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1.
Different varieties of citrus exhibit a great variation in their susceptibility to infestation by the red scale, Aonidiella aurantii. Among the thirteen varieties investigated, mandarin clemantine, santara and baladi, orange baladi and rough lemon are the most resistant; while lemon baladi, sour orange and grapefruit are the most susceptible. The susceptibility to infestation decreases with the increase of oil glands in the leaves and fruits of citrus. The total amount of nitrogen, phosphorus and carbohydrates in the leaves of different varieties shows no correlation with their susceptibility to infestation.
Résumé Différentes variétés de Citrus montrent de grandes variations dans leur sensibilité aux attaques par Aonidiella aurantii. Parmi les 13 variétés étudiées, les plus résistantes sont: mandarine clémentine, mandarine baladi et rough lemon, tandis que lemon baladi; sour orange et pamplemousse sont les plus sensibles.La sensibilité aux infestations décroît proportionnellement avec l'accroissement du nombre des glandes à huiles essentielles sur les feuilles de citrus. La quantité totale d'azote, de phosphore et d'hydrates de carbone dans les feuilles des différentes variétés ne montre aucune corrélation avec leur sensibilité aux infestations.
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2.
Summary To determine the effect of a taurine-enriched drink Red Bull on performance, 10 endurance-athletes performed three trials. After 60 min. cycling at approximately 70% VO2 max, the subjects pedalled to exhaustion on a cycle ergometer. During each exercise, the subjects received 500 ml of a test-drink after 30 min. submaximal cycling: Red Bull without taurine, without glucuronolacton (U1), Red Bull without taurine, without glucuronolacton, without caffeine (U2) and Red Bull original drink containing taurine, glucuronolacton and caffeine (U3).The heart rate level was significantly lower in U3 (p = 0,0031) 15 min. after application. The plasma catecholamines increased slightly from begin of exercise to 15 min. after application of the drinks in all trials but remained on a significantly lower level in U3 (epinephrine (p = 0,0011) and norepinephrine (p = 0,0003). Endurance time was significantly longer with Red Bull original in U3 (p = 0,015). The results of this study show a positive effect of a taurine-containing drink on hormonal responses which leads to a higher performance.  相似文献   

3.
Summary The aim of this study was to determine whether DNA variations could be detected in regenerated pea plants. Two different genotypes were analyzed by cytogenetic and molecular techniques: the Dolce Provenza cultivar and the 5075 experimental line. Dolce Provenza regenerated plants showed a reduction in DNA content, particularly at the level of unique sequences and ribosomal genes. Moreover, regeneration was associated with an increase in DNA methylation of both internal and external cytosines of the CCG sequence. On the other hand, the DNA content of the 5075 line remained stable after regeneration. DNA reduction was found only in 5075 plants regenerated from callus cultures maintained for long incubation periods (about a year). The DNA variations observed are discussed both in relation to the genotype source and the role of tissue-culture stress.  相似文献   

4.
Axillary shoot induction and plant regeneration were obtained in Plantago ovata. The optimum medium for inducing axillary shoots was Murashige & Skoog (MS) medium [5] supplemented with 4.6 M kinetin and 0.05 M NAA. Rooting of shoots was best on half-strength MS medium containing 5.0 M IBA and 0.05 M kinetin. The regenerated plants were similar to the control plants in karyotypic and phenotypic details.  相似文献   

5.
Somatic embryo formation was induced from cotyledon explants of Styrian pumpkin (Cucurbita pepo L. subsp. pepo var. styriaca Greb.) by using a solid MS medium supplemented with 16.11M NAA and 4.44M BA or 26.85M NAA and 13.32M BA. The callus proliferation was more efficient on medium supplemented with 26.85M NAA and 13.32M BA. In contrast, the embryogenic response was higher on medium with lower concentrations of growth regulators (16.11M NAA and 4.44M BA). The time needed for embryo induction did not depend on medium composition. Embryos in globular stage were transferred to three different maturation media, containing 2.89M GA3 in combination with 0.54M NAA, 11.42M IAA and growth regulator-free medium. The germination rate was the highest when embryos were cultured on medium with 11.42M IAA. Plantlets grown on this medium achieved maturity suitable for transplantation into soil within 9 to 10weeks. The regenerated plants were successfully transferred into field and developed fertile flowers and set fruits. Biochemical analysis showed significant lower total glutathione levels among in vitro grown plantlets compared to seedlings grown in soil. When the plantlets were transferred into soil, they reached a normal size within a month and the glutathione concentration was comparable to seed-derived plants at the same developmental stage. Transmission electron microscopy was used to investigate possible differences in the ultrastructure of cells from callus cultures, and leaf cells of regenerated and seed-derived plants. Differences in the ultrastructure were found within chloroplasts which contained only single thylakoids, large starch grains and small plastoglobuli in callus cells in comparison to leaf cells, which possessed a well developed thylakoid system, small starch grains and large plastoglobuli.  相似文献   

6.
Résumé L'autoradiographie révèle, au niveau du pied, une incorporation massive et sélective de la 3H-Proline dans la glande blanche de Mytilus edulis. Cette étude a permis de suivre le processus qui mène de la synthèse de la sécrétion dans la partie basale des cellules jusqu'a son émission dans le sillon pédieux où elle participe à la formation du filament. La collagénase détruit la presque totalité du marquage, attestant ainsi la nature collagénique du produit sécrété. Les autres glandes pédieuses ainsi que la glande du byssus proprement dite, située à la base du pied, montrent une incorporation très faible, sans commune mesure avec celle de la glande blanche. Ceci démontre de façon définitive que le collagène présent dans le filament prend naissance dans cette glande et justifie la dénomination de glande du collagène. Des contrôles réalisés dans différentes régions (bords du manteau, manteau, branchies) montrent que l'injection du précurseur dans le bord palléal constitue une méthode satisfaisante pour marquer de façon relativement rapide et différentielle le collagène de la glande.
The collagen of the byssus in Mytilus edulis L.II. Autoradiographic study on the incorporation of 3H-Proline
Summary Autoradiographic studies reveal a strong specific incorporation of 3H-Proline in the white gland in the foot of Mytilus edulis. The author could trace the radioactive secretory product from its synthesis in the basal part of the cells down to its outflow into the pedial groove where it takes part in the formation of the filament. Purified collagenase takes out radioactivity from the sections. This observation confirms the collagenous nature of the secretion.The other foot-glands as well as the main byssus gland located at the base of the foot show but a very weak labelling not comparable with that of the white gland. This clearly evidences that the collagen occuring in the filament originates from the latter. The white gland may be properly called: collagen gland.Control sections through different parts of the body (mantle-edge, mantle, gills) confirm that our injection technique of the precursor into the palleal margin is a suitable method for a rather quick and specific labelling of the glandular collagen.
Cette note fait partie d'un travail pour l'obtention d'une thèse de doctorat.  相似文献   

7.
In vitro plant regeneration was achieved inCapsicum praetermissum, C. baccatum andC. annuum cvs. G4, Bhiwapuri Sweet pepper, Cayenne pepper and Hybrid pepper. Shoots were induced from hypocotyl, cotyledon and leaf explants on Murashige and Skoog medium supplemented with 5.7 M indoleacetic acid (IAA)+13.3 M benzyladenine (BA); 22 M BA; and 44 M BA. Analysis of variance revealed that the most significant effect on shoot regeneration was due to the explant and it accounted for 56.3% of total variation observed. The genotype x explant effect on regeneration was minor relative to all other 2- and 3-way interactions because leaf explants consistently regenerated more shoots than hypocotyls or cotyledons in all the genotypes and thereby reduced the variation among the genotypes. Explant x medium interaction revealed that 22 M BA was the best growth regulator supplement in regeneration medium for optimal shoot regeneration from leaf explants. Rooting of regenerated shoots was achieved on 5.7 M IAA-containing medium, and the rooting response was better from shoots induced on medium fortified with 5.7 M IAA plus 13.3 M BA. Complete plantlets with diploid chromosome number (2n=2x=24) were transferred to soil and 60–70% of these plantlets survived and grew well.  相似文献   

8.
Summary Antisera against oLH1, oLH and hFSH were used to localize gonadotropic cells in the pars distalis of Cercopithecus aethiops and Papio hamadryas. Three separate cell types were observed for FSH and LH: 85% of immunohistochemically identified gonadotropic cells reacted to all the various antisera; 10% reacted with the anti-LH antibody only; and 5% with the anti-hFSH antibody only. Comparisons between adjacent serial sections treated with various antisera, other than anti-gonadotropic hormones, demonstrated that the gonadotropic cells of these monkeys did not respond to these antisera.
Résumé Des anticorps anti-LH ovine, anti-LH ovine et anti-FSH humaine ont été utilisés pour localiser les cellules gonadotropes dans la pars distalis de l'hypophyse des Singes Cercopithecus aethiops et Papio hamadryas. Trois catégories cellulaires distinctes, réagissant avec des anticorps anti-hormones gonadotropes, ont été observées. 85% des cellules immunoréactives identifiées en tant que cellules gonadotropes réagissent simultanément avec les différents anticorps mentionnés; 10% des cellules gonadotropes réagissent seulement avec l'anticorps anti-oLH et 5% de ces cellules seulement avec l'anticorps anti-hFSH. La comparaison avec des coupes adjacentes traitées par divers anticorps autres que les anticorps anti-gonadotropines prouve que les cellules gonadotropes de ces Singes ne réagissent jamais simultanément avec l'un ou l'autre de ces anticorps.

Abbreviations used in this Article oLH ovine luteinizing hormone - hFSH human follicle stimulating hormone - ACTH corticotropin - GH growth hormone - LPH lipotropin - TSH thyrotropin  相似文献   

9.
The stable isotope ratios of nitrogen were measured in the mysid,Neomysis intermedia, together with various biogenic materials in a eutrophic lake, Lake Kasumigaura, in Japan throughout a year of 1984/85. The mysid, particulate organic matter (POM, mostly phytoplankton), and zooplankton showed a clear seasonal change in 15N with high values in spring and fall, but the surface bottom mud did not. A year to year variation as well as seasonal change in 15N was found in the mysid. The annual averages of 15N of each material collected in 1984/85 are as follows: surface bottom mud, 6.3 (range: 5.7–6.9); POM, 7.9 (5.8–11.8); large sized mysid, 11.6 (7.7–14.3); zooplankton, 12.5 (10.0–16.4); prawn, 13.2 (9.9–15.4); goby, 15.1 (13.8–16.7). The degree of15N enrichment by the mysid was determined as 3.2 by the laboratory rearing experiments. The apparent parallel relationship between the POM and the mysid in the temporal patterns of 15N with about 3 difference suggests the POM (mostly phytoplankton) as a possible food source ofN. intermedia in this lake through the year.  相似文献   

10.
Callus induction from petiole explants has been achieved in Alocasia micholitziana `Green Velvet'. The highest percentage (71%) of explants inducing callus was obtained on MS medium supplemented with 0.5 M 2,4-D and 0.5 M kinetin in the dark after 4 months of culture. Shoots were regenerated at the highest frequency of 33.3% under light condition when 0.5 M BA was added to MS medium with the average of 7.8±2.3 shoots per callus explant. The callus-derived shoots rooted on hormone free MS medium and within 4 weeks the plantlets were ready for acclimatization. The regenerated plants appeared morphologically similar to mother plants.  相似文献   

11.
Role of trichomes in soybean resistance to cabbage looper, Trichoplusia ni   总被引:1,自引:0,他引:1  
Role of leaf trichome density and length in Glycine max (L.) Merr. resistance to Trichoplusia ni (Hübner) was evaluated at different leaf positions on a relatively resistant soybean, plant introduction (PI) 227687, and a relatively susceptible cultivar, Davis. The uppermost (juvenile) leaf within both PI 227687 and Davis plants, which is densely covered with trichomes, was most resistant to T. ni larval feeding and survival. When these trichomes were shaven off, such leaves became as susceptible to T. ni larval feeding as unshaven TL3 and TL5 leaves (PI 227687) or all other unshaven leaves (Davis). Bioassays for antifeedants in ethyl acetate and hexane extractables from leaves at the different positions on PI 227687 and Davis plants showed that the resistance observed in the uppermost Davis leaf is attributable to trichomes (i.e., a morphological factor); whereas, in the uppermost PI 227687 leaf it involves both morphological (trichomes) and chemical factors, but the trichome parameter is dominant.
Résumé L'influence de la densité et de la longueur des trichomes de Glycine max sur la résistance à Trichoplusia ni a été évaluée suivant la position des feuilles sur une lignée résistante (PI 227687) et sur un cultivar sensible (Davis).Les feuilles apicales (juvéniles) tant de PI 227687 que de Davis, recouvertes de trichomes denses, résistèrent mieux à l'alimentation larvaire et à la survie de T. ni.Quand ces trichomes étaient éliminés, ces feuilles ne résistaient pas plus à l'alimentation des larves de T. ni que les feuilles non rasées TL3 et TL5 de PI 227687 ou toutes les autres feuilles de Davis.Les tests avec des extraits dans l'acétate d'éthyle et l'hexane de feuilles provenant de différentes positions de PI 227687 et Davis, destinés à mettre en évidence des phagodissuadants, ont montré que la résistance observée chez les feuilles apicales de Davis était attribuable aux trichomes (c'est-à-dire à un caractère morphologique), tandis que chez les mêmes feuilles de PI 227687 elle impliquait à la fois des trichomes (morphologie) et des substances chimiques, mais avec une prédominance de l'influence des trichomes.
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12.
Atriplex gmelini plants were regenerated via organogensis from hypocotyl explants. Callus lines were induced from the hypocotyl explants on Linsmaier and Skoog (LS) medium supplemented with 1 M benzyladenine and 5 M -naphthaleneacetic acid in the dark. Shoots were regenerated from the callus lines on LS medium supplemented with 20 M thidiazuron and 0.1 M -naphthaleneacetic acid under a high-intensity light condition (450 mol m–2 s–1). The regenerated shoots were rooted on LS medium without growth regulators to obtain fully developed plants. We succeeded in transforming Atriplex gmelini from callus lines using Agrobacterium tumefaciens.  相似文献   

13.
Two new asterosaponins, (20R)-3-O--D-(2-O-methylxylopyranosyl)-24-propylcholest-4-ene-3,6,8,15,16,29-hexaol (sanguinoside A) and (20R,24S)-3-O--D-(2,3,4-tri-O-methylxylopyranosyl)-5-cholestane-3,4,6,8,15,24-hexaol (sanguinoside B), were isolated from two species of Pacific Far Eastern Starfish Henricia sanguinolenta and H. leviuscula leviuscula, collected in the Sea of Okhotsk. Both glycosides contain aglycones with pentahydroxysteroid nuclei of similar structures, which are substituted at the 3-hydroxy group with differently methylated -D-xylosyl residues. Sanguinoside A has an unusual structure of its aglycone side chain, whereas sanguinoside B has a unique permethylated carbohydrate chain. In addition, laevisculoside G, a known glycoside, was identified in the H. leviuscula starfish. The structures of the isolated glycosides were established by interpreting their spectral data and by comparing their spectral characteristics with those of known compounds.  相似文献   

14.
Summary Isoelectric focusing of extracts from the endosperm of mature grains of hexaploid wheat and related species was used to study the genetic control of Iodine binding factor (IBF). Ten IBF bands were present in Chinese Spring (CS) and analysis of the nullisomictetrasomic and ditelosomic lines of CS showed nine of them to be controlled by genes on the long arms of the homoeologous group 5 chromosomes. Five alleles were detected at Ibf-A1 locus, four at Ibf-B1 and four at Ibf-D1 among a sample of 46 wheat genotypes. Homoeoloci were found on chromosome 5R of Secale cereale, 5E of Agropyron elongatum, 5U of Aegilops umbellulata, 5Agi of Agropyron intermedium, 5S1 and 4S1 of Aegilops sharonensis and 4H of Hordeum vulgare.  相似文献   

15.
Hybridizations ofElymus nutans andE. jacquemontii were carried out with one species ofPseudoroegneria (S genome), and 20Elymus species, each containing either of the SH, SY, SYH, or SYW genomes. Chromosome configurations were analysed at metaphase I of the two target taxa and their interspecific hybrids. It is concluded that (i)E. nutans is an allohexaploid containing the SYH genomes, andE. jacquemontii is an allotetraploid having the SY genomes; (ii) the genomic affinity is associated with the geographic distance between the species studied; (iii) minor genomic structural rearrangements have occurred within the hexaploid taxon ofE. nutans.  相似文献   

16.
Oocysts of Isospora ernsti n. sp. and Isospora blagburni n. sp. are described from the black-capped bulbul Pycnonotus xanthopygos from Lincoln Park Zoo, Chicago, Illinois. The bird came from southwestern Africa seven years earlier. I. ernsti oocysts are ellipsoidal to bluntly ovoid, 28–38 × 23–31m (mean 34 × 28 m) and have a single-layered oocyst wall. Micropyle, oocyst residuum and polar granules are absent. Sporocysts are elongate ovoid, 24–30 × 11–16 m (mean 27×13 m). Stieda and substiedal bodies and sporocyst residuum are present. I. blagburni oocysts are spherical to subspherical. 21–28 × 19–26 m (mean 25 × 23 m) and have a single oocyst wall. Sporocysts are ovoid and 17–23 × 10–13 m (mean 20 × 12 m). Stieda and substiedal bodies and sporocyst residuum are present.  相似文献   

17.
Eryngium foetidum L. plants were regenerated from mature leaf and petiole explants through direct organogenesis without intervening callus phase. From leaf explants, adventitious multiple shoots raised on Murashige and Skoog (MS) medium supplemented with 4.43 M benzylaminopurine (BAP) and 0.57 M indole-3-acetic acid (IAA), whereas in petiole explants shoot regeneration occurred at 8.86 M BAP and 0.57 M IAAA. 80% of the leaf explants and 44% of petiole explants produced shoots after four weeks of culture. The regenerated plants were rooted on MS medium supplemented with 2.46 M indole-3-butyric acid and 2.88 M gibberellic acid. The plants were successfully established in the soil and showed 70.9% survival in the field.  相似文献   

18.
D. C. Morgan  H. Smith 《Planta》1978,142(2):187-193
Chenopodium album seedlings were grown in light environments in which supplementary far-red light was mixed with white fluorescent light during various parts of the photoperiod. Both the logarithmic rate constant of stem extension and the leaf dry weight: stem dry weight ratio were linearly related to estimated phytochrome photoequilibrium () in each treatment regime. These data are taken to be indicative of a functional link between phytochrome and development in the green plant. A layer of chlorophyllous tissue only affected the linearity between calculated and the logarithmic stem extension rate at high chlorophyll concentrations, whilst even low concentrations-equivalent to the levels found in stem tissue-caused a significant shift in measured . End-of-day supplementary far-red (FR) light induced between 0–35 per cent of the response elicited by all-day supplementary FR, whilst daytime supplementary FR (with a white fluorescent light end-of-day treatment) induced approximately 90 per cent. The ecological significance of this difference is discussed with respect to shade detection.Paper 7 in the series The function of phytochrome in the natural environment [for paper 6 see McLaren, J.S., Smith, H., Plant, Cell and Environment 1, 61–67, 1978]  相似文献   

19.
Summary Transmission of paternal chloroplasts was observed in Nicotiana, considered to inherit organelles in a strictly maternal way. Plants carrying streptomycin resistant plastids were used as pollen donors. Cell lines with paternal plastids in the offspring were selected as green (resistant) sectors on calli induced from the seedlings on streptomycin-containing media. The presence of paternal plastids in the regenerated plants was confirmed by restriction analysis. In the Nicotiana plumbaginifolia xN. plumbaginifolia Np(SR1)3 and the N. plumbaginifolia Np(gos)29 xN. tabacum SR1 crosses 2.5% and 0.07% of the offspring were found to contain paternal (tabacum) plastids, respectively. These plants, however, carried maternal mitochondria exclusively. This sexual cybridization method offers a simple way to transfer chloroplasts solely, a goal not accessible by protoplast fusion.  相似文献   

20.
J. B. Fiol 《Mycopathologia》1973,51(2-3):207-215
Résumé Pichia vini etPichia vini var.melibiosi sont comparées en tenant compte des systèmes enzymatiques intracellulaires et non plus seulement des caractères d'assimilation du cellobiose et du mélibiose. La présence de système enzymatique susceptible d'hydrolyser les glucosides chezP. vini var.melibiosi et les galactosides chezP. vini sont des arguments valables pour synonymiser les 2 variétés.
Pichia vini andPichia vini var.melibiosi are compared in respect to their intracellular enzymatic systems concerning cellobiose and melibiose. Both species possess intracellular glucosidase and galactosidase with the same characteristics. It seems that the separation between the 2 varieties is not valuable after our results.


Étude particulière de l' galactosidase et de la-glucosidase, conséquences taxonomiques.  相似文献   

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