stressed that, in the registration procedure of the European Union, biopesticides are subject to the same regulations as synthetic active substances. This situation has resulted in the need to introduce numerous new provisions in the legislation, as well as the preparation of new guidelines facilitating the registration of biopesticides. These activities aim to promote naturally originating pesticides. © 2014 Society of Chemical Industry 相似文献
80.
Copper and lead accumulation in common carp females during long‐term dietary exposure to these metals in pond conditions
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Ewa Łuszczek‐Trojnar Jan Sionkowski Ewa Drąg‐Kozak Włodzimierz Popek 《Aquaculture Research》2016,47(7):2334-2348
The aim of the research was to observe the process of copper and lead accumulation in tissues of adult females of the common carp, during a long‐time (3 years) dietary exposure to these metals in pond conditions. The fish were divided into 3 groups, which were fed with control pellets (control group) and pellets contaminated with lead (group Pb, 68.4 mg Pb kg?1dry weight) or copper (group Cu, 153.1 mg Cu kg?1) for three exposure periods: the first, the second and the third vegetation seasons. Quite a different profile of tissue metal accumulation was observed for copper and for lead in female carps. Copper accumulates mainly in the liver (205.4 ± 35.2 mg kg?1), reaching values 70 times higher than in control, and 300 times higher than in some other tissues, while lead accumulated mainly in the kidney (1.7 ± 0.25 mg kg?1) and intestine (2.2 ± 0.2 mg kg?1). Even when exposed to Cu or Pb for three consecutive seasons, the carps studied did not accumulate these metals in the muscles at the level dangerous for human health in case of ingestion. 相似文献