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2. Chlorophyll fluorescence parameters characterizing the development of two cacao genotypes infected by witches' broom
- Creator:
- Santos, I. C. F., de Almeida, A.-A. F., and Valle, R. R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Crinipellis perniciosa, genotypes, hybrids, leaf development, pathogens, photosystems 1 and 2, quantum yield, and Theobroma cacao
- Language:
- Multiple languages
- Description:
- Greenhouse-grown susceptible 20-d-old seedlings of Theobroma cacao genotypes Catongo and tolerant genotype SCA6xCatongo were inoculated with a mixture of isolates of Crinipellis perniciosa, the causal agent of witches' broom. The characteristics of chlorophyll a fluorescence emission were monitored during leaf ontogeny using a portable system PAM-2000. In both inoculated and non-inoculated genotypes, significant differences were found for the effective quantum yield values of photosystem (PS) 2 (ΔF/Fm') at the B (7 to 14-d-old), D (21 to 30-d-old), and E (>30-d-old) stages of leaf development, and in quantum yield of the non-cyclic photosynthetic electron transport between PS2 and PS1 [qp(Fv/Fm)] and quencher efficiency [(Fm-Ft)/F0] at the B, C (15 to 20-d-old) and D stages. Intergenotypic differences were found only for the [qp(Fv/Fm)] and [(Fm-Ft)/F0] values at the E stage, and for fluorescence quenching (Fm-Ft) at the B and E stages. Highly significant inter- and intragenotype relationships were found between the rate of photosynthetic electron transport to PS2 (Amax) and maximum fluorescence during actinic irradiation (Fm'). Also, each of the highly significant relationships between (Fm-Ft) and Amax, [(Fm-Ft)/F0] and ΔF/Fm', and between [(Fm-Ft)/F0] and Amax were represented by a general model, independent of treatments. Therefore, alterations in energy distribution in the radiant energy collector complex interior of PS2 and reduction in absorption of photosynthetically active radiation were observed in the infected plants, mainly in the hybrid at the C stage. Also, variations were found in the noncyclic photosynthetic electron transport at the B and C stages in the infected Catongo. and I. C. F. Santos, A.-A. F. de Almeida, R. R. Valle.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Ještě k pravopisným polemikám v 1. polovině 19. století
- Creator:
- Tešnar, Hynek
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Notes to optimization of solar engine
- Creator:
- Stojan, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- endoreversible thermodynamics, heat engine, solar collector, solar energy, and optimization
- Language:
- English
- Description:
- Solar engine is discussed as integration of solar collector with linear heat loss and Curzon-Ahlborn engine is considered. This simple endoreversible model is used to discuss some applications of results of endoreversible heat engine in the field of solar engine. Optimum operating temperature of the solar collector and relevant maximum overall efficiency of solar engine is calculated, the results being compared with those by the models where Carnot and Curzon-Ahlborn efficiences were used. Conclusions obtained for endoreversible model are used for simple optimal design of solar engine. The size of heat engine for a given solar collector is optimized. The investment costs of solar collector and heat engine per unit of output power are used as optimization criterion. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Review of Myxosporea of importance in salmonid fisheries and aquaculture in British Columbia
- Creator:
- Kent, M.L., Margolis, L., Whitaker, D.J., Hoskins, G.E., and McDonald, T.E.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Myxosporea, salmonids, fisheries, and fish pathology
- Language:
- English
- Description:
- everal myxosporean parasites are of importance in fisheries and aquaculture in British Columbia. The PKX organism and Ceratomyxa shasta Noble, 1950 cause disease and mortality, Kudoa thyrsiles (Gilchrist, 1924) and Henneguya salminicola Ward, 1919 are of importance because they infect somatic muscle, cause unsightly cysts and soft flesh, and thus reduce the market value of the fish. Myxobolus arcticus Pugachev et Khokhlov, 1979, an apparently non-pathogenic species, along with H. salminicola, is used as a biological tag in fishery management. Myxobolus arcticus has also been used in our laboratory as a model for the study of myxosporean life cycles. Other myxosporeans that have been found in salmonids in British Columbia include Myxobolus squamalis (Iverson, 1954), Myxobolus insidiosus Wyatt et Pratt, 1963, Myxidium truitae Léger, 1930, Myxidium salvelini Shuhnan et Konovalov, 1966, Chloromyxum sp., ľarvicapsula sp., and Sphaerospora sp.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public