Number of results to display per page
Search Results
392. Cultivar variation in cotton photosynthetic performance under different temperature regimes
- Creator:
- Pettigrew, W. T.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorofyl, bavlna, teplota, chlorophyll, cotton, temperature, fluorescence chlorofylu, kultivary, abiotický stres, mezibuněčná koncentrace CO2, list, výměna plynu, termotolerance, efektivita využívání vody, chlorophyll fluorescence, cultivars, abiotic stress, intercellular CO2 concentration, leaf, gas exchange, maximum quantum yield, thermotolerance, water-use efficiency, 2, and 581
- Language:
- Multiple languages
- Description:
- Cotton (Gossypium hirsutum L.) yields are impacted by overall photosynthetic production. Factors that influence crop photosynthesis are the plants genetic makeup and the environmental conditions. This study investigated cultivar variation in photosynthesis in the field conditions under both ambient and higher temperature. Six diverse cotton cultivars were grown in the field at Stoneville, MS under both an ambient and a high temperature regime during the 2006-2008 growing seasons. Mid-season leaf net photosynthetic rates (PN) and dark-adapted chlorophyll fluorescence variable to maximal ratios (Fv/Fm) were determined on two leaves per plot. Temperature regimes did not have a significant effect on either PN or Fv/Fm. In 2006, however, there was a significant cultivar × temperature interaction for PN caused by PeeDee 3 having a lower PN under the high temperature regime. Other cultivars' PN were not affected by temperature. FM 800BR cultivar consistently had a higher PN across the years of the study. Despite demonstrating a higher leaf Fv/Fm, ST 5599BR exhibited a lower PN than the other cultivars. Although genetic variability was detected in photosynthesis and heat tolerance, the differences found were probably too small and inconsistent to be useful for a breeding program., W. T. Pettigrew., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
393. Cyanide-resistant respiratory pathway is involved in the high-light systemic acquired acclimation of kidney bean
- Creator:
- Feng, H.-Q., Tang, S.-Z., Sun, K., Jia, L.-Y., and Wang, R.-F.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, fazol obecný, photosynthesis, Phaseolus vulgaris, bean leaf, chlorophyll fluorescence, salicylhydroxamic acid, 2, and 581
- Language:
- Multiple languages
- Description:
- After exposing one half of a low light-adapted kidney bean (Phaseolus vulgaris) leaf to high light, parameters of chlorophyll (Chl) a fluorescence, such as PSII operating efficiency, PSII maximum efficiency under light, and photochemical quenching, decreased in the opposite half of the same leaf, whereas the capacity of the cyanide-resistant respiratory pathway significantly increased. When one half of the low light-adapted leaf was exposed to low light, the opposite half pretreated with 1 mM salicylhydroxamic acid (SHAM, an inhibitor of the cyanide-resistant respiratory pathway) did not exhibit significant changes in the Chl fluorescence values compared with the without SHAM pretreatment. However, after exposing one half of the low light-adapted leaf to high light, the opposite half pretreated with 1 mM SHAM showed lower Chl fluorescence values than that without SHAM pretreatment. Our results indicate that partial exposure of the low light-adapted leaf to high light can impose a systemic stress on the PSII photochemistry. The enhanced capacity of the cyanide-resistant respiratory pathway may be involved in the maintenance of the photosynthetic performance in the leaf tissues experiencing high light-induced systemic stress., H.-Q. Feng, S.-Z. Tang, K. Sun, L.-Y. Jia, R.-F. Wang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
394. Cyklus Organická chemie
- Creator:
- Zdeněk Drahota and Ústav makromolekulární chemie (Československá akademie věd)
- Publisher:
- ČSAV. Ústav organické chemie a biochemie
- Format:
- print and v, 205 s.
- Type:
- model:monograph and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, biochemie, 577.1, (048.8), 2, and 577
- Language:
- Czech
- Description:
- Sv. 9, Vybrané kapitoly z biochemie, Z. Drahota ... [et al.]., and Na titulní str. uveden rok vydání 1982
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
395. Cystoidosoma hermaphroditus sp. n., the first representative of the quill mite family Ascouracaridae (Acari: Astigmata: Pterolichoidea) from an owl (Aves: Strigiformes)
- Creator:
- Hernandes, Fabio Akashi and OConnor, Barry M
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- roztoči, parazitický hmyz, sovy, mites, parasitic insects, owls, 2, and 59
- Language:
- English
- Description:
- The mite family Ascouracaridae Gaud et Atyeo, 1976 contains large-sized mites (mostly > 1 mm) which live inside the quills of birds of several orders. To date, no representative of this family has been found associated with the order Strigiformes (owls). In this paper, a new species of this family, Cystoidosoma hermaphroditus sp. n., is described from the tropical screech owl, Megascops choliba (Vieillot) (Aves: Strigiformes) from Brazil. This species is unique in having an external spermaduct, a primary duct and a rudimentary bursa copulatrix present in males. This is the first astigmatan feather mite described from the order Strigiformes in this country. A key to adults of the genus Cystoidosoma Gaud et Atyeo, 1976 of the world is presented., Fabio Akashi Hernandes, Barry M. OConnor., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
396. Cytogenetic characterization of Diachasmimorpha longicaudata (Hymenoptera: Braconidae), a parasitoid wasp used as a biological control agent
- Creator:
- Carabajal Paladino, Leonela, Papeschi, Alba, Lanzavecchia, Silvia, Cladera, Jorge, and Bressa, María José
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Diachasmimorpha longicaudata, karyotype, C-banding, heterochromatin, Ag-NOR, FISH, rDNA, 2, and 59
- Language:
- English
- Description:
- Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a parasitoid wasp widely used in the biological control of fruit flies. In this paper, we present a detailed analysis of the karyotype of this species based on the results of classical and molecular cytogenetic techniques. The cytogenetic analysis confirmed the male and female chromosome numbers previously reported (n = 20, 2n = 40). The entire short arm of most chromosomes is made up of a large constitutive heterochromatic segment. The high heterochromatin content differentiates D. longicaudata from other braconid species. Fluorescence in situ hybridization (FISH) using autologous 18S rDNA probes revealed six clusters of rDNA, i.e. six nucleolar organizer regions (NORs), in the heterochromatic short arms of different chromosomes in the haploid male karyotype. This number is exceptionally high for Hymenoptera, which usually have two NORs in the diploid complement. It is noteworthy that these rDNA-FISH experiments represent the first use of this technique on a braconid species using autologous probes. Since Ag-NOR-bands were coincident with C-positive bands on metaphase chromosomes, it was not possible to identify active nucleoli. The physical characteristics of the D. longicaudata karyotype, especially the content and distribution of heterochromatin and the number and location of rDNA clusters, contribute to a better understanding of the structure and organization of braconid chromosomes and provide a basis for genomic and evolutionary studies., Leonela Carabajal Paladino ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
397. Cytogenetic variability among Bradyporinae species (Orthoptera: Tettigoniidae)
- Creator:
- Warchalowska-Sliwa, Elzbieta, Grzywacz, Beata, Maryanska-Nadachowska, Anna, Karamysheva, Tatyana V., Chobanov, Dragan P., and Heller, Klaus-Gerhard
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Orthoptera, Ephippigerini, Bradyporini, karyotype evolution, chromosome fusion, B chromosomes, FISH, rDNA, 2, and 59
- Language:
- English
- Description:
- 1_Chromosomes of six European species (one with two subspecies) of Orthoptera belonging to the tribes Ephippigerini and Bradyporini were analyzed using C-banding, Ag-NOR, DAPI (AT-rich)/CMA3 (GC-rich) staining and fluorescence in situ hybridization (FISH) using the 18S rDNA and (TTAGG)n telomeric probes with the aim to better understand chromosomal organization and evolutionary relationships between genera and subgenera within and across both tribes. The evolution of karyotypes was studied in terms of changes in chromosome number (2n) and morphology (FN, the fundamental number – i.e. the number of chromosome arms including the X chromosome). The ancestral 2n = 31 was reduced to 2n = 29 (FN = 31) and 27 (FN = 31) by one or two Robertsonian fusions in the Ephippigerini. Whereas in the Bradyporini 2n = 27 (FN = 32) as a result of two Robertsonian translocations and a pericentric inversion in the X chromosome. The quantity of heterochromatin in GC-rich regions distinguished the karyotypes of Ephippigerini (only a single CG-rich band on one autosome pair) from those of Bradyporini (CG-rich bands on all chromosomes). FISH using the 18S rDNA probe localized 1–3 rDNA clusters to autosomes and/or to the X chromosome in all species examined. The rDNA loci coincided with active NORs as determined by Ag-NOR staining. A comparison of the location of the single NOR/rDNA in two species of the genus Steropleurus (Ephippigerini) suggests that the reduced chromosome number in S. pseudolus results from a Robertsonian fusion between two pairs of autosomes, one of them carrying the NOR/rDNA as in S. stalii (and also in E. ephippiger)., 2_Whereas the karyotypes of three species of the genus Bradyporus, though showing the same chromosome number and morphology, differed in the number and distribution of NORs/rDNA sites [one autosomal in B. (B.) dasypus versus three in B. macrogaster and B. (C.) oniscus, two of them X-linked]. Trends in karyotype diversification of the taxa based on the present data and previous research are discussed. In some individuals belonging to the species Bradyporus (B.) dasypus and B. (C.) m. macrogaster B chromosomes (Bs) were detected: acrocentric (the smallest elements in the complement) and submetacentric (similar to medium-sized autosomes), respectively., Elzbieta Warchalowska-Sliwa ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
398. Cytokiny a biologická léčba
- Creator:
- Ilja Trebichavský
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, molekulární biologie, cytokiny, biologická léčba, molecular biology, cytokines, biologic therapy, 2, and 577
- Language:
- Czech
- Description:
- Cytokiny jsou proteiny, které regulují růst, diferenciaci a aktivaci buněk. Jejich účinek se široce využívá pro léčbu zánětlivých a nádorových onemocnění. Anti-cytokinová léčba je velmi slibná, ale přinese v blízké budoucnosti velké finanční zatížení zdravotnictví., Cytokines are proteins that regulate the growth, differentiation and activation of cells. Their functions are used in therapy of inflammatory diseases and cancer. Antibody blockade of cytokines seems to be very promising, but it will result in considerable financial burden for healthcare in future., and Ilja Trebichavský.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
399. Daily survival and dispersal of adult Rhagonycha fulva (Coleoptera: Cantharidae) in a wooded agricultural landscape I
- Creator:
- Rodwell, Laura E, Day, Jennifer J, Foster, Christopher W, and Holloway, Graham J
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brouci, dlouhověkost, beetles, longevity, Cantharidae, Rhagonycha fulva, Hogweed bonking beetle, soldier beetle, mark re-sighting, movement, settling, landscape connectivity, landscape configuration, 2, and 59
- Language:
- English
- Description:
- Studies of insect population under field conditions to establish survival rates, longevity and dispersal rates are rare in the literature. These types of studies are important and can be used to inform studies of the effects of landscape composition and configuration on levels of biodiversity. Here the Cantharidae beetle, Rhagonycha fulva is studied under field conditions to derive estimates of daily survival rates for both males and females as well as local dispersal rates. Survival was studied at two sites, one in Wales and another in England, whilst dispersal was examined only at the Welsh site. Beetles were marked using different coloured enamel paints at the mid-point of a 200 m linear transect. The beetles were almost exclusively found (and marked) on common hogweed, Heracleum sphondylium. No difference in survival was found between males and females at both of the sites. The survival rates found at the two sites also did not differ. The overall daily survival rate was 0.771 equating with a median longevity of 4.37 days. Casual observations yielded a small number of marked individuals in excess of 400 m away from the point of marking. Movement of males along the transect differed from females. Marked females were never found far from the point of marking whilst males moved further away with time. This difference in behaviour is discussed in terms of hypothesized insect dispersal behaviour following emergence as mobile adults., Laura E. Rodwell, Jennifer J. Day, Christopher W. Foster, Graham J. Holloway., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
400. Daily temperature drop prevents inhibition of photosynthesis in tomato plants under continuous light
- Creator:
- Ikkonen, E. N., Shibaeva, T. G., Rosenqvist, E., and Ottosen, C.-O.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, chlorophyll fluorescence, gas exchange, leaf area, photodamage, stomatal conductance, 2, and 581
- Language:
- Multiple languages
- Description:
- The negative effects of continuous light (CL) seen in tomato plants are often claimed to be linked to effects of offsetting the diurnal rhythm. In this study we tested whether a short-term daily temperature drop prevents the decreased photosynthetic performance seen in tomato plants grown under CL. Tomato (Lycopersicon esculentum Mill.) plantlets were grown at constant temperature of 26°C under 16-h day (16D) or 24-h day (24D) at 150 μmol m-2 s-1 PPFD. Some 24D plants were treated daily by 2 h temperature drop from 26 to 10°C (24D+DROP). Physiological disorder, such as severe leaf chlorosis, a large decrease in net photosynthetic rate, maximal quantum yield of PSII photochemistry, and the effective quantum yield of PSII photochemistry were observed in 24D, but not in 16D and 24D+DROP plants. The daily 2-h drop in temperature eliminated a negative effect of CL on photosynthesis and prevented the development of leaf chlorosis in tomato plants. This could be due to a change in carbohydrate metabolism as the short drop in temperature might allow maintenance of the diurnal rhythms., E. N. Ikkonen, T. G. Shibaeva, E. Rosenqvist, C.-O. Ottosen., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public