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71.
Tadeusz Caliński Stanisław Czajka Zygmunt Kaczmarek Paweł Krajewski Wiesław Pilarczyk 《Journal of Agricultural, Biological & Environmental Statistics》2009,14(2):224-241
This article describes procedures for studying parameters connected with the genotype-by-environment interactions appearing
in a mixed model derived from the randomization principle. It considers estimation of these parameters and of their meaningful
functions. A test for the overall no-interaction hypothesis is described, and relevant tests for some implied hypotheses concerning
individual parametric functions are considered. Useful data transformations are proposed that allow the graphic presentation
of interesting features of the genotype-by-environment interactions. The theoretical considerations are illustrated by an
analysis of the results of a series of trials with pea varieties. 相似文献
72.
Marcin K. Dyderski Anna Gazda Mariusz Hachułka Paweł Horodecki Izabela L. Kałucka Jacek Kamczyc Marek Malicki Remigiusz Pielech Michał Smoczyk Maciej Skorupski Sylwia Wierzcholska Andrzej M. Jagodziński 《Annals of Forest Science》2018,75(4):91
? Key message
Natural regeneration of P. abies (L.) H. Karst. may reach high densities in lower mountain elevations. The highest densities were found in sites with moderate light availability, with low pH, and not near the riverbank. However, age-height classes differed in the predicted magnitude of response, but were consistent in response directions. Mosses and understory species typical of coniferous forests were positively correlated with regeneration density.? Context
Norway spruce Picea abies (L.) H. Karst. in Central Europe is at risk under climate change scenarios, particularly in mountain regions. Little is known about the impact of environmental factors on the natural regeneration of P. abies in low-elevation mountain forests.? Aims
We aimed to assess impacts of distance from the riverbank, soil pH, and light availability on natural P. abies regeneration. We hypothesized that (1) natural P. abies regeneration would depend on light availability and soil pH and (2) there are understory plant species which may indicate the microsites suitable for natural regeneration of P. abies.? Methods
The study was conducted in the Sto?owe Mountains National Park (SW Poland, 600–800 m a.s.l.). We established 160 study plots (25 m2) for natural regeneration, light availability, soil pH, and understory vegetation assessment.? Results
The highest densities of natural regeneration of P. abies were observed in sites with moderate light availability (0.1–0.2 of open sky) and low pH (3.5–4.5), and located relatively far from the riverbank. Cover of 22 understory plant species were correlated with natural P. abies regeneration densities, mostly positively.? Conclusion
Different stages of natural regeneration of P. abies revealed different regeneration niches. Most understory plant species (bryophytes and herbs typical of coniferous forests) do not compete with natural regeneration of P. abies.73.
Rafał Podlaski 《Annals of Forest Science》2018,75(4):99
Key message
From 1973 to 1991, Polish SO 2 emissions above 3250 Gg/year resulted in a decline of fir Abies alba Mill. After stresses connected with these emissions, five main diameter at breast height (DBH) structural types were described. This type of heterogeneous forest structure is supposed to increase forest resistance and resilience to abiotic, biotic and anthropogenic disturbances.Context
The analyses of forest structure are important under the current scenario of global change, since heterogeneous structures allow for better responses to disturbances. Forests with more complex structures should present greater vitality.Aims
The main hypotheses were as follows: (1) the temporal changes of atmospheric SO2 emissions caused (a) the abrupt changes in the tree DBH radial increment and (b) the death of fir trees; and (2) atmospheric SO2 emissions and related fir decline and recovery processes ultimately result in the development of stands characterised by diverse DBH structures.Methods
Radial growth trends of 49 and 215 fir trees in the older and younger generations, respectively, and 85 dead fir trees were evaluated. Using data collected in 32 stands, the DBH structural types were identified, and the shapes of these types were illustrated.Results
The structural diversification of forest patches may influence forest resistance and resilience to disturbances; five main structural types were identified: ML1 and ML2 represent DBH distributions of multi-layered stands, and OS, TS1 and TS2 represent DBH distributions of one- and two-storied stands.Conclusion
Structural diversity of forests was a response to SO2 emissions; fir trees had the ability to increase their radial growth, although there were still high SO2 emissions.74.
Jakub Borkowski Dorota Dobrowolska Wojciech Dąbrowski Rafał Banul Dariusz Załuski 《European Journal of Forest Research》2017,136(5-6):787-800
There is little knowledge how ungulate pressure on forest regeneration may be mitigated by silvicultural methods. The knowledge is especially needed for artificially regenerated, deciduous tree species. We studied factors affecting browsing incidence by deer in the Pisz Forest District in Poland, an area where 10,000 ha of forest was damaged by a 2002 hurricane. In 2006, we established three experimental plots (in total, 22.6 ha), in which the main species was Scots pine (Pinus sylvestris) admixed with pedunculate oak (Quercus robur). The data on browsing were collected in 2008–2015. In general, oak browsing incidence was unrelated to oak planting density. On a plantation scale, it was significantly affected by the pine age. Although in each variant all the oaks were browsed for four consecutive years (2009–2012), in 2013 browsing incidence began to decrease. When the pines grew higher and formed a physical barrier, it was harder for deer—roe deer (Capreolus capreolus), red deer (Cervus elaphus) and moose (Alces alces)—to move through and locate the oaks. Moreover, within plantations, oak browsing incidence was higher in the patches with shorter pines. Browsing of individual saplings or small groups of saplings was also negatively affected by the height of neighbouring pine saplings. Oak density influenced deer selectivity depending on the tree height. In a low oak tree density, browsing incidence was unrelated to oak height, while in higher tree density, deer selected oaks of the height between 40 and 100 cm. We postulate that deciduous admixture in a coniferous (unattractive) stand can be planted with a few year delay. Older coniferous trees should impede locating of attractive tree species by deer and the browsing incidence. 相似文献
75.
Herbicidal pyridyl derivatives of aminomethylene-bisphosphonic acid inhibit plant glutamine synthetase 总被引:3,自引:0,他引:3
Obojska A Berlicki L Kafarski P Lejczak B Chicca M Forlani G 《Journal of agricultural and food chemistry》2004,52(11):3337-3344
A series of aminomethylene-bisphosphonic acid derivatives, previously synthesized and shown to be endowed with herbicidal properties, were evaluated as potential inhibitors of plant glutamine synthetase. The cytosolic form of the enzyme was partially purified from rice cultured cells and assayed in the presence of millimolar concentrations of the compounds by means of three different assay methods, respectively measuring the hemibiosynthetic, the transferase, and the full biosynthetic reactions. Several compounds were found to exert a remarkable inhibition, with I(50) values similar to those obtained under the same conditions with a well-established inhibitor of glutamine synthetase, the herbicide phosphinothricin. Contrary to the reference compound, enzyme kinetics accounted for a reversible inhibition mechanism. The biological activity of the most active derivatives was further characterized by measuring free glutamine levels in cell suspension rice cultures following treatment with the inhibitors. Results confirmed their ability to interfere in vivo with nitrogen metabolism. A preliminary analysis of structure-activity relationship allowed it to be hypothesized that steric rather than electronic factors are responsible for the inhibitory potential of these compounds. 相似文献
76.
Izabela Janus Małgorzata Kandefer-Gola Rafał Ciaputa Agnieszka Noszczyk-Nowak Urszula Pasławska Massimiliano Tursi Marcin Nowak 《Irish veterinary journal》2015,69(1):18
Background
Dilated cardiomyopathy (DCM) and myxomatous mitral valve disease (MMVD) are the most common diseases noted in dogs. Although their pathogenesis varies, both include a significant enlargement of the left atrium.The study was carried out on left atrial specimens obtained from 56 dogs, including those from 34 dogs with clinically diagnosed MMVD, 15 dogs with DCM and 7 dogs without heart disease (control group). Dogs in the MMVD and the DCM groups presented with left atrial enlargement and stage D heart failure. The specimens underwent immunohistochemical examination using desmin, vimentin, periostin and caspase-3 antibodies.Results
There were alterations in the expression of the studied proteins in the study groups compared to the control group. The changes included: irregularity of desmin cross-striation and desmosomes, a higher amount of vimentin-positive cells, a change in the periostin expression pattern from cytoplasmic to extracellular, and a lower expression of caspase-3. The alterations were more pronounced in the DCM group than in the MMVD group.Conclusions
During heart failure, the pattern of desmin, vimentin, periostin and caspase-3 expression alters in the left atrium, regardless of the cause. The changes are more pronounced in dogs with DCM than in dogs with MMVD and similar left atrial enlargement, suggesting that volume overload may not be the only cause of myocardial changes in DCM.77.
78.
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
79.
Journal of Plant Diseases and Protection - Influence of moisture on maturation rate of the airborne Venturia inaequalis (Cooke) Wint. ascospores was numerically examined using field data collected... 相似文献
80.