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1.
N. T. Chang R. E. Lynch F. A. Slansky B. R. Wiseman D. H. Habeck 《Entomologia Experimentalis et Applicata》1987,45(1):29-35
Food utilization by larvae of the fall armyworm (Spodoptera frugiperda [J. E. Smith]) (Lepidoptera: Noctuidae), showed greater consumption of corn (Zea mays L.) than pinto bean diet, Tifton 10, or Coastal bermudagrass (Cynodon dactylon [L.] Pers.). Transfer of larvae from diet to susceptible grasses such as corn, Tifton 10 or Coastal produced differences in growth rates as a result of food consumption rates. Transfer of larvae from diet to resistant grasses such as common centipedegrass (Eremochola ophiuroides [Munro] Hack) Tifton 292 bermudagrass, and zoysiagrass (Zoysia sp.) reduced larval growth as a result of low consumption rates and/or greater metabolic expenditures. Larvae initially fed Tifton 10, Coastal, or centipedegrass before feeding on corn grew significantly faster than when they fed continuously on corn.
Résumé Des chenilles de S. frugiperda ont consommé plus de maïs (Zea mays), que d'un régime à base de Phaseolus vulgaris de la variété Pinto, ou de Tifton 10, ou de Cynodon dactylon de la variété Coastal. Des chenilles, transférées du régime artificiel sur des plantes sensibles comme le maïs, le Tifton 10 ou le Coastal, ont présenté des taux de croissance différents provenant de modifications de leur consommation. Le transfert du régime à des plantes résistantes, telles que Eremochola ophiuroides, Tifton 292, C. dactylon et Zoysia sp., a entraîné une diminution de la croissance larvaire par suite d'une plus faible consommation et/ou de dépenses métaboliques plus élevées. Des chenilles ayant consommé du Tifton 10, du Coastal ou de l'E. ophiuroides avant de consommer du maïs, se sont développées significativement plus vite que celles qui s'étaient alimentées continuellement sur maïs.相似文献
2.
Folkert Reck Matthias Springer Ernst Meinjohanns Hans Paulsen Inka Brockhausen Harry Schachter 《Glycoconjugate journal》1995,12(6):747-754
UDP-GlcNAc:Man1-3R 1-2-N-acetylglucosaminyltransferase I (GlcNAc-T I; EC 2.4.1.101) catalyses the conversion of [Man1-6(Man1-3)Man1-6][Man1-3]Man-O-R to [Man1-6(Man1-3)Man1-6] [GlcNAc1-2Man1-3]Man-O-R (R=1-4GlcNAc1-4GlcNAc-Asn-X) and thereby controls the conversion of oligomannose to complex and hybrid asparagine-linked glycans (N-glycans). GlcNAc-T I also catalyses the conversion of Man1-6(Man1-3)Man-O-octyl to Man1-6(GlcNAc1-2Man1-3)Man-O-octyl. We have therefore tested a series of synthetic analogues of Man1-6(Man1-3)Man-O-octyl as substrates and inhibitors for rat liver GlcNAc-T I. The 2-deoxy and the 3-, 4- and 6-O-methyl derivatives are all good substrates confirming previous observations that the hydroxyl groups of the Man1-6 residue do not play major roles in the binding of substrate to enzyme. In contrast, all four hydroxyl groups on the Man1-3 residue are essential since the corresponding deoxy derivatives either do not bind (2- and 3-deoxy) or bind very poorly (4- and 6-deoxy) to the enzyme. The 2- and 3-O-methyl derivatives also do not bind to the enzyme. However, the 4-O-methyl derivative is a substrate (K
m
=2.6mm) and the 6-O-methyl compound is a competitive inhibitor (K
i=0.76mm). We have therefore synthesized various 4- and 6-O-alkyl derivatives, some with reactive groups attached to anO-pentyl spacer, and tested these compounds as reversible and irreversible inhibitors of GlcNAc-T I. The 6-O-(5-iodoacetamido-pentyl) compound is a specific time dependent inhibitor of the enzyme. Four other 6-O-alkyl compounds showed competitive inhibition while the remaining compounds showed little or no binding indicating that the electronic properties of the attachedO-pentyl groups influence binding.Abbreviations GlcNAc-T I
UDP-GlcNAc:Man1-3R 1-2-N-acetylglucosaminyltransferase I (EC 2.4.1.101)
- GlcNAc-T II
UDP-GlcNAc:Man1-6R 1-2-N-acetylglucosaminyltransferase II (EC 2.4.1.143)
- MES
2-(N-morpholino)ethane sulfonic acid monohydrate 相似文献
3.
P. K. Gupta G. Fedak 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(6):816-821
Summary Meiotic pairing in Triticum turgidum cv. Ma (4x) with a mean chiasmata frequency of 27.16 per cell was compared with chiasmata frequencies in its hybrids with several triticale strains, Chinese Spring wheat and its addition lines for Imperial rye chromosomes 4R and 6R. In hybrids between Ma and x Triticosecale cv. Rosner the chiasmata frequency was marginally reduced by an average of 1.25%, by 8.8% in hybrids with x Triticosecale cv. DRIRA HH and by 6.7% with DRIRA EE (lacking 90% telomeric heterochromatin from chromosome arm 7RL). In pentaploid hybrids between Ma and T. aestivum cv. Chinese Spring the reduction was an average of 10.30%, while addition lines with rye chromosome 6R reduced chiasmata frequencies by an average of 7.4% and rye addition line for 4R showed the greatest depression in chiasmata frequency in hybrids by a 25.04% reduction. An interchange difference involving long chromosome segments was observed between Ma and Rosner.Contribution No. 819 Ottawa Research Station 相似文献
4.
E. Millet 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(1):105-107
Summary The phenology and build-up of spikelet number under 10 h day-length were studied in five wheat lines: the multispikelet line Noa, the regular line Mara, the F1 hybrid between them and monosomics 2D of Mara and of this hybrid (lacking the 2D chromosome of Mara). Noa had a longer spike development phase, a higher initial number of spikelet primordia and a slower rate of spikelet production than Mara. The F1 hybrid was similar to Noa in its high initial number of spikelets and to Mara in its high rate of spikelet production. This hybrid had a shorter spikelet phase than both parents. Deletion of one dose of the Mara 2D chromosome from either Mara or the F1 hybrid caused a reduction in the rate of spikelet production and an increase in the duration of the spikelet phase. These effects were due to the reduced dosage of the 2D chromosome. However, in the F1 hybrid this deletion also caused an increase in the spike development phase — an indication that Noa carries on its 2D chromosome a recessive gene for late heading date which acts on the spike development phase. This gene of Noa is independent of the day-length sensitive gene ppd, and is different from Noas dominant gene for large initial number of spikelets. 相似文献
5.
Werner Dangel Ruth Brackmann Achim Lack Magdy Mohamed Jürgen Koch Brigitte Oswald Birgit Seyfried Andreas Tschech Georg Fuchs 《Archives of microbiology》1991,155(3):256-262
The regulation of the expression of enzyme activities catalyzing initial reactions in the anoxic metabolism of various aromatic compounds was studied at the whole cell level in the denitrifying Pseudomonas strain K 172. The specific enzyme activities were determined after growth on six different aromatic substrates (phenol, 4-hydroxybenzoate, benzoate, p-cresol, phenylacetate, 4-hydroxyphenylacetate) all being proposed to be metabolized anaerobically via benzoyl-CoA. As a control cells were grown on acetate, or aerobically on benzoate. The expression of the following enzyme activities was determined.Phenol carboxylase, as studied by the isotope exchange between 14CO2 and the carboxyl group of 4-hydroxybenzoate; 4-hydroxybenzoyl-CoA reductase (dehydroxylating); p-cresol methylhydroxylase; 4-hydroxybenzyl alcohol dehydrogenase; 4-hydroxybenzaldehyde dehydrogenase; coenzymeA ligases for the aromatic acids benzoate, 4-hydroxybenzoate, phenylacetate, and 4-hydroxyphenylacetate; phenylglyoxylate: acceptor oxidoreductase and 4-hydroxyphenylglyoxylate: acceptor oxidoreductase; aromatic alcohol and aldehyde dehydrogenases.The formation of most active enzymes is strictly regulated; they were only induced when required, the basic activities being almost zero. The observed whole cell regulation pattern supports the postulate that the enzyme activities play a role in anoxic aromatic metabolism and that the compounds are degraded via the following intermediates: Phenol 4-hydroxybenzoate 4-hydroxybenzoyl-CoA benzoyl-CoA; 4-hydroxybenzoate 4-hydroxybenzoyl-CoA benzoyl-CoA; benzoate benzoyl-CoA; p-cresol 4-hydroxybenzaldehyde 4-hydroxybenzoate 4-hydroxybenzoyl-CoA benzoyl-CoA; phenylacetate phenylacetyl-CoA phenylglyoxylate benzoyl-CoA plus CO2; 4-hydroxyphenylacetate 4-hydroxyphenylacetyl-CoA 4-hydroxyphenylglyoxylate 4-hydroxybenzoyl-CoA plus CO2 benzoyl-CoA. 相似文献
6.
7.
Evrard JL Nguyen I Bergdoll M Mutterer J Steinmetz A Lambert AM 《Plant molecular biology》2002,49(6):611-620
We describe here a new -tubulin isoform from sunflower we named -tubulin. -tubulin is the most divergent higher-plant -tubulin described so far, having an unusual deletion in the H1/B2 loop and a glutamine-rich C-terminus. We constructed a three-dimensional model and discuss its implications. Using specific antibodies, we show that -tubulin expression is restricted to the male gametophyte. -tubulin mRNA represents 90% of -tubulin mRNA and a small percentage of total pollen mRNA. Among the plants tested, -tubulin was only detected in sunflower and in Cosmos. Since both plants are Asteraceae, we propose that -tubulin is specific to this family. Our results suggest that -tubulin can inhibit tubulin assembly in pollen. This hypothesis is reinforced by the fact that -tubulin is found in a complex with -tubulin in mature sunflower pollen. 相似文献
8.
W. Lange I. Linde-Laursen J. Larsen A. Ljungberg S. Ellerström 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(5):635-645
Summary The winter wheat varieties Starke and Cappelle Desprez and the spring wheat Chinese Spring were analysed for structural chromosome rearrangements that resulted in the formation of multivalents in F1 hybrids. The analyses were carried out using hybrids involving euploids, monosomic and ditelosomic stocks, and double-monotelodisomic constructs. The study confirmed that Cappelle Desprez differs from Chinese Spring in a reciprocal translocation between chromosomes 5B and 7B (Riley et al. 1967); a translocation involving chromosomes 3B and 3D could not be verified. Furthermore, the analysis showed that Starke differs from Chinese Spring in a reciprocal translocation between chromosomes 7A and 7D. Both translocations have a coefficient of multivalent realisation of about 0.84. Further multivalents in euploid Starke, in euploid and some aneuploid stocks of Cappelle Desprez, and in euploid as well as various types of aneuploid hybrids between all three varieties could nearly all be explained hypothesizing that chromosome 2B of both Starke and Cappelle Desprez is a duplication-deficiency chromosome. In the hypothesis a part of the long arm of 2B is missing and replaced by a duplicated part of the long arm of chromosome 2D. The multivalents of this rearrangement showed an average coefficient of realisation of about 0.09.Sven Ellerström died in December 1985 相似文献
9.
G. R. N. Jones 《Histochemistry and cell biology》1969,18(2):164-167
Summary The syntheses of 4,4-biphenyl tetrazonium chloride monohydrate, of 1,1-di-(3-nitrophenyl)-3,3-dimethyl-5,5-(4,4-biphenylene)-diformazan, and of yellow tetrazolium [2,2-di-(3-nitrophenyl)-5,5-dimethyl-3,3-(4,4-biphenylene)-ditetrazolium chloride] are described. Solutions of the pure formazan in pyridine absorb visible light maximally at 455 nm; 455 is 54,050. Yellow tetrazolium has been specifically designed to meet the requirement of a new technique in quantitative cytochemistry, which involves the consecutive use of two bistetrazolium salts on the same tissue section.I thank Professor L. Young of St. Thomas's Hospital Medical School and Professor C. Long of the Royal College of Surgeons for their interest and encouragement. I am greatly indebted to a large number of friends and colleagues for helpful discussion, and to Dr. A. Deavin and Miss A. Banks for exploratory experiments which involved column chromatography. Microanalyses were carried out by Mr. G. S. Crouch at the London School of Pharmacy. 相似文献
10.
An investigation of the role of solutes in the xylem sap and in the xylem parenchyma as the source of root pressure 总被引:7,自引:0,他引:7
Summary Solute osmotic potentials (x) in the vessels of hydroponically grown maize roots were measured to assess the osmotic-xylem-sap mechanism for generating root pressure (indicated by guttation). Solutes in vessels were measured in situ by X-ray microanalysis of plants frozen intact while guttating. Osmotic potentials outside the roots (o) were changed by adding polyethylene glycol to the nutrient solution. Guttation rate fell when o was decreased, but recovered towards the control value during 3–5 days when o was greater than or equal to –0.3 MPa, but not when o was equal to –0.4 MPa. In roots stressed to o = –0.3 MPa, x, was always more positive than o, and x changed only slightly (ca. 0.05 MPa). Thus the adjustment in the roots which increased root pressure cannot be ascribed to x, contradicting the osmotic-xylem-sap mechanism. An alternative driving force was sought in the osmotic potentials of the vacuoles of the living cells (v), which were analysed by microanalysis and estimated by plasmolysis. v showed larger responses to osmotic stress (0.1 MPa). Some plants were pretreated with abundant KNO3 in the nutrient solution. These plants showed very large adjustments in v (0.4 MPa) but little change in x (0.08 MPa). They guttated by 4 h after o was lowered to –0.4 MPa. It is argued that turgor pressure of the living cells is a likely alternative source of root pressure. Published evidence for high solute concentrations in the xylem sap is critically assessed.Abbreviations o
external water potential
- x
osmotic potential of xylem sap
- v
osmotic potential of vacuolar sap
- EDX
energy dispersive X-ray microanalysis
- CSEM
cryo-scanning electron microscope
- LN2
liquid nitrogen
- PEG
polyethylene glycol 相似文献
11.
G. P. Vlasov V. I. Korol'kov G. A. Pankova I. I. Tarasenko A. N. Baranov P. B. Glazkov A. V. Kiselev O. V. Ostapenko E. A. Lesina V. S. Baranov 《Russian Journal of Bioorganic Chemistry》2004,30(1):12-20
We attempted to find some compounds for the effective delivery of gene constructs into cells and obtained two trispherical dendrimers on the basis of lysine, (Lys)8-(,-Lys)4-(,-Lys)2-(,-Lys)-Ala-NH2 (D1) and ((Lys)8-(,-Lys)4-(,-Lys)2-,-Lys)-Ala-[Lys(Plm)]2-Ala-NH2 (D2), as well as the starburst polymeric derivatives of D1, (pVIm)
8
-D1 and (pLys)
n
-D1, containing poly(N-vinylimidazole) and polylysine chains single-point bound to the dendrimer amino groups. The conditions of dendrimer–plasmid DNA complex formation were studied. The intracellular localization of these complexes and the expression of gene constructs delivered with their help were analyzed in transfection experiments on the HeLa cell cultures of human epithelial carcinoma and on mouse C2C12 myoblasts. It was found that the chemical structure of dendrimer D1 and its derivatives significantly affected the structure and properties of complex. 相似文献
12.
Venil Naranan Debra A. Brickey Charles L. Rutherford 《Molecular and cellular biochemistry》1988,83(1):89-104
Summary The slime mold Dictyostelium discoideum has two forms of the enzyme glycogen phosphorylase. The inactive phosphorylase b form requires 5 AMP for activity and is present in early development. The active phosphorylase a form is 5 AMP independent and occurs during later development. We here show that the 92 kd b enzyme subunit exists either as a singlet or a doublet upon SDS-PAGE, depending on the method of sample extraction. In the presence of exogenously added Mn2+ and ATP, the phosphorylase b shows apparent conversion into a 5 AMP independent form as measured by enzyme activity. In addition, Mn2+ and ATP also support an in vitro phosphorylation of the 92 kd phosphorylase b subunit. We also demonstrate phosphorylation of the b enzyme subunit in vivo by 32-P incorporation into the enzyme protein. A protein kinase responsible for the observed in vitro phosphorylation of the phosphorylase b subunit is characterized. 相似文献
13.
R. Kaiser W. Friedt 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,77(2):241-245
Summary In order to localize a gene for resistance to Barley Yellow Mosaic Virus (BaYMV) of German resistant varieties, cvs. Ogra and Sonate were crossed to a complete trisomic (2n=2x+1=15) set of Shin Ebisu 16. Tests for resistance in F2 strongly support the conclusion that the German gene for resistance to BaYMV is located on barley chromosome 3. 相似文献
14.
Decroocq V. Hagen L.S. Favé M.-G. Eyquard J.-P. Pierronnet A. 《Molecular breeding : new strategies in plant improvement》2004,13(2):135-142
In a previous study, cDNA microsatellite markers were described in apricot (Prunus armeniaca L.). Specific PCR primers were designed to amplify the microsatellite-containing regions from genomic DNA in different Prunus species. In the present work, cDNA microsatellite markers were developed in the hexaploid Prunus domestica L. species and polymorphism was ascertained in a segregating plum population. Co-dominant mendelian segregation of alleles was demonstrated and microsatellite polymorphism displayed up to 6 alleles per SSR locus per individual. Parentage lineage of three full-sib European plum cultivars (cv. Cacanska najbolja, Cacanska rana and Cacanska lepotica) was reconstructed by the analysis of the above nuclear SSR markers, completed by four chloroplastic microsatellite loci. The six most informative nuclear loci enabled discrimination between the three Cacak cultivars and unrelated individuals as well as the previously proposed parents, Wangenheim and Pozegaca. Data obtained support previous evidence that these cultivars originated from the Stanley cultivar. However, SSR analysis finally excluded Wangenheim as the other possible parent. Based on the results obtained with nuclear and chloroplast SSR loci, we propose the origin of those three Cacak cultivars in a cross between Stanley as the mother plant and Ruth gerstetter as the pollinator. Furthermore, we demonstrate the utility of these apricot SSR markers for genotype fingerprinting of the hexaploid plum cultivars. 相似文献
15.
Summary The self-condensation of 2(3)-O-glycyl esters of adenosine, adenosine-5-(O-methylphosphate) and P1, P2-diadenosine-5-pyrophosphate in 6.2 mM solutions at pH 8.0 and -5°C in the presence of 12.5 mM poly(U) yields approximately 3 times as much diketopiperazine as reactions without poly(U). As the concentration of 2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate is decreased from 6.2 mM to 1.5 mM the yield of diketopiperazine in the presence of poly(U) decreases slightly from 6.6% to 5.2%, whereas, in the absence of poly(U) the yield of diketopiperazine decreases substantially from 2.4% to 0.75%. The enhanced yield of diketopiperazine that is attributed to the template action of poly(U) is temperature dependent and is observed only at temperatures below 10°C (5°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) and below 23°C (15°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate. The absence of a template effect at high temperatures is attributed to the melting of the organized helices. The hydrolysis half-lives at pH 8.0 and -5°C of 2(3)-O-(glycyl)-adenosine, 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate), 2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate, and 5-O-(glycyl)-adenosine in the presence of poly(U) are substantially larger than their half-lives in the absence of poly(U). The condensation of 2(3)-O-(glycyl)-adenosine yields 5% of 5-O-(glycyl)-adenosine in the presence of poly(U) compared to 0.7% in the absence of poly(U).Abbreviations DKP
diketopiperazine
- (gly)2
glycylglycine
- (gly)3
glycylglycylglycine
- AppA-gly
2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate
- MepA-gly
2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate)
- Ado-2(3)-gly
2(3)-O-(glycyl)-adenosine
- Ado-5-gly
5-O-(glycyl)-adenosine
- Boc-gly
N-tert-butyloxycarbonylglycine
- AppA
P1, P2-diadenosine-5-pyrophosphate
- MepA
adenosine-5-(O-methylphosphate)
- AppA-Boc-gly
2(3)-O-(Boc-glycyl)-P1, P2-diadenosine-5-pyrophosphate
- Ado-5-Boc-gly
5-O-(Boc-glycyl)-adenosine
- Ado-2(3)-Boc-gly
2(3)-O-(Boc-glycyl)-adenosine 相似文献
16.
Hubert Felle 《Planta》1981,152(6):505-512
In the aquatic liverwort Riccia fluitans, membrane depolarization (m), change in membrane conductance (gm), and current-voltage (I-V) characteristics in the presence of different amino acids as well as the uptake of 14C-labeled amino acids were measured. L-isomers of the tested amino acids generate larger electrical effects (m, gm) than D-isomers, and the I-V characteristics show that the positive electrical inward-current of 20 mA m-2 generated by 0.5 mM D-serine is only about 50% of the current generated by adding 0.5 mM L-serine. Whereas - and -amino acids rapidly depolarize the membrane to the same extend, with -aminobutyric acid (-AB) and dipeptides no significant electrical effects have been measured. The uptake kinetics of 14C-labeled amino acids display three components: (I) A saturable high-affinity component with Ks-values of 48 M D-alanine, 12 M -aminoisobutyric acid (AIB), 9 M L-alanine, 8 M L-proline, and 6 M L-serine, respectively; (2) an apparently linear low-affinity component, and (3) an also linear but unspecific component at concentrations >20 times the given Ks-value. Uptake of 14C-labeled AIB can be inhibited competitively by all tested neutral amino acids, the L-isomers being more effective than the D-isomers, as well as by ammonium or methylamine. Vice versa, AIB competitively inhibits uptake of L-serine and L-alanine. It is concluded that an uncharged stereospecific carrier for the investigated amino acids exists in the plasmalemma of Riccia fluitans. Accumulation ratios of about 50 suggest secondary active transport driven by a transmembrane electro-chemical gradient (mainly m) which is generated by the electrogenic proton pump. It is suggested that this carrier binds to the amino group forming either a charged binary complex with positively charged amines (Felle 1980), or an uncharged complex with -AB or dipeptides, whereas electrogenic transport of - and -amino acids is mediated by a ternary carrier complex, probably charged by a proton.Symbols and Abbreviations m
membrane potential (mV)
- Eco
equilibrium potential (mV) of the transport system
- gm
membrane (slope) conductance (Sm-2)
- gm
change in gm
- I-V curve
current-voltage curve
- AIB
-aminoisobutytric acid
- -AB
-aminobutyric acid 相似文献
17.
R. P. Singh R. A. McIntosh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(6):846-855
Summary Chris wheat possessed genes Sr5, Sr7a, Sr8a, Sr9g and Sr12. W3746, derived from the cross Chris/Baart, possessed Sr7a and Sr12. The response conferred by Sr7a was influenced by the genetic background. Although Sr7a or Sr12 alone conferred no observable resistance upon adult plants, the adult resistances of Chris and W3746 to predominant pathotypes appeared to be associated with the interaction of Sr7a and Sr12, or genes at closely linked loci. 相似文献
18.
The response of effective quantum yield of photosystem 2 (F/Fm) to temperature was investigated under field conditions (1 950 m a.s.l.) in three alpine plant species with contrasting leaf temperature climates. The in situ temperature response did not follow an optimum curve but under saturating irradiances [PPFD >800 µìmol(photon) m–2s–1] highest F/Fm occurred at leaf temperatures below 10°C. This was comparable to the temperature response of antarctic vascular plants. Leaf temperatures between 0 and 15°C were the most frequently (41 to 56%) experienced by the investigated species. At these temperatures, F/Fm was highest in all species (data from all irradiation classes included) but the species differed in the temperature at which F/Fm dropped below 50% (Soldanella pusilla >20°C, Loiseleuria procumbens >25°C, and Saxifraga paniculata >40°C). The in situ response of F/Fm showed significantly higher F/Fm values at saturating PPFD for the species growing in full sunlight (S. paniculata and L. procumbens) than for S. pusilla growing under more moderate PPFD. The effect of increasing PPFD on F/Fm, for a given leaf temperature, was most pronounced in S. pusilla. Despite the broad diurnal leaf temperature amplitude of alpine environments, only in S. paniculata did saturating PPFD occur over a broad range of leaf temperatures (43 K). In the other two species it was half of that (around 20 K). This indicates that the setting of environmental scenarios (leaf temperature×PPFD) in laboratory experiments often likely exceeds the actual environmental demand in the field.This revised version was published online in March 2005 with corrections to the page numbers. 相似文献
19.
Jacques Raymond Brahim Mimouni Jean-Louis Azanza 《Plant Systematics and Evolution》1994,193(1-4):69-79
The seed storage globulins from sixHelianthus and four hybrids were studied using mono and bidimensional gel SDS electrophoresis (+ 2 mercaptoethanol). The polypeptide composition of each subunit was determined. Different pairs are specifically expressed according to the species studied. Three typical patterns were discriminated. All the studied species exhibit five subunits: two of them are expressed in all the species (11 and 22). The subunit corresponding to the 11 pair is present inH. petiolaris and in the three populations ofH. annuus studied. The 2b2 pair is common toH. annuus andH. argophyllus. H. petiolaris presents two specific 2a2 and 44 pairs andH. annuus a specific 33 pair. InH. argophyllus 11 33 or 44 are never observed but are replaced by 13 and 31 pairs. Some globulins, poorly represented, are of forms but present chains of higher molecular weights (in the range 54–56 kDa). Expressing variations in the banding patterns between these species by the use of a similarity index reveals complete identity between the three populations ofH. annuus. Identity between the twoH. petiolaris studied is also observed.H. annuus andH. argophyllus appear to be closer to each other thanH. petiolaris concerning the seed storage globulins. 相似文献
20.
S. Nair J. S. Bentur U. Prasada Rao M. Mohan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(1):68-73
We have developed a polymerase chain reaction (PCR)-based assay that could effectively reduce the time period required to screen and select for Gall Midgeresistant rice lines under field conditions. The primers for the assay were designed on the basis of sequence information of two phenotype specific random amplified polymorphic DNA fragments which were found to be tightly linked to Gall Midge biotype-1 resistance gene (Gm2). The two RAPD fragments, F81700 in the susceptible parent ARC6650 and F10600 in the resistant parent Phalguna, were identified after screening 5450 loci using 520 random primers on genomic DNAs of ARC6650 and Phalguna. These primers, when used in a multiplexed PCR, amplified specifically a 1.7-kb and 0.6-kb fragment in the susceptible and resistant parents, respectively. When this assay was performed on genomic DNAs of 44 recombinant inbred lines derived from ARC6650 x Phalguna and 5 lines derived from other crosses where one of the parents was Phalguna, ARC6650 or their derivatives, the primers amplified a 1.7-kb fragment in all of the susceptible lines or a 0.6-kb fragment in all of the resistant ones. These markers can be of potential use in the marker-aided selection of Gall Midge biotype-1 resistant phenotypes. As screening for resistance can now be conducted independent of the availability of insects, the breeding of resistant varieties can be hastened. 相似文献