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1.
The nucleic acid, protein and uncombined amino acid contentof seeds of soya-bean (Glycine max L. Merr.), garden pea (Pisumsativum L.), kidney bean (Phaseolus vulgaris L.) and peanut(Arachis hypogaea L.) were measured at various times duringseed formation in an effort to understand why the soya-beanhas nearly twice as much protein as the other legume seeds.In all these species the concentration of deoxyribonucleic acid,ribonucleic acid and uncombined amino acids decreased duringseed formation. The protein level of kidney bean was relativelyconstant during development whereas the protein levels of pea,peanut and soya-bean increased during development. The proteincontent of the soya-bean increased throughout development whereasthe protein increase in peanut took place early and that inpea took place later in development. The ratio of protein toribonucleic acid was highest in peanut, less in soya-bean, andlowest in pea and kidney bean. Similarly, the ratio of proteinto deoxyribonucleic acid was higher in kidney bean than in soya-bean.Soya-beans had a lower amino acid content than any of the otherseeds at all stages of development. These results indicate thatneither total deoxyribonucleic acid, ribonucleic acid nor uncombinedamino acid content is responsible for the higher protein contentof soya-beans.  相似文献   

2.
McCOMB  A. J. 《Annals of botany》1965,29(3):445-458
Gibberellic acid (GA) was found to stimulate internode expansionin floating rosettes of the aquatic, Callitriche stagnalis.Treated shoots resembled those normally produced from submergedapices. The environmental factor which controls the growth ofuntreated floating rosettes was investigated, and found to beloss of water by transpiration. The morphological effects ofdifferent concentrations of GA are described. The similarityis pointed out between environmental dwarfing in Callitricheand genetic dwarfing in Pisum.  相似文献   

3.
Horizontal starch gel electrophoresis has been applied to thestudy of esterase, peroxidase and acid phosphatase patternsin seven taxa, namely Hordeum diploids (2n=14) (H. marinum,H. marinum I and H. hystrix), tetraploids (2n=28) (H. bulbosumand H. murinum subsp. leporinum) and Taeniatherum (2n=14) (T.caput-medusae and T. caput-medusae I) in order to elucidatetheir phylogenetic relationships. On the basis of our experimentalresults the seven taxa may be placed in the following threegroups; (1) diploid Hordeum (H. marinum, H. marinum I, H. hystrix);(2) tetraploid Hordeum (H. bulbosum, H. murinum subsp. leporinum);(3) Taeniatherum (T. caput-medusae, T. caput-medusae I). Esterase, peroxidase and acid phosphatase patterns of the twoHordeum diploid taxa (H. marinum and H. marinum I) are verysimilar suggesting their close phylogenetic relationship; thesame is true for both the taxa of the genus Taeniatherum (T.caput-medusae and T. caput-medusae I). The taxa of the Taeniatherumgroup compared with the diploid Hordeum (H. marinum, H. marinumI, H. hystrix) and the tetraploid Hordeum (H. bulbosum, H. murinumsubsp. leporinum) show a lower degree of phylogenetic relationshipand seem to be equally distant from them. The tetraploid Hordeumgroup shows a higher phylogenetic relationship with diploidHordeum group than with the Taeniatherum group. These results confirm that the genus Taeniatherum, previouslyconsidered as part of the genus Hordeum, should be regardedas a separate genus. Gramineae (Poaceae), Hordeum L., Taeniatherum Nevski., esterase, peroxidase and acid phosphatase patterns, phylogenetic relationships  相似文献   

4.
The agravitropic nature of root growth of an auxin-resistantmutant of Arabidopsis, auxl, was restored when the syntheticauxin 1-naphthaleneacetic acid (NAA) was added to the growthmedium; auxl roots were not resistant to NAA. Neither indole-3-aceticacid nor 2,4-dichlorophenox-yacetic acid had the same effectsas NAA. These differential effects of the three auxins on auxldefects suggest that AUX1 may encode the auxin influx carrieraccording to the model proposed by Oelbarre et al. [(1996) Planta198: 532]. 1To whom correspondence should be addressed. Fax: + 81-11-706-2253.e-mail: kty{at}ees.hokudai.ac.jp  相似文献   

5.
Acid phosphatase activity was present in unimbibed barley seed,but rose during incubation of embryoless half-seeds and isolatedaleurone layers, and was further increased by 10–6 M gibberellicacid (GA3). Release of total acid phosphatase activity fromhalf-seeds and aleurone layers was markedly enhanced by GA3.Inhibitor studies with cycloheximide and actinomycin D suggestedthat de novo synthesis of acid phosphatase occurred followingimbibition. Gel nitration, electrophoresis, and [14C]leucineincorporation studies revealed that a single molecular formof acid phosphatase was present in dry seed, whereas on incubationtwo further forms arose. A proportion of the three molecularforms of the enzyme was synthesized de novo. Gibberellic acidstimulated activation, but not de novo synthesis, of all threemolecular forms of acid phosphatase. Although a small amountof one of the molecular forms was secreted in the absence ofGA3, the presence of gibberellin greatly increased secretionof the same form of acid phosphatase.  相似文献   

6.
Three types of petrified filician rhizomes and their associatedpetioles and roots from the Rajmahal Hills, Bihar, India aredescribed. Two rhizomes possess protostelic vasculature withmesarch protoxylem elements and exarch protoxylem points. Theformer are gleicheniaceous while the latter is described asa schizaeaceous rhizome. The associated petioles possess typicalgleicheniaceous anatomy while the roots show variations in thestructure of epiblema and cortex. filician fossils, Jurassic, Actinostelopteris pakurense, Gleichenia sonajoriense, Solenostelopteris jurassica, Gleichenioamyelon diarcha, Filicoamyelon cryptogrammoides Filicoamyelon actinostachyoides  相似文献   

7.
Neill, S. J., McGaw, B. A. and Horgan, R. 1986. Ethylene and1-aminocyclopropane-l-carboxylic acid production in flacca,a wilty mutant of tomato, subjected to water deficiency andpretreatment with abscisic acid —J. exp. Bot. 37: 535–541. Plants of Lycoperstcon esculentum Mill. cv. Ailsa Craig wildtype and flacca (flc) were sprayed daily with H2O or 2?10–2mol m–3 abscisic acid (ABA). ABA treatment effected apartial phenotypic reversion of flc shoots; leaf areas wereincreased and transpiration rates decreased. Leaf expansionof wild type shoots was inhibited by ABA. Indoleacetic acid (IAA), ABA and l-aminocyclopropane-l-carboxylicacid (ACC) concentrations were determined by combined gas chromatography-massspectrometry using deuterium-labelled internal standards ABAtreatment for 30 d resulted in greatly elevated internal ABAlevels, increasing from 1?0 to 4?3 and from 0?45 to 4?9 nmolg–1 fr. wt. in wild type and flc leaves respectively.Endogenous IAA and ACC concentrations were much lower than thoseof ABA. IAA content ranged from 0?05 to 0?1 nmol g–1 andACC content from 0?07 to 0?24 nmol g–1 Ethylene emanationrates were similar for wild type and flc shoots. Wilting of detached leaves induced a substantial increase inethylene and ACC accumulation in all plants, regardless of treatmentor type. Ethylene and ACC levels were no greater in flc leavescompared to the wild type. ABA pretreatment did not preventthe wilting-induced increase in ACC and ethylene synthesis. Key words: ABA, ACC, ethylene, wilting, wilty mutants  相似文献   

8.
The activity of photosynthesis and mitochondrial respiration,nocturnal organic acid accumulation and water relations wereinvestigated in Prenia sladeniana L. Bol. [malic enzyme (ME)-type]andCrassula lycopodioides Lam. [phosphoenolpyruvate carboxykinase(PEPCK)-type] to compare the physiological responses to waterdeficit in crassulacean acid metabolism (CAM) plants differingin their decarboxylating enzyme systems. Withholding water inhibiteddaytime gas exchange within 2 d while night time CO2gain andmalic acid accumulation remained relatively unchanged in bothspecies. In P. sladeniana, maximum photochemical efficiency(Fv/Fm) and photosynthetic electron transport declined to nearlythe same degree as CO2supply was restricted during drought.Despite limited CO2availability, photosynthetic activity waslargely unaffected in C. lycopodioides, as were mitochondrialproperties. There is no indication of a drought-induced increasein the capability to totally oxidize malate, yielding 4 CO2, in either species. Nevertheless, the enhanced ratio of malateto glycine oxidation may have increased the in vivo capabilityfor malate oxidation in P. sladeniana. Although pressure potentialwas maintained throughout the experiment in both species, activeosmotic adaptation occurred only inP. sladeniana. The observeddecrease in photosynthetic and mitochondrial activity may haveresulted from the large increase in osmotic concentration inthis species. Copyright 2000 Annals of Botany Company Chlorophyll fluorescence analysis, Crassula lycopodioides Lam., crassulacean acid metabolism, citric acid, gas exchange, malic acid, mitochondria, photosynthetic electron transport, Prenia sladeniana L. Bol., water relations  相似文献   

9.
Root and Shoot Growth of Plants Treated with Abscisic Acid   总被引:4,自引:0,他引:4  
Young seedlings of Capsicum annum L., Commelina communis L.and maize (Zea mays L.) were subjected to a mild water-stressingtreatment and/or treated with abscisic acid (ABA). Plants rootedin soil received a soil-drying treatment and their leaves weresprayed with a 10–4 M solution of ABA. Plants grown insolution culture were stressed by the addition of polyethyleneglycol (PEG) to the rooting medium and ABA was also added tothe rooting medium, either with or without PEG. The effectsof both treatments on the growth of roots and shoots and theultimate root: shoot dry weight ratio were very similar. Shootgrowth was limited both by water stress and by ABA application;while there was some evidence that mild water stress and/orABA application may have resulted in a stimulation of root growth.More severe water stress reduced the growth of roots but theoverall effect of stress was to increase the ratio of rootsto shoots. Capsicum annum L., Commelina communis L., Zea mays L., water stress, abscisic acid  相似文献   

10.
Salicylic Acid Levels in Thermogenic and Non-Thermogenic Plants   总被引:7,自引:0,他引:7  
The natural trigger for heat production in the thermogenic inflorescencesof Sauromatum guttatum Schott (voodoo lily) was recently identifiedas salicylic acid (SA), which induced heat production at levelsas low as 13 ng g f. wt–1. Since then the levels of SAwere determined in other thermogenic and non-thermogenic plantspecies. In thermogenic inflorescences of five aroid species,and in male cones of at least four thermogenic cycads SA levelsduring heat production exceeded 1 µg g f. wt–1.SA was not detected in the thermogenic flowers of a water lily,Victoria regia Lindl. (Nymphaeaceae), and Bactris major Jacq.(Palmae). Levels of salicylic acid varied substantially in thefloral parts of seven non-thermogenic species and in the leavesof 27 non-thermogenic species. Amorphophallus campanulatus Blume ex Decne, Arum italicum Mill., Arum dioscoridis Sibth. & Son., Philodendron selloum Koch, Monstera deliciosa Liebm., Encephalartosferox Bertol. f., Encephalartos hildebrandtii A. Br. & Bouché, Encephalartos gratus Prain, Dioon edule Lindl. cv. edule, Dioon edule Lindl. cv angustifolium, Sauromatum guttatum Schott, voodoo lily, Victoria regia Lindl., Bactris major Jack, salicylic acid, thermogenicity, heat production  相似文献   

11.
Stentor is a heterolrich ciliate which often forms lawn-likecovers on the bottom and/or blooms in the pelagial of lakesworldwide. The species involved in these spectacular eventswere usually either not determined or misidentified becausethe keys are outdated and incomplete. Thus, we have revisedthe nominal species described since the first major revisionby Ehrenberg (1838). Main species characteristics are the presence/absenceof symbiotic algae, the shape of the macronucleus and the colourof the cortical pigment granules. The last character mentionedmust be studied in live cells because the pigment bleaches inchemically fixed specimens. Nineteen valid species are recognizedand dichotomously keyed according to these characteristics.Twenty-seven other species and varieties, described after Ehrenberg'srevision, are synonyms or species indeterminata A new species.S.araucanus, is described from South American lakes. It is asmall, broadly trumpet-shaped Stentor with symbiotic algae,vermiform macronucleus and blue-green cortical granules. Stentoraraucanus is probably euplanktic and restricted to the southernhemisphere. Stentor auriculalus Kahl. 1932 sensu Wang (1934)is recognized as a new species, Condylostoma wangi, and transferredto the genus Condylostoma. New nomenclatural corrections: Stentorbaicalius nom. nov. (pro S.pygmaeus, preoccupied). S loricatiisnom. corr. (for S.loricata), S.ruber nom. corr. (for S.ruhra).  相似文献   

12.
Flowering in the genus Spirodela, whether in the laboratoryor in nature, has been observed only rarely. In this communication,the growth and flowering behaviour of a local isolate of S.polyrrhiza, strain SP20, is being reported. The presence ofa chelate, such as EDTA, is obligatory for satisfactory vegetativegrowth of S. polyrrhiza SP20- An optimal flowering responseis obtained, however, only when compounds such as EDDHA, a phenolicanalog of EDTA, or benzoic acid are supplied. Flowering, soinduced, is not influenced by the length of the photoperiod.Flowering fronds become gibbous and both EDDHA and benzoic acidalso enhanced anthocyanin content. This investigation has also revealed that salicylic acid, whichis known to have chelating properties itself, induces floweringin this duckweed only in the simultaneous presence of EDTA,in the nutrient solution. (Received January 14, 1986; Accepted May 10, 1986)  相似文献   

13.
Monthly samples of L. australis, V. spongiartum, P. bicolorand D. cuneata were collected over a period of 12 months fromPrincess Royal Harbour, Western Australia. Preliminary informationon densities and biomass is given. Gonad histology points toseasonal reproductive cycles with autumn spawning in P. bicolorand D. cuneata and irregular spawning in V. spongiantm and L.australis. However, L. australis did show two peaks of larvalbrooding in the study period. Length-frequency data are discussedin the light of the proposed reproductive patterns for the fourspecies. Allometric relationships between length and both heightand width for all species are described and their value to eachspecies assessed. Populations of L. australis from differenthabitats show significant differences in shell shape. (Received 27 June 1983;  相似文献   

14.
COLE  M.; WOOD  R. K. S. 《Annals of botany》1961,25(4):417-434
The rate at which the fungi grew through apples was determinedin various ways and used to estimate their rate of linear advance.Five fungi were studied;they were Sclerotinia fructigena (firm-browncoloured rot, rapid growth through apples), Botrytis cinerea(soft, light-brown coloured rot, rapid growth through apples),Psyrenochaeta furfuracea (firm to soft rot, variable in colourbut generaly dark, slow growth through apples), Penicilliumexpansion A (soft, white rot, slow growth through apples) andPenicillium expansum B (soft, white rot, medium rate of growththrough apples). S. fructigena which had the highest rate oflinear advance which was about three times that of P. furfuraceawhich had the lowest. Methods for extracting different types of pectic substancesfrom sound and rotted tissues are described, and details aregiven of a rapid and reasonably accurate colorimetric methodof determining the anhydrogalacturonic acid content of theseextracts. The firm-rot fungi reduced the water-insoluble pecticsubstances by 10–20 per cent., but the soft-rot fungicaused much larger changes, up to 70 per cent. being degraded,The firm-rot and soft-rot fungi had different effects on thepectic substances insoluble in dilute acid but soluble in dilutealkali. The soft-rot fungi had little effect on these substances,or reduced their concentration, whereas the firm-rot fungi causedsubstantial increases compared with sound tissue. These resultsare considered in terms of pectic enzyme activity. Analysisof extracts by paper chromatography showed that galacturonicacid, absent from sound tissue, was present in each type ofrotted tissue. Di- and tri-galacturonic acids were present inrots caused by P. expansum, and these rots probably also containedproducts from the break-down of other polysaccharides.  相似文献   

15.
16.
The pleiotropic effects of three genetically related dwarfinggenes were investigated in near-isogenic lines of wheat. TheNORIN 10 semi-dwarfing alleles, Rht 1 and Rht 2, and the TomThumb allele, Rht 3, were assessed for effects on some vegetativemorphological and physiological characters. The Rht allelesaffected leaf size with a resultant decrease in leaf area ofthe whole plant. Rht 3, which had the most marked effects, reducedleaf area in young plants by as much as 30 per cent. Althoughflag leaf dimensions and stomatal distributions of the flagleaf were altered, the gene had no effect on its area, stomatalconductance or net CO2 exchange rate. Comparisons of Rht andtall plants revealed no differences in the abscisic acid (ABA)levels of either turgid or partially dehydrated leaves. Triticum aestivum L., wheat, dwarfing genes, leaf structure, abscisic acid, stomatal conductance, CO2, exchange, relative growth rate  相似文献   

17.
李后魂  王淑霞 《昆虫学报》2002,45(2):230-233
研究了中国模尖蛾属Meleonoma Meyrick,其中记述2新种:面模尖蛾 M. facialis Li et Wang, sp. Nov. 和软颚模尖蛾 M. malacognatha Li et Wang, sp. Nov.。绘制了雌雄外生殖器特征图,给出了中国模尖蛾属分种检索表。模式标本保存在南开大学生物系标本室。  相似文献   

18.
Stem cuttings of Chrysanthemum morifolium Ram. were treatedwith aqueous solutions of (2-chloroethyl)phosphonic acid (Ethrel)and indolebutyric acid (IBA). Ethrel (1 mg per 1) as a dip oras two foliar sprays, promoted root length and branching inMrs. Roy and Clipper which are difficult-to-root cultivars,but had no effect on Improved Mefo, an easy-to-root cultivar.IBA increased root number in both Clipper and Improved Mefo.The results suggest that IBA and Ethrel act at different stagesof the rooting process, with IBA promoting initiation and Ethrelstimulating elongation and branching. Increases in root numberwith IBA treatment, and in root length with Ethrel treatment,were accompanied by decreases in the soluble carbohydrate concentration,particularly in stem bases.  相似文献   

19.
The major isoenzymes of -mannosidase (EC 3.2.1.24 [EC] ) and ß-galactosidase(ECf 3.2.1.23 [EC] ) have been separated from cotyledons of gardenpea, Pisum sativum L. (Vicieae), chick pea, Cicer arietinumL. (Cicereae), and cowpea, Vigna unguiculata (L.) Walp. (Phaseoleae).Some of their properties have been determined, including pHoptima, Km values for p-nitrophenyl glycosidc substrates, andthe effects of several inhibitors. Swainsonine, an indolizidinealkaloid, was the most effective inhibitor of mannosidase 1,with I30 values of 5.6 x 10–8 M (cowpea), 1x 10–7M (chick pea) and 2.9 x 19–7 M (pea). The most effectiveinhibitor of ß-galactosidase 2 from all sources wasD-galactonic acid-1,4-lactonwe (-lactone), with Ki values rangingbetween 3.0 and 3.9x 10–3 M. An inhibitor of the E. coliß-galactosidose, p-aminophenyl thio-ß-D-galactopyranoside,did not inhibit any of the legume ß-galctosidases;rather it enhanced the activites of the enzymes from chick peaand cowpea cotyledons. Etiolated hull and seed tissues frompea pods developing in darkness contained similar acid glycosidaseactivities to normal green tissues, thus the chloroplast isan unlikely location for ß-galactosidase 2. The majorß-galactosidasesdetected with an indigogenic substrate (5-bromo-4-chloro-3-indoxyl-ß-D-galactopyranoside)following gel electrophoresis of extracts from pea hull, seedcoats and cotyledons appeared to be different from ß-galactosidase2. Acid glycosidase, cotyledon, isoenzyme, -lactone, legume, swainsonine  相似文献   

20.
The planktonic rotifer Ascomorpha ovalis feeds on large dinoflagellates(e.g. Ceratium sp., Peridinium sp.) and is able to extract theircell contents by means of its virgate mastax. This paper presentsthe results of experiments on the feeding behaviour of laboratory-culturedAscomorpha with Cerarium furcoides as food algae. Ascomorphaare three times larger than their prey Ceratium (by volume),but with regard to total length, their prey was even 20% larger.Ascomorpha showed a hyperbolic functional response curve witha plateau of the feeding rate at 8 Ceratium cells animal–1dar–1 when concentrations of Ceratium were >100 cellsml–1. The mean handling time (time for capturing and extractingone Ceratium cell) was 3 min. The shape of the functional responsewas better described by a curvilinear model than by a rectilinearmodel. However, handling times cannot be responsible for this,since they were too short to set limits on ingestion rates.At low food concentrations, encounter rates with prey seemedto limit the feeding rates of Ascomorpha, whereas at mediumto high food concentrations, Satiation effects (lower attackrates) seemed to set limits on the feeding rates. Ascomorphashowed a significant decrease in the exploitation of singleCeratium cells at high prey concentrations. This decrease couldbe explained by a saturation effect in which the partly filledguts of Ascomorpha did not permit the total extraction of thecontents of a Ceratium cell.  相似文献   

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