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1.
Breeding for improved appearance of large rainbow trout in two production environments 总被引：5，自引：0，他引：5
A quantitative genetic analysis was performed to study potential to breed for improved body shape, skin colour and skin spottiness of large rainbow trout in sea and fresh water production environments, and in different stages of growth. The results showed that heritabilities in both production environments were moderate for body shape and skin colour and very high for skin spots. For body shape and skin spots, genetic correlation between the two production environments was high (rA≥0.90), revealing weak genotype‐by‐environment interactions across the environments. For skin colour, genetic correlation between the environments was positive (0.78) but lower than for body shape and skin spots, indicating moderate genotype‐by‐environment interactions. Genetic correlations between 2‐ and 3‐year‐old fish were high for body shape and skin spots (rA≥0.93) and moderate for skin colour (0.85), showing that differences among families persisted strongly during growth. The positive correlations between the environments and between the ages imply that selection in fresh water environment at a single point of time should lead to favourable correlated genetic responses in the sea and at the other stages of growth. 相似文献
2.
Päivi Joki-Heiskala Matti Johansson Maria Holmberg Tuija Mattsson Martin Forsius Pirkko Kortelainen Lena Hallin 《Water, air, and soil pollution》2003,150(1-4):255-273
Long-term base cation balances (Ca, Mg and K) for forest mineral soils in Finland were calculated with mass balance methods. The aim of the study was to identify the areas in which weathering and base cation deposition do not support leaching and uptake of base cations by vegetation. The effect of stem harvesting and whole-tree harvesting on the base cation balances was studied and preliminary calculations were made about the amounts of ash needed for compensation of the potential base cation depletion. The effect of sulphur emission reduction till 2010 was also considered. The study demonstrated that there would be depletion of base cations in forest mineral soils in southern, central and northeastern Finland (40–50% of the grids) in the long term if whole-tree harvesting would be practised. Theoretical calculations showed that ash application would be most useful in those areas to compensate the base cation depletion. If stem harvesting is practised, only small areas (20%) in southwestern and southeastern Finland and northeastern Lapland would show depletion of base cations in the long term. 相似文献
3.
Tuija Pehkonen Janne Koskimki Kaisu Riihinen Anna Maria Pirttil Anja Hohtola Laura Jaakola Anne Tolvanen 《Physiological and Molecular Plant Pathology》2008,72(4-6):146-150
An inoculation method for Exobasidium splendidum and Exobasidium vaccinii was developed on the dwarf shrub Vaccinium vitis-idaea. Using inoculated ramets, we investigated whether there are differences between V. vitis-idaea populations in the susceptibility to Exobasidium infections and whether the defence reaction of V. vitis-idaea is visible at a molecular level. Sixteen V. vitis-idaea clones from four populations were propagated in tissue cultures and the ramets were inoculated with E. splendidum or E. vaccinii fungi. The expression of three flavonoid biosynthetic genes (chalcone synthase, dihydroflavonol 4-reductase and anthocyanidin synthase) and the accumulation of flavonoids and hydroxycinnamic acids were determined in response to E. splendidum infection. A pathogenesis-related (PR 4) gene was isolated and its expression was studied in host ramet leaves. To our knowledge, this was the first successful artificial infection reported with E. splendidum. Disease frequencies of the inoculated ramets were between 32% and 47% for E. splendidum and 33% for E. vaccinii, but below 10% in uninoculated control ramets. There were no differences in disease frequencies between V. vitis-idaea populations. Both symptomatic leaves and healthy leaves of diseased ramets showed activation of flavonoid biosynthesis at the gene level, whereas expression of PR 4 was observed only in symptomatic leaves. The increase of flavonoid biosynthesis in healthy leaves of diseased ramets may represent a general response to stress or a role in defence against the pathogen E. splendidium. Ability of V. vitis-idaea to defend chemically against Exobasidium fungi and the heterogeneity of genotypes, age, size, and growth rates in host plant populations might be reasons for the low infection incidence of Exobasidia in nature. 相似文献
4.
We used in vitro callus and shoot cultures as target material for genetic transformation of silver birch (Betula pendula Roth) by particle bombardment. Cultivation of in vitro shoot cultures before particle bombardment and a long selection period, combined with a high concentration of selective agent after bombardment, led to the production of transformed plantlets that were stable, and no escapes were found among the tree lines produced. Clonal variation in transformation efficiency was found in transient expression of the beta-glucuronidase gene in callus cultures and in plantlets transformed by stable integration of the ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (RbcS) and neomycin phosphotransferase (npt2) genes. 相似文献
5.
Globalisation, in terms of the rapid and free movement of people, animals and food, has created a new paradigm, increasing the range and rate of distribution of many pathogens. In the present study, Torque teno sus viruses (TTSuVs) have been used as a model to evaluate the effects of global trade on viral heterogeneity, and how the movement of live pigs can affect the distribution and composition of virus populations. Seventeen countries from different parts of the world have been screened for TTSuV1 and TTSuvV2. High levels of genetic diversity have been found as well as two new TTSuV subtypes. A small fraction of this diversity (<5%) was related with spatial structure; however the majority (>50%) was best explained by the exchange of live pigs among countries, pointing to the direct relationship between the movement of hosts and the diversity of their accompanying viruses. Taking TTSuVs as sentinels, this study revealed that the distribution and diversity of comensal microflora in live animals subjected to global trade is shaped by the commercial movements among countries. In the case of TTSuVs, it appears that commercial movements of animals are eroding the genetic composition of the virus populations that may have been present in pig herds since their domestication. 相似文献
6.
Nordlund E Aura AM Mattila I Kössö T Rouau X Poutanen K 《Journal of agricultural and food chemistry》2012,60(33):8134-8145
Rye bran and aleurone, wheat bran and aleurone, and oat bran and cell wall concentrate were compared in their in vitro gut fermentation patterns of individual phenolic acids and short-chain fatty acids, preceded by enzymatic in vitro digestion mimicking small intestinal events. The formation of phenolic metabolites was the most pronounced from the wheat aleurone fraction. Phenylpropionic acids, presumably derived from ferulic acid (FA), were the major phenyl metabolites formed from all bran preparations. The processed rye, wheat, and oat bran fractions contained more water-extractable dietary fiber (DF) and had smaller particle sizes and were thus more easily fermentable than the corresponding brans. Rye aleurone and bran had the highest fermentation rate and extent probably due to high fructan and water-extractable arabinoxylan content. Oat samples also had a high content of water-extractable DF, β-glucan, but their fermentation rate was lower. Enzymatic digestion prior to in vitro colon fermentation changed the structure of oat cell walls as visualized by microscopy and increased the particle size, which is suggested to have retarded the fermentability of oat samples. Wheat bran was the most slowly fermentable among the studied samples, presumably due to the high proportion of water-unextractable DF. The in vitro digestion reduced the fructan content of wheat samples, thus also decreasing their fermentability. Among the studied short-chain fatty acids, acetate dominated the profiles. The highest and lowest production of propionate was from the oat and wheat samples, respectively. Interestingly, wheat aleurone generated similar amounts of butyrate as the rye fractions even without rapid gas production. 相似文献
7.
Ukonmaanaho Liisa Starr Michael Ruoho-Airola Tuija 《Water, air, and soil pollution》1998,105(1-2):353-363
Temporal trends in sulfate, base cation (Ca2+ + Mg2+ + K+), and H+ ion concentrations in bulk precipitation and throughfall samples collected over a seven year period (1989-95) in four forested catchments in Finland are presented. The catchments are in remote locations and span the boreal zone (61-69 °N). The stands represent old, undisturbed forests, and are composed of varying proportions of Scots pine, Norway spruce and deciduous species (mainly Betula spp.). Monthly SO4 2- and H+ ion concentrations in bulk precipitation averaged over the study period and catchments were: 18.7 µmol L-1 and 32.3 µmol L-1. The corresponding values for throughfall were: 37.4 µmol L-1 and 32.4 µmol L-1. Sulfate and H+ ion concentrations in bulk precipitation and throughfall both showed negative linear trends, which were significant (p < 0.05) for the three southernmost catchments. Concentrations and trend slope decreased northwards (e.g., bulk precipitation SO4 2- slope estimates: -1.6 to -1.0 µmol L-1 yr-1). The decline was greater for throughfall than for bulk precipitation, indicating a proportionally greater reduction in dry deposition than wet. The sum of base cation concentrations averaged 12.1 µmol(+) L-1 in bulk precipitation and 83.1 µmol(+) L-1 in throughfall. There were no significant trends in the sum of base cations (p > 0.05). It is concluded that the reported reduction in S emissions over the study period has resulted in a significant reduction in the acidity and SO4 2- concentration of bulk precipitation, and this reduction has has been reflected in throughfall concentrations. The greatest reduction has taken place in the southern part of the country. 相似文献
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9.
Martin Forsius Sirpa Kleemola Michael Starr Tuija Ruoho-Airola 《Water, air, and soil pollution》1995,79(1-4):19-38
Ion mass and H+ budgets were calculated for three pristine forested catchments using bulk deposition, throughfall and runoff data. The catchments have different soil and forest type characteristics. A forest canopy filtering factor for each catchment was estimated for base cations, H+, Cl? and SO 4 2? by taking into account the specific filtering abilities of different stands based on the throughfall quality and the distribution of forest types. Output fluxes from the catchments were calculated from the quality and quantity of the runoff water. Deposition, weathering, ion exchange, retention and biological accumulation processes were taken into account to calculate catchment H+ budgets, and the ratio between external (anthropogenic) and internal H+ sources. In general, output exceeded input for Na+, K+, Ca2+, Mg2+, HCO 3 ? (if present) and A? (organic anions), whereas retention was observed in the case of H+, NH 4 + , NO 3 ? and SO 4 2? . The range in the annual input of H+ was 22.8–26.3 meq m?2 yr?1, and in the annual output, 0.3–3.9 meq m?2 yr?1. Compared with some forested sites located in high acid deposition areas in southern Scandinavia, Scotland and Canada, the catchments receive rather moderate loads of acidic deposition. The consumption of H+ was dominated by base cation exchange plus weathering reactions (41–79 %), and by the retention of SO 4 2? (17–49 %). The maximum net retention of SO 4 2? was 87% in the HietajÄrvi 2 catchment, having the highest proportion of peatlands. Nitrogen transformations played a rather minor role in the H+ budgets. The ratio between external and internal H+ sources (excluding net base cation uptake by forests) varied between 0.74 and 2.62, depending on catchment characteristics and acidic deposition loads. The impact of the acidic deposition was most evident for the southern Valkeakotinen catchment, where the anthropogenic acidification has been documented also by palaeolimnological methods. 相似文献
10.
Lang C Söllner H Barz A Ladinig A Langhoff R Weissenböck H Kekarainen T Segalés J Ritzmann M 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(3-4):142-147
In the present retrospective study, serum samples from a total of 253 pigs of different age groups from 83 farms collected in the year 2008 were included.The sera were analysed for the presence of torque teno virus (TTV) genogroups 1 and 2. Furthermore, the correlation between TTV and PCV-2 was investigated. 62.1% of the pigs were positive for TTV1 and/or TTV2 by PCR. 21.7% of the samples were positive for TTV1 and TTV2, 16.2% only for TTV1 and 23.3% only for TTV2. In 80.7% of the investigated farms at least one animal was TTV positive. In the growing and fattening period significantly more pigs were positive for TTV than in other age classes. A positive association was found between TTV1 and IgM against PCV-2, between TTV2 and PCV-2 results by in situ hybridisation (ISH) as well as TTV1 and TTV2 and PCV-2 results by qPCR. A significant correlation could also be seen between the diagnosis,porcine respiratory disease complex (PRDC)" and the detection of TTV, whereas there was none to the diagnosis "porcine dermatitis and nephropathy syndrome (PDNS)". In the present study, TTV was detected in Austria for the first time. 相似文献