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61.
Summary The possibility of producing agronomically-useful somaclones via organogenesis and somatic embryogenesis from callus cultures of pea (Pisum sativum L.) was studied. Organogenic calli were induced from immature leaflets on MSB medium with NAA and BAP. Embryogenic calli were derived either from immature zygotic embryos (using 2,4-D) or from shoot apices (using picloram) of aseptically-germinated seedlings.The seed progenies (T1 to T3-generation) of primary regenerants were grown in field conditions and their phenotypic variation was evaluated and compared with control, non-tissue culture-derived plant material. In addition, electrophoretic analyses of selected isoenzyme systems and total proteins have been done. The results do not show dramatic changes in qualitative and quantitative traits. The evaluation of at least two future generations (T4, T5) is planned.Abbreviations BAP
6-benzylaminopurine
- IBA
indole-3-butyric acid
- MSB
medium (mineral salts after Murashige & Skoog, 1962, vitamins after Gamborg et al., 1968)
- NAA
-naphthalene-acetic acid, picloram-4-amino-3,5,6-trichloro picolinic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- ORG
organogenesis
- SE
somatic embryogenesis 相似文献
62.
At the "Small Animal Clinic of the University of Veterinary Science" in Brno during four years 442 sick and 178 clinically normal cats were examined in regard to incidence and diagnosis of toxoplasmosis. Using the Sabin-Feldman reaction, antibodies against T.gondii were found in 40.3% of the cats (titer 4-128), whereas by means of complement fixation reaction and microprecipitation in agar gel, antibodies were found in 23.2% (titer 5-80) and 17.1% of the cats, respectively. Eight cats (1.3%) excreted T.gondii oocysts. The number of animals having specific antibodies increased statistically significant with age (P less than 0.01) and with particular hunting habits: it was higher in cats which were usually catching small rodents (P less than 0.01). A lower toxoplasmosis incidence was observed in indoor-cats (P less than 0.005) and in cats fed with boiled food only (P less than 0.005). In 35% of the cats showing no clinical symptoms of toxoplasmosis, there were found antibodies against T.gondii. Comparison of clinically normal and sick cats revealed that antibodies against T.gondii occurred significantly more often in cats with enlarged lymph nodes (P less than 0.01), with a disease of the digestive tract (P less than 0.01), of the liver (P less than 0.01), and of the nervous system (P less than 0.01). Several recommendations for diagnosis and prophylaxis of toxoplasmosis in cats are given. 相似文献
63.
Miroslav Zorić Sreten Terzić Vladimir Sikora Milka Brdar-Jokanović Dimitar Vassilev 《Euphytica》2017,213(1):23
Tuber yield, together with tuber number and size are the basic agronomic and breeding traits in Jerusalem artichoke and can be significantly affected by environmental factors. We report the results of a long term trial on the performance of 20 Jerusalem artichoke cultivars. The random model for means with restricted maximum likelihood (REML) procedure was used to estimate the overall effects of the genotype, environment and genotype by environment interaction on traits. The partial least square regression (PLSR) model was used for modeling genotype by environment interaction variance components with a set of available correlated environmental variables. The REML variance component estimates model revealed that tuber number and yield are more dependent on GE interaction which allowed identification of best genotypes for specific environments. The PLSR model revealed that the most important climatic variables for optimal emergence, canopy development, high tuber number and yield are adequate soil and air temperatures in April. For larger tuber mass, precipitation variables and even distribution of rainfall were the most important factor, together with soil and air temperature in June when tuber growth is initiated. The knowledge obtained in this study is valuable for the identification and understanding of key environmental factors that contribute to the performance of Jerusalem artichoke. 相似文献
64.
Jitka Hamáčková Andrea Lepičová Miroslav Prokeš Pavel Lepič Pavel Kozák Tomáš Policar Leon Andrzej Stanny 《Aquaculture International》2007,15(3-4):255-265
The ide Leuciscus idus (Linnaeus 1758) belongs to autochthonous, less frequent and vulnerable fish species in the frame of ichthyofauna of the Czech
Republic. It was the reason for testing the possibility of captive breeding and production of fry in a controlled environment.
The goal of this paper was to find the optimal transfer time of ide larvae from live food (Artemia salina nauplii) to dry starter feed providing good survival and growth. At the end of the experiment, high values of cumulative
survival (in percentages) and individual weight (in milligrammes) were found for ide fry in groups D (90.6%, 178.6 mg; 15 days
A.
salina + 10 days starter feed), A (89.9%, 169.9 mg; A. salina only) and C (88.6%, 160.4 mg; 10 days A. salina + 15 days starter feed). Significantly lower values of the given parameters were found in group B (57.1%, 92.6 mg; 5 days
A. salina + 20 days starter feed), and the lowest ones were in group E (29.8%, 75.6 mg; starter feed only). Mean values of the level
of ontogenesis at the end of the experiment in fry of A–E groups were analogous to length and weight growth. Groups D, C and
A consisted of juveniles only (J1, J2), and groups B and E consisted of larvae and juveniles (L4, L5, L6, J1, J2). Condition
and production parameters [Fulton’s coefficient of condition (FWC), total length (TL), weight (w), specific growth rate (SGR),
food conversion ratio (FCR), cumulative survival] and relationships between basic lengths TL, fork length (FL) and standard
length (SL) were evaluated. 相似文献
65.
J Svoboda 《Veterinární medicína》1992,37(9-10):543-547
The extensity of digestive tract infection with different parasites in domestic fowl kept on large and small farms was diagnosed in individual months of the years 1986-1989. The obtained results were confronted with the values of average monthly temperatures and rainfall sums in individual months of the above-mentioned period. The numbers of birds examined in individual months of the years 1986-1989 were as follows: 105 to 234 from large farms and 32 to 112 from small farms. The numbers of examined chicks from small farms were lowest in winter, and on the other hand highest in summer. The numbers of examined fowl from large farms varied from month to month. Particularly Coccidia (average extensity 12.1%), scarcely Heterakis gallinae (0.2%) and Capillaria spp. (0.1%) were detected in birds kept on a large scale. The occurrence of Coccidia fluctuated from 5% in birds dissected in May, July and November to 22% in birds dissected in August. H. gallinae and Capillaria spp. occurred rarely, namely in the second half of the year after warm and rainy periods (Figs. 1 and 2). The occurrence of gastrointestinal parasites in domestic fowl kept on small farms is variable within the year while the change begins in summer and culminates in autumn after warm and rainy months. Only following the sporulation of larger numbers of oocysts, or the maturation of larger numbers of eggs or cysticercoids their pathogenicity can play a key role while their concentrations in the environment are increasing. Hence parasitoses begin to appear after the rise of temperatures and rainfall.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
66.
Nagy A Machova J Hornickova J Tomci M Nagl I Horyna B Holko I 《Veterinary microbiology》2007,120(1-2):9-16
In order to determine the actual prevalence of avian influenza viruses (AIV) in wild birds in the Czech Republic extensive surveillance was carried out between January and April 2006. A total of 2101 samples representing 61 bird species were examined for the presence of influenza A by using PCR, sequencing and cultivation on chicken embryos. AIV subtype H5N1 was detected in 12 Mute swans (Cygnus olor). The viruses were determined as HPAI (highly pathogenic avian influenza) and the hemagglutinin sequence was closely similar to A/mallard/Italy/835/06 and A/turkey/Turkey/1194/05. Following the first H5N1 case, about 300 wild birds representing 33 species were collected from the outbreak region and tested for the presence of AIV without any positive result. This is the first report of highly pathogenic avian influenza subtype H5N1 in the Czech Republic. The potential role of swan as an effective vector of avian influenza virus is also discussed. 相似文献
67.
Pikula J Adam V Bandouchova H Beklova M Horakova J Horakova H Kizek R Krizkova S Skocovska B Supalkova V Svoboda M Tremi F Vitula F 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(4):361-363
Background: Many causes of mortality in the European brown hare, such as bacterial and viral infections, anticoagulant poisoning, and trauma, may result in hemorrhage. There are, however, no reference values concerning blood clotting in this species. Objectives: The aim of this study was to determine reference values for blood coagulation times and related parameters in healthy European brown hares. Methods: Blood samples from 30 clinically healthy adult hares (15 males and 15 females) were obtained. Hares were physically restrained for blood collection from the cephalic vein into tubes containing citrate and EDTA. Results: Mean ± SD were obtained for thrombin time (TT) (13.97 ± 1.37 seconds), prothrombin time (PT) (13.32 ± 2.15 seconds), activated partial thromboplastin time (APTT) (16.73 ± 1.86 seconds), fibrinogen concentration (2.98 ± 1.06 g/L), and platelet count (355.28 ± 128.73 × 109 /L). Conclusions: Reference values for blood coagulation times and other parameters associated with blood clotting will be useful in the laboratory evaluation of hemorrhage in the European brown hare. 相似文献
68.
Giorgio Vacchiano R. Justin Derose John D. Shaw Miroslav Svoboda Renzo Motta 《European Journal of Forest Research》2013,132(3):535-549
Norway spruce is one of the most important conifer tree species in Europe, paramount for timber provision, habitat, recreation, and protection of mountain roads and settlements from natural hazards. Although natural Norway spruce forests exhibit diverse structures, even-aged stands can arise after disturbance or as the result of common silvicultural practice, including off-site afforestation. Many even-aged Norway spruce forests face issues such as senescence, insufficient regeneration, mechanical stability, sensitivity to biotic disturbances, and restoration. We propose the use of Density Management Diagrams (DMD), stand-scale graphical models designed to project growth and yield of even-aged forests, as a heuristic tool for assessing the structure and development of even-aged Norway spruce stands. DMDs are predicated on basic tree allometry and the assumption that self-thinning occurs predictably in forest stands. We designed a DMD for Norway spruce in temperate Europe based on wide-ranging forest inventory data. Quantitative relationships between tree- and stand-level variables that describe resistance to selected natural disturbances were superimposed on the DMD. These susceptibility zones were used to demonstrate assessment and possible management actions related to, for example, windfirmness and effectiveness of the protective function against rockfall or avalanches. The Norway spruce DMD provides forest managers and silviculturists a simple, easy-to-use, tool for evaluating stand dynamics and scheduling needed density management actions. 相似文献
69.
Libor Mrnka Michal Kuchár Zuzana Cieslarová Pavel Matějka Jiřina Száková Pavel Tlustoš Miroslav Vosátka 《Water, air, and soil pollution》2012,223(1):399-410
There is increasing interest in poplars and willows due to their biomass production and phytoremediation potential. They host
two major types of mycorrhizal fungi that can substantially modulate the physiology of their hosts. In this study, the effects
of endo- and ectomycorrhizal fungi on growth, physiological parameters, and heavy metals accumulation were studied in a pot
experiment using Salix alba L. and Populus nigra L. The mycorrhizal fungi were inoculated separately and in combination to a soil substrate polluted by a mixture of heavy
metals (mainly Cd, Pb, and Zn). Tree species differed in their mycorrhizal affinities, with poplar being colonized predominantly
by Glomus intraradices and willow by Hebeloma mesophaeum. H. mesophaeum increased willow height and biomass, while G. intraradices decreased poplar height. The photosynthetic rate remained unchanged, and only minor changes were observed in the relative
composition of photosynthetic pigments. Poplar photosynthetic rates and levels of photosynthetic pigments declined, while
the epicuticular waxes in leaves increased toward the end of the experiment, irrespective of the inoculation. H. mesophaeum strongly reduced the accumulation of Cd and Fe in willow and poplar shoots, respectively. Our results support the use of
selected mycorrhizal strains to tune phytoremediation outcomes in their plant hosts. 相似文献
70.
Ludmila Machů Dušan Samek Jan Hrabě Miroslav Fišera 《Journal Of Aquatic Food Product Technology》2013,22(5):423-435
Digestibility is an important factor in determining the level of nutritive factors utilization. Determination of in vitro digestibility in a Daisy incubator and assessment of protein digestibility using Kjeldahl method of algal food products after pepsin, pancreatin, and combined hydrolysis of both enzymes was described. The influence of different hydrolysis times on algal digestibility was investigated in brown seaweeds, red seaweeds, and green alga. The highest digestibility values were generally determined in red seaweeds after 24 h of combined hydrolysis by pepsin and pancreatin. Direct dependence between digestion time and digestion efficiency was verified and statistically proven. 相似文献