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1.
Growth analysis of plants raised under controlled environments(105, 12, 15, 18 and 20 °C, and 21 h photoperiod)was used to examine whether varietal differences in the minimumgermination temperature of four bean cultivars persist duringgrowth at suboptimal temperatures. A method to estimate theminimum vegetative growth temperature, based on axis relativegrowth rate, was developed. In order to compensate for ontogeneticdrift, the harvests were conducted at the same stage of developmentof the plants. Axis relative growth rates, reduction rates ofthe cotyledons and other growth parameters were calculated inorder to compare the cultivars. Cultivar Marschallshowed better growth potential at 12 °C than the others,Pergousa at 15 °C, and Marschall,Olsok and Pergousa at 18 and 20°C. The effect of temperature on axis RGR was similar forMarschall, Olsok and Pergousa(Q10 = 2·1) and more pronounced than for Processor(Q10 = 1·3). Although there were significant differencesin the growth parameters among the cultivars within each temperatureused, the differences did not correspond with the differencesduring germination at low temperatures. The minimum vegetativegrowth temperature was close to 10 °C for all the cultivarstested. Phaseolus vulgaris L., beans, suboptimum temperature, growth analysis, minimum germination temperature, minimum vegetative growth temperature 相似文献
2.
Flowering in two clones of Saccharum spontaneum L. is controlledby photoperiod. The earliest stages of development, inductionand initiation of the inflorescence axis primordium(IAP) were optimally promoted under intermediate days of 12h 30 min, while the subsequent stage initiation of inflorescencebranch primordia (IBP) was inhibited by days longer than13 h. The following stage initiation of spikelet primordia(ISP) showed a quantitatively intermediate response with anoptimum photoperiod of 9 h to 11 h. The elongation of the differentiatedinflorescence was found to be only slightly sensitive to photoperiodsof 13 h or longer in one of the clones. Unfavourable photoperiodsat stages following induction resulted in the arrest or delayof inflorescence development and when these were given duringthe IAP and IBP stages, reversion to the vegetative conditioncommonly occurred. 相似文献
3.
Plant Morphology: The Historic Concepts of Wilhelm Troll, Walter Zimmermann and Agnes Arber 总被引:1,自引:1,他引:0
Recent molecular systematic and developmental genetic findingshave drawn attention to plant morphology as a discipline dealingwith the phenotypic appearance of plant forms. However, sincedifferent terms and conceptual frameworks have evolved overa period of more than 200 years, it is reasonable to surveythe history of plant morphology; this is the first of two paperswith this aim. The present paper deals with the historic conceptsof Troll, Zimmermann and Arber, which are based on Goethe'smorphology. Included are contrasting views of unity anddiversity, position and process, and morphologyand phylogeny, which, in part, are basic views of currentplant morphology, phylogenetic systematics and developmentalgenetics. Wilhelm Troll established the type conceptand the principle of variable proportions. Hehas provided the most comprehensive overview of the positionalrelations of plant forms. Agnes Arber started from the universaldynamics of life and attempted to describe all structures asprocesses. She paid attention to repetitive branching,differential growth, and parallelism.As a result she has recently been rediscovered by developmentalbotanists. Walter Zimmermann rejected any metaphysical influenceon plant form and instead called for objective procedures. Hewas mainly interested in phylogenetic character transformationand the reconstruction of genealogical lines.Guided by the example of flower-like inflorescences, a futurepaper will deal with functional and developmental constraintsinfluencing plant forms. Recent morphological concepts (trialectical,continuum/fuzzy, processmorphology) will be discussed and related to currentmorphological and developmental genetic research. Copyright2001 Annals of Botany Company Plant form, plant morphology, natural philosophy, homology, phylogeny, Goethe, Troll, Arber, Zimmermann, typology, character transformation, differential growth, complementarity 相似文献
4.
p. 186, right column line 11 27.2 KBq change to37.2 MBq p. 187, left column line 8 27.2 KBq change to37.2 MBq line 10 13.6 KBq change to 18.6 MBq line 11 13.6 KBq change to 18.6 MBq line 21 89% change to 80% right column line 24 CLC-NH4 change to CLC-NH2 P. 189, Table 1 appeared incorrectly: it should appear as indicated. 相似文献
5.
The growing outer epidermal wall: design and physiological role of a composite structure 总被引:1,自引:0,他引:1
Kutschera U 《Annals of botany》2008,101(5):615-621
Background: The cells of growing plant organs secrete an extracellular fibrouscomposite (the primary wall) that allows the turgid protoplaststo expand irreversibly via wall-yielding events, which are regulatedby processes within the cytoplasm. The role of the epidermisin the control of stem elongation is described with specialreference to the outer epidermal wall (OEW), which forms a tensileskin. Novel Facts: The OEW is much thicker and less extensible than the walls ofthe inner tissues. Moreover, in the OEW the amount of celluloseper unit wall mass is considerably greater than in the innertissues. Ultrastructural studies have shown that the expandingOEW is composed of a highly ordered internal and a diffuse outerhalf, with helicoidally organized cellulose microfibrils inthe inner (load-bearing) region of this tension-stressed organwall. The structural and mechanical backbone of the wall consistsof helicoids, i.e. layers of parallel, inextensible cellulosemicrofibrils. These plywood laminates containcrystalline cables orientated in all directionswith respect to the axis of elongation (isotropic material).Cessation of cell elongation is accompanied by a loss of order,i.e. the OEW is a dynamic structure. Helicoidally arranged extracellularpolymers have also been found in certain bacteria, algae, fungiand animals. In the insect cuticle crystalline cutin nanofibrilsform characteristic OEW-like herringbone patterns. Conclusions: Theoretical considerations, in vitro studies and computer simulationssuggest that extracellular biological helicoids form by directedself-assembly of the crystalline biopolymers. This spontaneousgeneration of complex design without an intelligent designerevolved independently in the protective skin ofplants, animals and many other organisms. 相似文献
6.
Healthy tomato plants were shown to contain high levels of RNA-dependentRNA polymerase activity, mainly in a soluble form,but also partly in a bound form. The boundenzyme was solublized by EDTA treatment. Both forms of enzymewere partially purified and characterized. The ion and pH optimaof the two forms were identical at all stages of purification.Both enzymes exhibited uridylyl transferase activity, whichmade up 35 per cent of total incorporation. Infection with tobacco mosaic virus (TMV) increased activityof soluble enzyme by twofold, and of solubilizedbound enzyme by less than twofold. Uridylyl transferaseactivity was also increased by infection. General propertiesof the enzymes were unaltered by infection with one exception:in the presence of TMV RNA as added template, the solubleenzyme from infected plants incorporated 3H-UTP into productswith the electrophoretic properties and RNase sensitivitiesexpected for replicative form and replicative intermediate ofTMV. Soluble enzyme from healthy plants, and solublized bound enzyme from either healthy or infectedplants did not synthesize these products. The soluble and solubilized boundenzymes behaved differently on ion-exchange chromatography.Under the conditions used, soluble enzyme didnot bind to the column, whereas solublized boundenzyme did. No differences in chromatographic behaviour werefound between enzymes from healthy or infected plants. Withboth soluble and solublized boundenzymes, the uridylyl transferase activity co-chromatographedwith the polymerase activity. Tomato, Lycopersicon esculentum, RNA-dependent RNA polymerase, tobacco mosaic virus, tobacco mosaic virus replicase 相似文献
7.
《Journal of Molluscan Studies》1965,36(6):323
WARBURG, M. R., 1965. On the water economy of some Australianland snails. Proc. malac. Soc. Lond. 36, 297305. Page 298: second line from bottom, should read within± 1 µg for Themapupa. Page 300: Fig. 2 legend, should read Evaporative waterloss from Sinumelon remissum (a), Pleuroxia sp. (b) and Themapupaadelaidae (c). Page 300: section 4 heading, should read Continuous curvesfor water loss. Page 301: second line, for Fig. 9 read Fig.3. Page 301: Table 1, last line, for 0.120024 read0.12024. Present address: Israel Institute for Biological Research, Ness-Ziona,Israel. 相似文献
8.
Extracts of small and mature-size lupin pods yielded four substancesaffecting the growth of wheat-coleoptile sections: one acidpromotor (A), two acid inhibitors(B and X), and one neutralinhibitor(Y). Inhibitor B was extremely active, however, coleoptile sectionsshowed no signs of toxic effects; they resumed growth at a rapidrate after rinsing them and adding ß-indolylaceticand (IAA) to the medium. 1 µg of IAA was required to counteractthe effect of B extracted from 230 mg. Of tissue.On an equal fresh weight basis the inhibiting action of Bin lupin pods was 5001,500 times more potent than thatof inhibitor ß in etiolated pea seedlings. Small pods of plants infected with pea-mosaic virus yielded3 times the amount of A of healthy plants (equivalentto 1 µg. IAA 0.3 µg. IAA per 25 g. of tissue respectively),and approximately the amount of B. Mature podsof virus-infected plants again yielded moreA,but also 2? times more B than pods of healthyplants. Healthy pods yielded more A than virus-infectedpods, and there was no difference in X. A lupin abscission test was developed and the effects of proximaland distal application of -naphthyl acetic acid (NAA) are presented,and discussed with respect to results of other abscission tests. A accelerated abscission when applied proximally,and delayed or prevented it when applied distally. Bstrongly accelerated abscission when applied in either way.A possible mechanism explaining the abscission-inducing effectof developing pods on later flowers is discussed in terms ofthe substances A and B. The partlyprevented abscission observed on virus-infected plants was foundto agree well with the proposed mechanism. 相似文献
9.
When nitrate, ammonium, or urea were the sole nitrogen sourcesfor the growth of Platymonas striata there was a short initiallag period, after which uptake/assimilation occurred at a constantrate. Glycine uptake was however non-linear withtime. Addition of ammonium or urea markedly inhibited nitrateuptake whereas although glycine was initiallytotally inhibitory, nitrate uptake recommencedabout 1 h after addition, but at a greatly reduced rate. Ammoniumtotally inhibited urea uptake, but did not inhibitglycine uptake. When ammonium, urea, or glycinewere present at the same time as nitrate the total rate of nitrogen'uptake/assimilation was within 40% (or closer) of that of nitratenitrogen uptake alone. In the first two casesthis reflected a total switching off of nitrate uptakewhilst the new substrate was assimilated at a rate similar tothe initial nitrate rate, whereas in the case of glycine, bothsubstrates were used simultaneously. Once the concentrationof any of the inhibitory nitrogen sources had been reduced toa low level the uptake/assimilation of nitraterecommenced. It is suggested that the ability of P. striatato maintain a more or less constant rate total nitrogen uptake/assimilationirrespective of the mixture of utilizable nitrogen sources presentedto it, is not due to controls at the level of the entry of substrateinto the cell, but to intracellular actions at the enzyme level.The relative constancy of, and high rate of uptake,irrespective of nitrogen source and over a wide range of extracellularconcentrations, is tentatively considered to be due to saturationof the assimilatory mechanisms under the conditions employed;all the sources lead, either directly or indirectly, to theproduction of amino groupings for entry into nitrogenous metabolism.This homeostasis of nitrogen uptake/assimilationwould clearly be of considerable benefit to the alga in nature,enabling it to maximize growth in changing environmental conditions. Platymonas striata, nitrogen update, nitrogen assimilation 相似文献
10.
A preliminary study of four bambusoid, three arundinoid, l0pooid, 16 chloridoid and 26 panicoid grasses, coupled with datafrom previous studies reveal that, in addition to the relativesize and structure of the mature embryo reported by Reeder (1957,1962), taxa belonging to the subfamilies Pooideae and Panicoideaealso possess contrasting characters in respect to the shapeof ovary, structure of dorsal ovary wall, extent of developmentof integuments, behaviour of the nucellar epidermis in the vicinityof the micropyle, orientation of the mature megagametophytein relation to the longitudinal axis of the ovule, constitutionof the unreduced megagametophytes in apomictic taxa, shape ofthe embryo sac during free nuclear stages of endosperm, positionof the antipodals in the embryo sac after fertilization, anddifferentiation in the inner epidermis of the inner integumentafter fertilization. These characters may also be typed as eitherpooid or panicoid in nature. Thepooid features exhibit a higher frequency in grassesof the subfamilies Bambusoideae, Arundinoideae and Chloridoideae.The panicoid features are predominant in grassesof the subfamily Panicoideae. Embryology, systematics, gramineae 相似文献
11.
Mitochondria from 1-day-old bean cotyledons were isolated bya slow isolation procedure involving a wash andby a rapid procedure. The mitochondria isolatedby the rapid procedure were more tightly coupledthan those isolated by the slow procedure. Anexogenous supply of cytochrome c or NAD was shown to improvethe activity of mitochondria isolated by the slowprocedure, but not those isolated by the rapidprocedure. The phosphorylative abilities of the latter weremuch greater than the former and were retained for longer periods.It was found that there was a leakage of NAD out of the mitochondria. 相似文献
12.
13.
Angioy Anna M.; Barbarossa Iole Tomassini; Liscia Anna; Usai Maria L.; Orru Sergio; Muroni Patrizia; Crnjar Roberto 《Chemical senses》1990,15(2):145-150
Stimulation of single largest or marginallabellar chemosensilla can evoke ipsi- and contralateral labellarlobe spreading responses in Protophormia. Measurements of reflexlatencies indicate that the response is triggered by messagescoming from the largest ipsilateral chemosensilla.Input from the marginal chemosensilla would playa role in maintaining the already triggered response. 相似文献
14.
Diurnal laminar reorientation was followed in solar-trackingleaves of Lavatera cretica L. under simulated conditions. Asimulated sun was moved over the lamina in a 180?arc in the vertical plane of the mid-vein, at an angular velocityof 15? h1 in a regime of 12-h photoperiods. In one groupof plants the petioles of the experimental leaves were arrangedto face sunrise, while in the other they werearranged to face sunset. At sunrise,the laminae in both groups, which were inclined towards theanticipated direction of sunrise, changed theirelevation towards the rising sun, resulting inprogressive reduction in the angle of incidence (AI) of lighton the laminar surface (AI= differential between laminar andsolar elevation). As a result, laminar and solarelevation converged, and laminar reorientation gradually ceased,until the solar elevation had passed the normalto the laminar surface (AI=0?). laminar reorientation was thenresumed, but its direction was reversed to follow the directionof solar reorientation. During most of the remainingday, laminar elevation (LE) trailed that of thesun by an average of 11?-14?. Laminar reorientationthen anticipated sunset by starting to slow down60 to 90min in advance. During the 12-h dark period, the laminareoriented towards the anticipated direction of the subsequentsunrise. The time-course of nocturnal reorientationwas qualitatively different in the two groups of experimentalplants. The time-course of diurnal phototropism under naturaland simulated conditions is analysed and compared and differencesand similarities between them are discussed. Key words: Diurnal phototropism, solar-tracking, vectorial excitation 相似文献
15.
Effect of Source of Nitrogen on the Growth of Fiskeby Soya Bean: the Carbon Economy of Whole Plants 总被引:1,自引:0,他引:1
Fiskeby V soya bean was grown from seed germination to seedmaturation with two contrasting patterns of nitrogen metabolism:either wholly dependent on dinitrogen fixation, or with an abundantsupply of nitrate nitrogen, but lacking root nodules. The carbonand nitrogen economies of the plants were assessed at frequentintervals by measurements of photosynthesis, shoot and rootrespiration, and organic and inorganic nitrogen contents. Plantsfixing atmospheric nitrogen assimilated only 2530 percent as much nitrogen as equivalent plants given nitrate nitrogen:c. 40 per cent of the nitrogen of nitrate plantswas assimilated after dinitrogen fixation had ceased in nodulatedplants. The rates of photosynthesis and respiration of the shootsof soya bean were not markedly affected by source of nitrogen;in contrast, the roots of nodulated plants respiredtwice as rapidly during intense dinitrogen fixation as thoseof nitrate plants. The magnitude of this respiratoryburden was calculated to increase the daily whole-plant respiratory loss of assimilate by 1015 per cent over thatof plants receiving abundant nitrate. It is concluded that nodulatedplants grew more slowly than nitrate plants inthese experiments for at least two reasons: firstly, the symbioticassociation fixed insufficient nitrogen for optimum growth and,secondly, the assimila tion of the nitrogen which was fixedin the root nodules was more energy-demanding in terms of assimilatethan that of plants which assimilated nitrogen by reducing nitratein their leaves. 相似文献
16.
The metabolic fate of [U-14C]sucrose in suspension culturesof Catharanthus roseus cells was monitored for 96 h after thecells were transferred to fresh complete (+Pi)or to phosphate-deficient Murashige and Skoog (Pi)medium. Sucrose was hydrolysed extracellularly to glucose andfructose. The rate of uptake of sugars by the cells was 1.53times higher in +Pi culture than in Piculture. Little difference in the rate of incorporation of radioactivityinto the ethanol-soluble fraction was found between the +Piand Pi cultures during the initial 24h of culture, but after 48 h the rate in +Picultures was higher than that in Pi cultures.Incorporation of radioactivity into ethanol-insoluble macromoleculeswas always significantly higher in the cells in +Picultures than in those in Pi cultures.The results suggest that Pi strongly affects the utilizationof sugars by cultured plant cells through the stimulation oftransport of sugars as well as through the activation of metabolism. Catharanthus roseus, Madagascar periwinkle, suspension culture, inorganic phosphate, sucrose, transport, metabolism 相似文献
17.
《Journal of experimental botany》1977,28(6):1247
Effects of coupled solute and water flow in plant roots withspecial reference to Brouwer's experiment. Edwin L. Fiscus. p. 71 Abstract: Line 3 delete interval insertinternal. p. 73 Materials and Methods: line 6: delete diversion insert division line 9 equation should read Jv=Lp PRT(C0C1). 74 Last line of figure legend: 101 should read 1011. 75 Line 11: delete seems insert seem. le 1 column heading106 should read 1011. 77 delete ...membrane in series of... insert membranein series or... Delete final paragraph. 相似文献
18.
SHEWRY P. R.; FIELD J. M.; KIRKMAN M. A.; FAULKS AUDREY J.; MIFLIN B. J. 《Journal of experimental botany》1980,31(2):393-407
This paper reports further studies on the characteristics ofthe storage protein fraction (hordein) of barley. Hordein consistsof two groups of polypeptides (termed B and C)coded by two separate but linked loci. Whereas the Cpolypeptides are readily soluble and extracted in 60% (v/v)ethanol at room temperature, the B group is moresoluble in, and therefore more efficiently extracted by, 50%(v/v) propan-1-ol or 45% (v/v) propan-2-ol at elevated temperaturesand in the presence of 2-mercaptoethanol. However, the mostefficient conditions for hordein extraction (50% propan-1-ol+ 2% (v/v) 2-mercaptoethanol at 60 °C) also extract somecontaminating non-hordein polypeptides resulting in an apparentlyincreased lysine content of the hordein fraction. Amino acid analysis of the purified B and Chordein groups shows that, whereas C hordein containsmore glutamate + glutamine, proline, and phenylalanine thanB hordein, it contains only traces of lysine andsulphur amino acids in contrast to B hordein whichcontains 0·5% lysine 0·6% methionine, and 2·5%cysteine. Equilibrium sedimentation analyses carried out on the purifiedB and C groups indicates that thepreparations were reasonably monodisperse with molecular weightsof approximately 32 000 and 52 000 respectively. These valuesare considerably lower than those previously determined by SDS-PAGE. 相似文献
19.
《Journal of experimental botany》1981,32(2):293
Page 806, Preparation of Mitochondrial Fraction, line 4: The following should be inserted between centrifugedat and 20 000 g for: 3000 for 10 mm. Thesupernatant was centrifuged at The following corrections are required: Page 104, line 20: 2-hydroxylation should read 2-ß3-hydroxylation Page 106, line 11: of Ga8 should read to GA8 Page 113, last line:length 50 µm shouldread length 150 µm Formula 15 should read:
Formula 17 should read: y(0) y* = ß1V1+ß2V2 page 118: Formula 18 should read:
Formula 23 should read:
Formula 24 should read:
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20.
Subjects from Britain and America were tested on their skillat applying the taste adjectives sweet, sour,salty, and bitter to clearly distinguishablesolutions of sucrose, citric acid, NaCl and quinine sulphate,respectively. The main error that occurred was calling citricacid bitter while the tendency to call quininesulphate sour was not so common; this is the wellknown sour-bitter confusion. A sour-salty confusion was alsonoted as well as a tendency to call citric acid sweet.All these confusions were rectified by mere definition usingstandards. Skill at applying taste adjectives was not alwaysfound to be consistent over time. More errors occurred at lowersolution concentrations, even though stimuli were clearly distinguishable;indistinguishability of stimuli may account for some confusionsin other studies.
*Present address: Department of Psychology, University of Bristol,Bristol BS8 1HH, England. 相似文献