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2301. Leaf area, chlorophyll content and biomass of tomato plants and their heterotic hybrids under in vitro culture

Creator:
Titok, V.V., Lemesh, V.A., Rusinova, O.V., and Podlisskikh, V.L.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Dry matter, leaf area, leaf area ratio (LAR), specific leaf mass (SLM), and chlorophyll (Chi) a and b contents in different cultivars, lines and Fj hybrids of tomato plants (Lycorpersicon esculentum Mill.) were studied under constant in vitro conditions. Plant biomass and Chi content heterosis were observed in all breeding combinations regardless of genotypic features of initial forms. No differences in leaf area were found among cultivars, lines and Fj hybrids. High significant correlations were established among dry matter production, LAR and SLM values.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2302. Leaf phosphate status and photosynthesis in vivo: changes in sugar phosphates, adenylates and nicotinamide nucleotides during photosynthetic induction in sugar beet

Creator:
Madhusudana Rao, I. and Terry, N.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Sugar beets (Beta vulgaris L. cv. F58-554H1) were cultured hydroponically in growth chambers. Leaf orthophosphate levels were varied nutritionally. The effect of decreased leaf phosphate (low-P) status was determined on the rate of photosynthesis (PN) and on pool sizes of leaf ribulose-l,5-bisphosphate (RuBP), 3-phosphoglycerate (PGA), triose phosphate (triose-P), fructose-1,6-bisphosphate (FBP), fructose-6-phosphate (F6P), glucose-6-phosphate (G6P), adenylates and nicotinamide nucleotides during photosynthetic induction (measured at 0, 1.5, 5 and 30 min from irradiation). p N reached 50 % of its final value in 4 min in control leaves and 10 min in low-P leaves. Hence the increase in the length of induction period in low-P leaves was most likely due to a slow build-up in RuBP: ATP, NADPH, PGA, and FBP all reached high levels in 5 min at which time RuBP was half and PN 16 % of their eventual values at 30 min. The slow-build-up of RuBP did not appear to be due to insufficient ATP and NADPH for the conversion of PGA to triose-P; rather, low-P seemed to limit photosynthetic induction somewhere in the sequence of reactions between triose-P and RuBP formation.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2303. Leaf photosynthesis and chlorophyll fluorescence in a chlorophyll-deficient soybean mutant

Creator:
Xu, D. Q., Chen, X. M., Zhang, L. X., Wang, R. F., and Hesketh, J. D.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
A comparative study of chlorophyll (Chl) fluorescence characteristics was made between a soybean [Glycine max (L.) Merr.] Chl-deficient mutant (light green leaf, LG, Eji^ii), and a nearly isogenic Chl normál biotype (dark green leaf, DG, EnEn) of cultivar Clark, LG had a lower light-saturated net photosynthetic rate (/^n), compared with DG at early stages of growth (before pod filling), but the difference in Ejsi between LG and DG became smaller at later stages of growth. The lower of LG may result from lower Chl content (Chl a and b), lower carboxylation efficiency, and lower photochemical efficiency of photosystem 2. Both LG and DG grown at low iradiance [about 200-300 pmol(photon) m'^ s"’] in a growth cabinet had similar photochemical effíciencies. However, the efficiency was lower in LG than in DG grown in field sunlight in mid summer, especially during the aftemoon on clear days, indicating that LG is more sensitive to photoinhibition.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2304. Leaf photosynthesis is resistant to a mild drought stress

Creator:
Cornic, G., Ghashghaie, J., Genty, B., and Briantais, J.-M.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
When a terrestňal plant is subjected to a mild drought stress, the leaf net CO2 uptake declines as a result of the stomatal closure. In contrast to previous beliefs the photosynthetic apparatus is vety resistant to dehydration. Particularly the relations between photochemistry, its regulation and leaf CO2 assimilation (f) are identical when F is changed either by increasing leaf water deficit or by decreasing the ambient CO2 concentration. When the stomata close in a leaf under water deficit the CO2 concentration within the leaf declines. As a result photorespiration is favoured, the photochemical yield of open photosystem 2 (PS 2) centres and the activity of some enzymes dechne (sucrose-phosphate synthase, nitráte reductase). The dechne of photochemical yield of PS 2 is consequential to an increase in thermal dissipation of the excitons trapped by PS 2 units. The dechne in CO2 concentration occurring in a desiccating leaf may trigger an integrated response of leaf metabohsm which still remains to be explored.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2305. Leaf photosynthetic nitrogen-use efficiency of C3 and C4 Cyperus species

Creator:
Li, Meirong
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
A comparison of photosynthetic nitrogen (N) use efficiency between C3 and C4 species within the genus Cyperus was made at a range of available nitráte levels. Net photosynthetic rates (P^) of both types increased with N content but CO2 assimilation on a leaf area basis was consistently higher in C4 species in comparison to the C3 species. C4 plants had a higher photosynthetic N use efficiency than C3 plants, and achieved higher Pn at lower N and protein levels. The higher leaf photosynthetic N use efficiency (PNUE) in C4 plants is due to their high raťher than low N and protein contents. Because C^ leaves contain less N than C3 leaves for a given Py^, PNUE is significantly higher in C4 than C3 plants. Nitrogen supply had highly significant effect on the leaf N concentration, but had no significant influence on the CO2 compensation concentration. Carboxylation efficiency was significantly higher in C4 leaves than C3 leaves of Cyperus species, due to the CO2 concentrating mechanism of C4 photosynthesis.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2306. Leaf senescence patterns and photosynthesis in four leaf flushes of two deciduous oak (Quercus) species

Creator:
Tobiáš, D.J., Ikemoto, A., and Nishimura, T.
Format:
print
Type:
model:internalpart and TEXT
Subject:
chlorophyll, leaf area, leaf duration, leaf number, net photosynthetic rate, Quercus acutissima, and Quercus serrata
Language:
Multiple languages
Description:
Changes in chlorophyll (Chl) a+b and a/b, senescence patterns during Chl loss and changes in net photosynthetic rate (P^) of four leaf flushes in Quercus acutissima and Q. serrata were studied. Emergent current-year leaves were classified according to the order of shoot growth flushes (first to fourth flush groups). Senescence patterns showed that leaf fall started from the leaf cohorts of the first flush group (the "oldest" leaf cohorts) which cuhninated upwards to the fourth leaf flush group (the "yoímgest" leaf cohorts). Senescence during Chl loss was accompanied by a decline in Pf^. A strong influence by the leaf flushing phenomenon on senescence was found which limited leaf bearing period and duration of Having large total leaf area and moderately long duration, tiie third and second leaf flush groups reflected the highest photosynthetic potential. This may be a positive attribute since the duration by which these plants maximize the use of its assimilatory organs is an important factor for their carbon fixation.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2307. Lectin-like sequences in genome of Borrelia burgdorferi

Creator:
Rudenko, Natalia, Golovchenko, Maryna, and Grubhoffer, Libor
Format:
print
Type:
model:internalpart and TEXT
Subject:
Borrelia burgdorferi, hemagglutination, genomic library, recombinant, and lectin
Language:
English
Description:
Using degenerative primers designed on the basis of known sequences of lectin genes from different sources a fragment of genomic DNA of Borrelia burgdorferi ( strain B31) that contained a lectin-like sequence was isolated, cloned and sequenced. The presence of an open reading frame of 268 amino acids (position 1501-2304 bp) and the computer analysis of the predicted amino acid sequence showed 37% of identity and 75% of homology over region of 25 amino acids with the legume lectin proteins, including erythroagglutinating phytohcmagglutinin (РНЛ-Е) and leucoagglutinating phylohemagglutinin (PHA-L). The further analysis of the predicted amino acid sequence showed the presence of another two domains (positions 198-211 and 215-226 aa) consisting of the characteristic conserved sequence motifs for legume lectin proteins. Hemagglutinating activity was detected in lysate of В burgdorferi (strain B31) spirochete and the affinity to fetuin was determined in a hemagglutination inhibition test. Hemagglutinating activity was also found in a crude lysate of the recombinant clones carrying the fragment of B. burgdorferi genomic DNA. The inhibition of agglutinating activity by fetuin, D-galactosamine and D-mannosamine was determined using the standard procedure of hemagglutination inhibition test with native rabbit red blood cells (RBC).
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2308. Lectins and tick-pathogen interactions: a minireview

Creator:
Grubhoffer, Libor and Jindrák, Libor
Format:
print
Type:
model:internalpart and TEXT
Subject:
Blood sucking arthropod, lectin, agglutinin, glycoconjugates, borrelia, and tick
Language:
English
Description:
Lectins and their glycosylated receptors in a system of the tick-transmitted pathogen are the addressed topics which the minireview is dealing with. They participate in the reciprocal protein-saccharide interactions in the transmission of the causative agents of the tick-borne encephalitis and Lyme borreliosis by the ticks. Functional significance of the tick tissue specific lectins as well the lectins/aggulutinis of the transmitted pathogens in molecular ecology of the tick borne diseases has been shown.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2309. Lectins in snail-trematode immune interactions: a review

Creator:
Horák, Petr and van der Knapp, Wil P. W.
Format:
print
Type:
model:internalpart and TEXT
Subject:
lectin, agglutinin, carbohydrate, trematode, schistosome, snail, immunity, and haemocyte
Language:
English
Description:
Lectins as carbohydrate recognition proteins other than enzymes or immunoglobulins play important roles in living systems, e.g., in celi celi recognition. They are considered to be involved in snail-trematode immune interactions, i.e., in a system where antibodies are lacking and lectins might at least partially substitute immunoglobulin functions. From the snail side, lectins can be located on haemocyte surfaces as receptors for foreignness and they can be found freely in plasma. The latter can function as agglutinins/opsonins helping in the recognition of parasites by haemocytes. They may also link immune cells and pathogens by recognition of surface carbohydrates on both. Lectins of parasite origin could also be involved in snail-trematode interactions. They might function as trematode surface receptors for snail glycoconjugates in parasite masking strategies. Functions other than the involvement in the snail's immune response or the parasite’s evasion strategies might be fulfilled by lectins as well. Among these may be host-finding, penetration, orientation in the host, nutrition. It cannot be omitted that lectin-saccharide reactions represent only a part of the snail-trematode interactions and thus, results obtained from lectin experiments are a rough simplification of the actual, very complicated situation. An array of immune and other reactions comprised of yet unknown bioactive molecules certainly exists in snails and, on the other hand, trematode mechanisms to escape or otherwise interact with these, might be involved at the same time. But we can certainly conclude that a more complete view of the complex snail-trematode interactions also necessitates a more profound knowledge of the identity and functioning of lectins and their ligands, in host and parasite.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2310. Legitimita, angažovanost a vytváření sociálního kapitálu na českém pracovišti v období pozdní transformace

Creator:
Passmore, Ben and Ogrocká, Jana
Format:
print
Type:
model:internalpart and TEXT
Subject:
post-communist transition, organizational culture, social capital, engagement, legitimacy, and Czech Republic
Language:
Czech
Description:
Previous research indicates that Czechs harbor considerable doubt about the honesty of their political and economic system. One response to this perceived dishonesty has been disengagement, to the extent possible, from their work and public life. Disengagement was, both before and after 1989, the potent weapon used by Czechs in their workplaces to covertly make their wishes known on the factory floor. This behavior has proven problematic for the managers of the „new" private enterprises in the country. The tension between management and workers has resulted in the creation of complex interactions which can begin to be understood through an analysis of transactions in social capital. To accomplish this, this paper will examine two relatively successful companies in the Southern Moravian city of Brno during the period preceding E.U. accession. Through field notes, interview and survey data gathered during more than a year of ethnographic fieldwork, this paper will accomplish three objectives. It will analyze the interplay in those companies of discourses of honesty with the twin goals of managerial legitimacy and worker engagement. It will document the process of negotiation which has resulted in the development of a new moral economy on the workfloor and the growth of powerful worker networks within the enterprise. Finally, it will present a theoretical framework to capture the process of social capital creation and expenditure which is the product of these processes.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public