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41.
Vrieling H 《Tijdschrift voor diergeneeskunde》2007,132(1):979-980
42.
Summary Phytotron experiments have been carried out to study the effect of different temperatures on the seed set of tetraploid freesias during the raising of the plants and at the time of flowering and pollination.The effect of a relatively low temperature during the growth period is reflected in a comperatively greater number of flowers as a result of an increase in number of ramifications of the peduncle. This sometimes promotes the seed yield notwithstanding that the lower temperature reduces the fertility of each seperate flower. It is clearly proved that the temperature during flowering and pollination affects the fertility of the flower and the ultimate seed yield of the plant. Experiments in our phytotron showed 14°C during the growth period and 20°C at the time of pollination to be the optimum combination for a good seed yield.The effect of a lower night temperature was generally favourable, particularly so when measured by the number of seeds per pollinated flower. 相似文献
43.
RAPD genetic diversity of Albanian olive germplasm and its relationships with other Mediterranean countries 总被引:4,自引:0,他引:4
Angjelina Belaj Zlatko Satovic Hajri Ismaili Dhimitër Panajoti Luis Rallo Isabel Trujillo 《Euphytica》2003,130(3):387-395
RAPD markers were used for the study of 19Albanian olive cultivars and two wild olives (oleasters). A total of 76polymorphic
bands (4.8 polymorphic markers per primer) out of 107 reproducible were obtained using 16 primers. The number of bands per
primer ranged from 4 to 10,whereas the number of polymorphic bands ranged from 1 to 9, corresponding to 71%of the total amplification
products. All the accessions could be identified by the combination of four primers: OPA-19;OPA-02; OPK-16 and OPP-19. The
dendrogram,based on Jaccard's index, included three major groups according to their origin: 1)most of the cultivars from the
area of Berat (South of Albania) 2) cultivars from the Centre and Centre-North of Albania and3) cultivars from the Centre
and North-West of Albania along with the oleaster from Elbasan. In order to evaluate the origin of Albanian cultivars they
were compared to those diffused in other countries like Greece, Italy and Turkey, due to geographical and historical affinity
among these countries, by using a one way AMOVA. Although most of the genetic diversity was attributable to differences among
cultivars within each country (91.47%) significantφ-values among countries(φst = 0.085; p < 0.001)suggested the existence of RAPD phenotypic differentiation. Significant φ-values in all pairs formed by Albania with
the other countries were observed. These results are consistent with the autochthonous origin of Albanian cultivars.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
44.
Summary Genetics of resistance to Ascochyta fabae Speg. in Vicia faba L. was studied with a final objective to develop resistant faba bean varieties to Ascochyta blight. The study was conducted separately on 3 single spore isolates (AF10-2 and AF13-2 from Tunisia and AF4-3 from France) and belonging to different groups of virulence (GV1 and GV2). Important general combining ability (GCA) effects were found especially with isolates AF10-2 and AF4-3. Specific combining ability (SCA), although significant for the 3 isolates, was important only with AF13 -2, but less important than GCA. Additive gene effects were predominant to non-additive effects. Lines 29H and A8817 transmitted to their progenies resistance to the 3 isolates, whereas 14–12 and 19TB conferred resistance to their progenies only with isolates AF13-2 and AF4-3, respectively. In the material studied, resistance was generally controlled by dominant genes but also could be attributed to recessive genes although less frequent. Analysis of segregation in the F2 of 2 crosses between the resistant lines (A8817 and 29H) and the susceptible line (14–12) with isolate AF4-3 revealed dominant monogenic control at the level of leaves in the 2 resistant lines and, in addition, a recessive gene controlling resistance of stems. Non-allelic interactions were occasionally manifested and their origin appeared to be due to line 19TB. A recurrent selection scheme was proposed with the objective to develop improved open-pollination populations and synthetic varieties responding to the objective of the national Tunisian research programme on faba bean. 相似文献
45.
Rondini L Peyrat-Maillard MN Marsset-Baglieri A Berset C 《Journal of agricultural and food chemistry》2002,50(10):3037-3041
The bioavailability of ferulic acid (FA; 3-methoxy-4-hydroxycinnamic acid) and its metabolites was investigated in rat plasma and urine after an oral short-term ingestion of 5.15 mg/kg of FA. Free FA, glucuronoconjugates, and sulfoconjugates were quickly detected in plasma with a peak of concentration found 30 min after ingestion. Sulfoconjugates were the main derivates ( approximately 50%). In urine, the cumulative excretion of total metabolites reached a plateau 1.5 h after ingestion, and approximately 40% were excreted by this way. Free FA recovered in urine represented only 4.9 +/-1.5% of the native FA consumed by rats. Glucuronoconjugates and sulfoconjugates represented 0.5 +/- 0.3 and 32.7 +/- 7.3%, respectively. These results suggested that a part of FA incorporated in the diet was quickly absorbed and largely metabolized in sulfoconjugates before excretion in urine. 相似文献
46.
Barillari J Cervellati R Paolini M Tatibouët A Rollin P Iori R 《Journal of agricultural and food chemistry》2005,53(26):9890-9896
The most promising among glucosinolates (GLs) are those bearing in their aglycon an extra sulfur function, such as glucoraphasatin (4-methylthio-3-butenyl GL; GRH) and glucoraphenin (4-methylsulfinyl-3-butenyl GL; GRE). The GRE/GRH redox couple is typically met among secondary metabolites of Raphanus sativus L. and, whereas GRE prevails in seeds, GRH is the major GL in full-grown roots. During the 10 days of sprouting of R. sativus seeds, the GRE and GRH contents were determined according to the Eurpean Union official method (ISO 9167-1). In comparison to the seeds, the GRE content in sprouts decreased from about 90 to about 12 micromol g(-1) of dry weight (dw), whereas a 25-fold increase--from about 3 to 76 micromol g(-1) of dw--of the GRH content was measured. An efficient pure GRH gram-scale production process from R. sativus (kaiware daikon) sprouts resulted in significant yield improvement of up to 2.2% (dw basis). The reaction of GRH with both H2O2 and ABTS*+ radical cation was investigated. Whereas H2O2 oxidation of GRH readily resulted in complete transformation into GRE, ABTS*+ caused complete decay of the GL. Even though not directly related to its radical scavenging activity, the assessed reducing capacity of GRH suggests that R. sativus sprouts might possess potential for health benefits. 相似文献
47.
The effects of schisandrin B (Sch B) and its analogs on solar irradiation-induced oxidative injury were examined in BJ human fibroblasts. Sch B and schisandrin C (Sch C) increased cellular reduced glutathione (GSH) level and protected against solar irradiation-induced oxidative injury. The photoprotection was paralleled by decreases in the elastases-type protease activity and matrix-metalloproteinases-1 expression in solar-irradiated fibroblasts. The cytochrome P-450-mediated metabolism of Sch B or Sch C caused ROS production. The results suggest that by virtue of its pro-oxidant action and the subsequent glutathione antioxidant response, Sch B or Sch C may offer the prospect of preventing skin photo-aging. 相似文献
48.
Observed flow compensation associated with the MOC at 26.5 degrees N in the Atlantic 总被引:3,自引:0,他引:3
Kanzow T Cunningham SA Rayner D Hirschi JJ Johns WE Baringer MO Bryden HL Beal LM Meinen CS Marotzke J 《Science (New York, N.Y.)》2007,317(5840):938-941
The Atlantic meridional overturning circulation (MOC), which provides one-quarter of the global meridional heat transport, is composed of a number of separate flow components. How changes in the strength of each of those components may affect that of the others has been unclear because of a lack of adequate data. We continuously observed the MOC at 26.5 degrees N for 1 year using end-point measurements of density, bottom pressure, and ocean currents; cable measurements across the Straits of Florida; and wind stress. The different transport components largely compensate for each other, thus confirming the validity of our monitoring approach. The MOC varied over the period of observation by +/-5.7 x 10(6) cubic meters per second, with density-inferred and wind-driven transports contributing equally to it. We find evidence for depth-independent compensation for the wind-driven surface flow. 相似文献
49.
Temporal variability of the Atlantic meridional overturning circulation at 26.5 degrees N 总被引:4,自引:0,他引:4
Cunningham SA Kanzow T Rayner D Baringer MO Johns WE Marotzke J Longworth HR Grant EM Hirschi JJ Beal LM Meinen CS Bryden HL 《Science (New York, N.Y.)》2007,317(5840):935-938
The vigor of Atlantic meridional overturning circulation (MOC) is thought to be vulnerable to global warming, but its short-term temporal variability is unknown so changes inferred from sparse observations on the decadal time scale of recent climate change are uncertain. We combine continuous measurements of the MOC (beginning in 2004) using the purposefully designed transatlantic Rapid Climate Change array of moored instruments deployed along 26.5 degrees N, with time series of Gulf Stream transport and surface-layer Ekman transport to quantify its intra-annual variability. The year-long average overturning is 18.7 +/- 5.6 sverdrups (Sv) (range: 4.0 to 34.9 Sv, where 1 Sv = a flow of ocean water of 10(6) cubic meters per second). Interannual changes in the overturning can be monitored with a resolution of 1.5 Sv. 相似文献
50.