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1.
Capsicum baccatum, commonly known as ají, has been reported as a source of variation for many different traits to improve common pepper (C. annuum), one of the most important vegetables in the world. However, strong interspecific hybridization barriers exist between them. A comparative study of two wide hybridization approaches for introgressing C. baccatum genes into C. annuum was performed: i) genetic bridge (GB) using C. chinense and C. frutescens as bridge species; and, ii) direct cross between C. annuum and C. baccatum combined with in vitro embryo rescue (ER). A diverse and representative collection of 18 accessions from four cultivated species of Capsicum was used, including C. annuum (12), C. baccatum (3), C. chinense (2), and C. frutescens (1). More than 5000 crosses were made and over 1000 embryos were rescued in the present study. C. chinense performed as a good bridge species between C. annuum and C. baccatum, with the best results being obtained with the cross combination [C. baccatum (♀) × C. chinense (♂)] (♀) × C. annuum (♂), while C. frutescens gave poor results as bridge species due to strong prezygotic and postzygotic barriers. Virus-like-syndrome or dwarfism was observed in F1 hybrids when both C. chinense and C. frutescens were used as female parents. Regarding the ER strategy, the best response was found in C. annuum (♀) × C. baccatum (♂) crosses. First backcrosses to C. annuum (BC1s) were obtained according to the crossing scheme [C. annuum (♀) × C. baccatum (♂)] (♀) × C. annuum (♂) using ER. Advantages and disadvantages of each strategy are discussed in relation to their application to breeding programmes. These results provide breeders with useful practical information for the regular utilization of the C. baccatum gene pool in C. annuum breeding.  相似文献   

2.
The subfamily Candoninae is the most diversified group in the Upper Miocene freshwater deposits of the Turiec Basin (Slovakia). The presence of Candoninae morphologically related to recent as well as Central Paratethys species reveals a problem between taxonomy based on soft body (zoological classification) and taxonomy based on hard part (paleontological classification). The current zoological classification is applied which reflects the real taxonomical relationships between species. The accent was put on the carapace morphological details to distinguish the species. Three described groups (Candona candida, C. neglecta and Candona of group indet) contain 7 new species – Candona densa, C. mocki, C. imaginaria, C. margueritae, C. singularis, C. sirveni et C. vahica.  相似文献   

3.
《Phytochemistry》1999,52(8):1387-1390
The release of volatile compounds from a flower of Hydrosme rivieri was recorded during the whole flowering period (7 days). The quantities of six odour components (dimethyl disulphide, dimethyl trisulphide, n-alkanes C10, C11, C12 and C13) forming the main part of emanating volatiles were plotted versus time. n-Alkanes started to emanate 3 days before the release of dimethyl disulphide and dimethyl trisulphide (the components with a rotting meat odour).  相似文献   

4.
Treatment of methyl 2,3-anhydro-5-deoxy-α-d-ribofuranoside with lithium dimethyl cuprate gave methyl 2,5-dideoxy-2-C-methyl-α-d-arabinofuranoside (54% yield) and methyl 3,5-dideoxy-3-C-methyl-α-d-xylofuranoside (10%). The former was converted into its 3-O-acetyl and 3-O-benzyl derivatives, which, upon acid hydrolysis, afforded 3-O-acetyl- and 3-O-benzyl-2,5-dideoxy-2-C-methyl-d-arabinofuranose in 60–75% overall yield. Treatment of the 3-O-benzyl compound with ethanethiol in the presence of trifluoromethanesulfonic acid afforded 3-O-benzyl-2,5-dideoxy-2-C-methyl-d-arabinose diethyl dithioacetal (20%) and ethyl 3-O-benzyl-2,5-dideoxy-2-C-methyl-1-thio-α-d-arabinoside (73%). The former, which was also available from the latter by equilibration in acidic ethanethiol, was acetylated at O-4 and the product converted into the corresponding dimethyl acetal (85% overall yield). This compound was, after debenzylation, hydrolyzed with acid, to provide 4-O-acetyl-2,5-dideoxy-2-C-methyl-d-arabinose in 70% overall yield.  相似文献   

5.
Six di-C-glycosylflavones isolated from Lespedeza capitata leaves were identified as schaftoside, neoschaftoside, isoschaftoside, carlinoside, neocarlinoside and a new natural compound: isocarlinoside (6-C-α-l-arabinopyranosyl-8-C-β-d-glucopyranosylluteolin).  相似文献   

6.
Culicoides brevitarsis is a vector of the bluetongue virus (BTV), which infects sheep and cattle. It is an invasive species in Australia with an assumed Asian/South East Asian origin. Using one mitochondrial marker (i.e., part of the cytochrome oxidase subunit I gene) and six nuclear markers, we inferred population genetic structure and possible incursion pathways for Australian C. brevitarsis. Nine mitochondrial haplotypes, with low nucleotide sequence diversity (0.0–0.7%) among these, were identified in a sample of 70 individuals from seven sites. Both sets of markers revealed a homogeneous population structure, albeit with evidence of isolation by distance and two genetically distinct clusters distributed along a north-to-south cline. No evidence of a cryptic species complex was found. The geographical distribution of the mitochondrial haplotypes is consistent with at least two incursion pathways into Australia since the arrival of suitable livestock hosts. By contrast, 15 mitochondrial haplotypes, with up to four times greater nucleotide sequence diversity (0.0–2.9%) among these, were identified in a sample of 16 individuals of the endemic C. marksi (sampled from a site in South Australia and another in New South Wales). A phylogenetic tree inferred using the mitochondrial marker revealed that the Australian and Japanese samples of C. brevitarsis are as evolutionarily different from one another as some of the other Australian species (e.g., C. marksi, C. henryi, C. pallidothorax) are. The phylogenetic tree placed four of the species endemic to Australia (C. pallidothorax, C. bundyensis, C. marksi, C. henryi) in a clade, with a fifth such species (C. bunrooensis) sharing a common ancestor with that clade and a clade comprising two Japanese species (C. verbosus, C. kibunensis).  相似文献   

7.
Vu JC  Allen LH  Bowes G 《Plant physiology》1984,76(3):843-845
Ribulose bisphosphate carboxylase/oxygenase (RuBPCase) from several plants had substantially greater activity in extracts from lightexposed leaves than dark leaves, even when the extracts were incubated in vitro with saturating HCO3 and Mg2+ concentrations. This occurred in Glycine max, Lycopersicon esculentum, Nicotiana tabacum, Panicum bisulcatum, and P. hylaeicum (C3); P. maximum (C4 phosphoenolpyruvate carboxykinase); P. milioides (C3/C4); and Bromelia pinguin and Ananas comosus (Crassulacean acid metabolism). Little or no difference between light and dark leaf extracts of RuBPCase was observed in Triticum aestivum (C3); P. miliaceum (C4 NAD malic enzyme); Zea mays and Sorghum bicolor (C4 NADP malic enzyme); Moricandia arvensis (C3/C4); and Hydrilla verticillata (submersed aquatic macrophyte). It is concluded that, in many plants, especially Crassulacean acid metabolism and C3 species, a large fraction of ribulose-1,5-bisphosphate carboxylase/oxygenase in the dark is in an inactivatable state that cannot respond to CO2 and Mg2+ activation, but which can be converted to an activatable state upon exposure of the leaf to light.  相似文献   

8.
Complementary to our previous project on the molecular phylogeny of Camphorosmeae, the leaf anatomy of ca. 35 species including all non-Australian and selected Australian species was studied by use of light microscopy. Nine anatomical leaf types were described, compared to previous classifications, and discussed with regard to their putative evolution on the background of phylogenetic trees. Particular emphasis was given to the relationships between the C3 and C4 leaf types: Chenolea type (C3), Eokochia type (C3), Neokochia type (C3), Sedobassia type (C3/C4 intermediate), Bassia prostrata type (C4), B. muricata type (C4), B. eriantha type, B. lasiantha type (C4), Camphorosma type (C4). The main results and conclusions were: (1) Two unusual new C3 leaf types: Chenolea with microfenestrate chlorenchyma, Eokochia with unique complex vascular bundles; (2) Sedobassia interpreted as anatomically C3/C4 intermediate by kranz-like bundle sheath cells is the first C3/C4 intermediate in Camphorosmeae and found in a derived position; (3) Neokochia type detected as the likely starting point for all four C4 leaf types and for the C3/C4 intermediate; (4) hypodermis of C4 types originated from outermost chlorenchyma layer of C3 types and lost multiple times during further evolution; (5) atriplicoid Bassia. lasiantha type without water storage tissue evolved from kochioid B. muricata type; (6) two independent gains of C4 photosynthesis, one in Bassia and one in Camphorosma; (7) depending on the lineage, leaf architecture remains comparatively stable (Australian Camphorosmeae) or shows an unexpected plasticity (Bassia scoparia group).  相似文献   

9.
The structure and composition of the cutin monomers from the flower petals of Vicia faba were determined by hydrogenolysis (LiAlH4) or deuterolysis (LiAlD4) followed by thin layer chromatography and combined gas-liquid chromatography and mass spectrometry. The major components were 10, 16-dihydroxyhexadecanoic acid (79.8%), 9, 16-dihydroxyhexadecanoic acid (4.2%), 16-hydroxyhexadecanoic acid (4.2%), 18-hydroxyoctadecanoic acid (1.6%), and hexadecanoic acid (2.4%). These results show that flower petal cutin is very similar to leaf cutin of V. faba. Developing petals readily incorporated exogenous [1-14C]palmitic acid into cutin. Direct conversion of the exogeneous acid into 16-hydroxyhexadecanoic acid, 10, 16-dihydroxy-, and 9, 16-dihydroxyhexadecanoic acid was demonstrated by radio gas-liquid chromatography of their chemical degradation products. About 1% of the exogenous [1-14C]palmitic acid was incorporated into C27, C29, and C31n-alkanes, which were identified by combined gas-liquid chromatography and mass spectrometry as the major components of the hydrocarbons of V. faba flowers. The radioactivity distribution among these three alkanes (C27, 15%; C29, 48%; C31, 38%) was similar to the per cent composition of the alkanes (C27, 12%; C29, 43%; C31, 44%). [1-14C]Stearic acid was also incorporated into C27, C29, and C31n-alkanes in good yield (3%). Trichloroacetate, which has been postulated to be an inhibitor of fatty acid elongation, inhibited the conversion of [1-14C]stearic acid to alkanes, and the inhibition was greatest for the longer alkanes. Developing flower petals also incorporated exogenous C28, C30, and C32 acids into alkanes in 0.5% to 5% yields. [G-3H]n-octacosanoic acid (C28) was incorporated into C27, C29, and C31n-alkanes. [G-3H]n-triacontanoic acid (C30) was incorporated mainly into C29 and C31 alkanes, whereas [9, 10, 11-3H]n-dotriacontanoic acid (C32) was converted mainly to C31 alkane. Trichloroacetate inhibited the conversion of the exogenous acids into alkanes with carbon chains longer than the exogenous acid, and at the same time increased the amount of the direct decarboxylation product formed. These results clearly demonstrate direct decarboxylation as well as elongation and decarboxylation of exogenous fatty acids, and thus constitute the most direct evidence thus far obtained for an elongation-decarboxylation mechanism for the biosynthesis of alkanes.  相似文献   

10.
Near-infrared reflectance spectroscopy (NIRS) has been used extensively in the forage industry for rapid measurement of forage constituents and could be useful for determining quality of biomass feedstocks at the point of delivery. In previous work, we developed an assay that partitions feedstock carbohydrates based on their availability to be converted to fermentable sugars, including non-structural carbohydrates (C N), biochemically available carbohydrates (C B) with an associated first-order availability rate constant (k B), and unavailable carbohydrates (C U ). Additional quality parameters measured included neutral detergent lignin (NDL), total available carbohydrates (C A), and total carbohydrates (C T). We evaluated the variability of biomass quality parameters in a set of corn stover samples and developed calibration equations for determining parameter values using NIRS. Fifty-two corn stover samples harvested in Iowa and Wisconsin in 2005 and 2006 were analyzed using a high-throughput assay for determining feedstock quality for biochemical conversion. Non-structural carbohydrates ranged from 84 to 155?g?kg?1 dry matter (DM); C B ranged from 354 to 557?g?kg?1 DM; k B ranged from 0.199 to 0.330?h?1; C A ranged from 463 to 699?g?kg?1 DM, and NDL ranged from 32 to 74?g?kg?1 DM. Significant differences (P?<?0.0001) among samples were observed for all parameters, except k B. Near-infrared reflectance spectroscopy calibration equations were developed for C N, C B, C A, C U , C T, and NDL. It was not possible to generate a meaningful calibration equation for k B. There is significant variability within the corn stover population for several key quality-related carbohydrate and lignin constituents which can be predicted reliably using NIRS.  相似文献   

11.
Wax on leaves of Agropyron intermedium contains hydrocarbons (11%, C27–C33), esters (11%, C32–C60), free alcohols (180%, C26) 25-oxohentriacontane-14,16-dione (17%), 10-oxohentriacontane-14,16-dione (5y%), 25-hydroxyhentriacontane-14,16-dione (12%) and 26-hydroxyhentriacontane-14,16-dione (2%). Wax on spikes contains additional components, C25–C33cis 9-alkenes (32% of hydrocarbons), and more β-diketones, 25-hydroxy (17%) and 26-hydroxy (3%) hentriacontane-14,16-diones, 10,25-dioxohentriacontane-14,16-dione (1%) and 4-hydroxy-25-oxo-(2%), 25-hydroxy-10-oxo-(1.3%) and 26-hydroxy-10-oxo-(0.7%) hentriacontane-14,16-diones; free alcohols were very minor components (1%, C24–C32).  相似文献   

12.
Transfer of C4 photosynthetic traits was studied through hybridization of Flaveria trinervia (Spreng.) Mohr (C4) and Flaveria brownii A.M. Powell (C4-like) with Flaveria linearis Lag. (C3-C4) and the C3 species Flaveria pringlei Gandoger (C3). Fertility was low, based on irregular chromosome pairing and low pollen stainability, except in F. brownii × F. linearis which had bivalent pairing and 76% stainable pollen. Hybrids had apparent photosynthesis values of 71 to 148% of the midparental means, while the CO2 compensation concentration was similar to the C4 or C4-like parent, except in hybrids having the C3 species F. pringlei as a parent. Inhibition of apparent photosynthesis by O2, and phosphoenolpyruvate carboxylase and NADP-malic enzyme activities and subunit levels in the hybrids were closer to the C3 or C3-C4 parent. The species F. brownii and F. trinervia were equal in their capacity to transfer reduced O2 inhibition of AP and CO2 compensation concentration values to hybrids with F. linearis (C3-C4), although hybrids with F. trinervia had higher PEPC activity. The O2 inhibition of AP was correlated with the logarithm of activities of phosphoenolpyruvate carboxylase (r = −0.95) and NADP-malic enzyme (r = −0.87). These results confirm that C4 traits can be transferred by hybridization of C3-C4 and C4 or C4-like species, with a higher degree of C4 photosynthesis than exists in C3-C4 species, and at least in F. brownii × F. linearis, fertile progeny are obtained.  相似文献   

13.
14.
In this paper, we describe the synthesis of 4′-C-aminoalkyl-2′-O-methylnucleosides and the properties of RNAs containing these analogs. Phosphoramidites of 4′-C-aminoethyl and 4′-C-aminopropyl-2′-O-methyluridines were prepared using glucose as starting material, and RNAs containing the analogs were synthesized using the phosphoramidites. Thermal denaturation studies revealed that these nucleoside analogs decreased the thermal stabilities of double-stranded RNAs (dsRNAs). Results of NMR, molecular modeling, and CD spectra measurements suggested that 4′-C-aminoalkyl-2′-O-methyluridine adopts an C2′-endo sugar puckering in dsRNA. The 4′-C-aminoalkyl modifications in the passenger strand and the guide strand outside the seed region were well tolerated for RNAi activity of siRNAs. Single-stranded RNAs (ssRNAs) and siRNAs containing the 4′-C-aminoethyl and 4′-C-aminopropyl analogs showed high stability in buffer containing bovine serum. Thus, siRNAs containing the 4′-C-aminoethyl and 4′-C-aminopropyl analogs are good candidates for the development of therapeutic siRNA molecules.  相似文献   

15.
Monoacylglycerols containing α-branched-β-hydroxylated fatty acids (mycolic acids) ranging from C42 to C50 and from C60 to C66, were isolated from Gordona lentifragmenta and from G. bronchialis, respectively. On the other hand, G. rubropertincta showed only a monoacylglycerol fraction which released non-hydroxylated fatty acids; they were identified as C16:0-, C16:1,- C18:1- and branched C19:0-fatty acids. This last component was identified as 10-methyl octadecanoic acid (tuberculostearic acid).  相似文献   

16.

Background

Whether non-communicable diseases (NCDs) are diseases of poverty or affluence in low-and-middle income countries has been vigorously debated. Most analyses of NCDs have used self-reported data, which is biased by differential access to healthcare services between groups of different socioeconomic status (SES). We sought to compare self-reported diagnoses versus standardised measures of NCD prevalence across SES groups in India.

Methods

We calculated age-adjusted prevalence rates of common NCDs from the Study on Global Ageing and Adult Health, a nationally representative cross-sectional survey. We compared self-reported diagnoses to standardized measures of disease for five NCDs. We calculated wealth-related and education-related disparities in NCD prevalence by calculating concentration index (C), which ranges from −1 to +1 (concentration of disease among lower and higher SES groups, respectively).

Findings

NCD prevalence was higher (range 5.2 to 19.1%) for standardised measures than self-reported diagnoses (range 3.1 to 9.4%). Several NCDs were particularly concentrated among higher SES groups according to self-reported diagnoses (Csrd) but were concentrated either among lower SES groups or showed no strong socioeconomic gradient using standardized measures (Csm): age-standardised wealth-related C: angina Csrd 0.02 vs. Csm0.17; asthma and lung diseases Csrd0.05 vs. Csm0.04 (age-standardised education-related Csrd 0.04 vs. Csm0.05); vision problems Csrd 0.07 vs. Csm0.05; depression Csrd 0.07 vs. Csm0.13. Indicating similar trends of standardized measures detecting more cases among low SES, concentration of hypertension declined among higher SES (Csrd 0.19 vs. Csm 0.03).

Conclusions

The socio-economic patterning of NCD prevalence differs markedly when assessed by standardized criteria versus self-reported diagnoses. NCDs in India are not necessarily diseases of affluence but also of poverty, indicating likely under-diagnosis and under-reporting of diseases among the poor. Standardized measures should be used, wherever feasible, to estimate the true prevalence of NCDs.  相似文献   

17.
Although vitrification is the current routine method for human embryo cryopreservation, it may cause detrimental effects. The aim of this study was to evaluate the effect of supplementing in vitro culture (IVC) media and/or vitrification solutions (VS) with Resveratrol on the presence of apoptotic markers, reactive oxygen species (ROS) level, glutathione (GSH) content and relative gene abundance. Abattoir-derived oocytes were matured and fertilized in vitro according to a standard procedure. Zygotes were cultured in IVC medium supplemented with or without 0.5 μM Resveratrol (CR, C respectively). On day 7, blastocysts were vitrified using the minimum volume vitrification method supplementing VS with (CVR, CRVR) or without (CV-, CRV) 0.5 μM Resveratrol. After warming, embryonic quality parameters were evaluated. Survival rates were significantly lower in CRVR group compared with CRV group, but no differences in hatching rate were observed between groups. Vitrification/warming process did not alter total cell number or the presence of apoptotic or dead cells, but CRV and CRVR groups presented a significant increase in dead cells (P < 0.05 by ANOVA). Resveratrol supplementation in VS (CVR) restored GSH content (P < 0.05) to the level found in the CR group. Vitrification/warming process significantly increased the expression of FOXO3A, PNPLA2, BCL2L1 and BAX genes (P < 0.05). Resveratrol addition to IVC medium or VS partially compensated this increase for FOXO3A and PNPLA2 (P < 0.05) but not for BCL2L1 and BAX. In conclusion, supplementation of IVC media or VS with 0.5 μM resveratrol may help embryos to partially restore the initial quality they had before the cryopreservation process.  相似文献   

18.
Klaus Haas 《Phytochemistry》1982,21(3):657-659
The mosses Andreaea rupestris, Pogonatum aloides and P. urnigerum contain surface waxes in amounts of 0.05–0.12% dry wt. The waxes consisted of esters (C38-C54), primary alcohols (C20-C32), free fatty acids (C16-C30), and alkanes (C21-C31). Additionally, aldehydes (C22-C30) were major constituents in the wax of P. urnigerum. The classes and their chain length distributions in the surface waxes of these mosses are comparable to those of epicuticular waxes of higher plants.  相似文献   

19.
Epicuticular wax isolated from the cotyledons and primary needles of 10-week-old Pinus radiata seedlings is similar in composition and contains 86% neutral compounds, viz. alkyl esters (25%, C24–C64), nonacosan-10-ol (52%), heptacosane-5,10-diol (2%), nonacosane-4,10-diol, nonacosane-5,10-diol, and nonacosane-10,13-diol (total 12%) and estolides, MW ca 800 (2%), MW ca 1100 (6%), and MW ca 1500 (1%). The acidic fraction (14%) contains n-acids (78%, C12–C32) and diterpene acids (22%, mainly abieta-8,11,13-trien-18-oic, with lesser amounts of pimara-8(14),15-dien-18-oic, isopimara-7,15-dien-18-oic and hydroxylated aromatic, diene and mono-ene acids). Wax isolated from primary needles of 1-yr-old seedlings had a similar neutral fraction composition, but the acidic fraction contained predominantly the diterpene acid mixture, with only trace amounts of n-acids. The wax from 1-yr-old secondary, needles from P. radiata forest trees aged 5 yr and 40 yr contained an acid fraction (12% 5 yr, 17% 40 yr trees) comprising the diterpene acid mixture, with trace amounts of n-acids together with ω-hydroxy acids (C12, C14 and C16). The neutral fraction from both young and old trees had a similar composition containing alkyl esters (7%, C24–C66), estolides (90%, MW 566-ca 1500), nonacosan-10-ol (2%) and the heptacosane and nonacosane diols (1%). During growth and maturation of P. radiata, the nonacosan-10-ol content of the needle wax decreases while the proportion of estolides and diterpene acids increases, the latter probably being located around the stomatal pore.  相似文献   

20.
Genetic Relationships Within and Between Capsicum Species   总被引:1,自引:0,他引:1  
Genetic relationships were estimated among 24 accessions belonging to 11 species of Capsicum, using 2,760 RAPD markers based on touch-down polymerase chain reactions (Td-RAPD-PCR). These markers were implemented in analyses of principal coordinates, unweighted pair group mean average, and 2,000 bootstrap replications. The accessions were divided into four groups, corresponding to previously described Capsicum complexes: C. annuum complex (CA), C. baccatum complex (CB), C. pubescens complex (CP), and C. chacoense accessions (CA/B). Their overall mean genetic similarity index was 0.487 ± 0.082, ranging from 0.88 to 0.32, based on Jaccard’s coefficient. The highest genetic variation was observed among the accessions in CP; the accessions in CB had a low level of variation as judged from the standard deviations of the genetic similarity indices. Based on the Td-RAPD-PCR markers, the 24 accessions were divided into four major groups, three of which corresponded to the three distinct Capsicum complexes. Accessions of C. chacoense were found to be equally related to complexes CA, CB, and CP.  相似文献   

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