云南青鳉鱼类的分类和分布(鳉形目:青鳉科)

经研究,云南的青鳉鱼类有2种:(1)分布于西双版纳的小青鏘 Oryzias minutillus Smith为中国境内首次记录;(2)另一种是新亚种,定名中华青鳉 Oryzias latipes sinentis subsp.nov.广泛分布于云南及中国其他地区。本新亚种与产自日本的指名亚种日本青鳉 Oryzias latipes latipes Temminck et Schlegel的主要区别在于:本新亚种的第一肋骨连接第二而不是第三脊椎骨上;平均脊椎骨数为29.2±0.6而不是30.3±0.5;胸鳍条多数为9而不是多数为10枚;染色体数目2n=46而不是2n=48。这些差异,明显地表示了由于地理隔离而引起的亚种分化。     

Relationship between Floret Elongation and Pigment Synthesis in the Flowers of Carthamus tinctorius

Floret elongation and levels of precarthamin were investigatedin freshly collected flowers of Carthamus tinctorius. Accumulationof precarthamin was found to be induced at the early stagesof floret elongation. [U-¹⁴C]Acetate and [U-¹⁴C]phenylalaninewere incorporated into precarthamin in the detached floretsfrom the flower bud. The results suggest that precarthamin issynthesized via the acetate-shikimate pathway. Carthamus tinctorius L, floret elongation, pigment synthesis, precarthamin     

Biological activity of phyllosinol, a phytotoxic compound isolated from a culture filtrate of Phyllosticta sp.

1. Phyllosinol is a phytotoxic metabolite of Phyllosticta sp. Thissubstance at 100 µg/ml produced dark grey necrotic lesionson the leaf of red clover. Sensitivities of various plant speciesto phyllosinol differed both quantitatively and qualitatively.
2. Phyllosinol reduced root growth in rice seedlings by 60% at10^–4 M, whereas stimulation of root elongation occurredat a concentration range from 10^–9 to 10^–5 M.
3. Phyllosinolat 2.5x10^–4M promoted adventitious root formationin epicotylsof Azukia cuttings by about 100%. Promotion waspartly reducedby simultaneous application of cysteine.
4. IAA-induced elongationof isolated Avena coleoptile sectionswas inhibited by phyllosinolat a concentration range from 10^–5to 10^–3M.
5. Sulfhydrylcompounds, i.e. cysteine and glutathione relievedinhibitioncaused by phyllosinol in IAA-induced elongation ofAvena coleoptilesections.
6. GA₃-induced elongation of wheat leaf sections wasslightly inhibitedby phyllosinol at 10^–4M.
7. Phyllosinolalso has antibiotic activity. Among the organismstested, Phycomycetesand Gram-negative bacteria appeared mostsusceptible to phyllosinol.

(Received April 21, 1970; )     

Calcium Inhibits Ion-Stimulated Stomatal Opening in Epidermal Strips of Commelina communis L.

Inoue, H. and Katoh, Y. 1987. Calcium inhibitsion-stimulatedstomatal opening in epidermal strips of Commelina communis L.—J.exp. Bot. 38: 142–149. Ca²⁺ suppressed both the ion-stimulated stomatal opening andH⁺ extrusion of pre-illuminated epidermal strips isolated fromCommelina communis L. In the absence of Ca²⁺, the rate of H⁺release was 18 nmol H⁺ cm^–2 h^–1 per epidermal stripunit area in 150 mol m^–3 KCL at pH 7?4. Half-maximum inhibitionof stomatal opening was observed with 220 mmol m^–3 ofCa²⁺. The hexavalent dye, ruthenium red, showed concentration-dependentprevention of the inhibition by Ca²⁺ of the ion-stimulated stomatalopening. The effect of ruthenium red was non-competitive, andthe K₁ for the calcium inhibition was found to be 3?6 mmol m^–3.The calcium inhibition of H⁺ extrusion was also prevented byruthenium red. These results suggest that Ca²⁺ inhibits theactivity of electrogenic H⁺ translocating ATPase of the guardcell plasma membrane and leads to the suppression of stomatalopening. Key words: Calcium, Commelina communis, ruthenium red, stomata     

Reversal of ethylene action on cocklebur seed germination in relation to duration of pre-treatment soaking and temperature

Abstract At 23°C, both C₂H₄ and CO₂ stimulated the germination of freshly imbibed upper cocklebur (Xanthium pennsylvanicum Wallr.) seeds, but C₂H₄, unlike CO₂, changed to an inhibitor of germination under some soaking conditions. However, when seeds were pre-soaked for more than several hours at 23 °C prior to treatment, C₂H₄ strongly inhibited their germination at 33 °C, the degree of inhibition increasing with the duration of pre-soaking. Maximum inhibition occurred at 1–3 cm³ m^?3 C₂H₄ when seeds were pre-soaked for 1 week; further increases of C₂H₄ concentration and pre-soaking period decreased the inhibitory effect. C₂H₄ was synergistic with CO₂ when C₂H₄ promoted germination, whereas it was antagonistic when inhibitory. Such a transition of the C₂H₄ action occurred at ca. 27 °C. Also 1-andnocyclopropane-1-carboxylic acid, a C₂H₄ precursor, inhibited the germination of pre-soaked seeds at 33 °C, although it promoted the germination at 23 °C. When pre-soaked seeds were prepared for germination by chilling at 8 °C for 3 d, the inhibitory effect of C₂H₄ on the subsequent germination was manifested even at 23 °C. The reversal of the C₂H₄ action from promotion to inhibition in cocklebur seed germination is discussed in relation to the engagement of two respiratory pathways in the imbibed seeds.     

Prothoracicotropic Hormone Bioassay: Pupal-Adult Bombyx Assay

Blockage of adult development by brain removal and its resumption by application of the prothoracicotropic hormone (PTTH) were studied using pupae of a racial hybrid J-122 × C-115 of Bombyx mori . A log-linear dose-response relationship was obrained after injection of a PTTH solution. The Bombyx -unit of PTTH has been defined from this dose-response curve.     

Studies on the change of the respiratory system in roots in relation to the growth of plants V. Effect of root pruning terminal oxidase activity in roots of cereal crops

This experiment studies the comparative activities of terminaloxidases (Fe-containing oxidases, Cu-containing oxidases andCN-resistant oxidases) in roots of rice and wheat seedlingsand the effect of root pruning on these terminal oxidases inthe roots of those crops. Data indicate that (i) excepting achange in the activity of Cu-containing oxidases no appreciabledifference in respiration or in Fe-containing and CN-resistantoxidases was noticed in the two types of seedling roots and(ii) root pruning did not produce any noticeable change in terminaloxidase activities in roots of wheat seedlings. A drastic changein terminal oxidase activities in roots of rice seedlings wasobserved, suggesting that a close relationship exists betweenCN-resistant oxidase and transplanting time. (Received November 21, 1968; )     

The Hill reaction and oxygen uptake in isolated pine chloroplasts

1. The Hill reaction and oxygen uptake in chloroplasts preparedfrom pine leaves were studied. Pine chloroplasts active forthe Hill reaction were isolated from mature leaves in the presenceof 25% PEG in the isolation buffer. Time courses of the Hillreaction in chloroplasts isolated from leaves at different seasonsdiffered. In chloroplasts isolated in the autumn, Hill activitydecreased rapidly with illumination time. This rapid decreaseof Hill activity was inferred to result from concomitant productionof some inhibitory substance(s) during the Hill reaction.
2. Theprotective effect of PEG on inactivation by aging of pinechloroplastswas found. In the presence of PEG, chloroplastswere stabilizedand Hill activity was maintained even afterstorage for 26 hr;whereas, in the absence of PEG inactivationby aging proceededrapidly and oxygen uptake occurred after20 hr.
3. Chloroplastsisolated without PEG had no ability of the Hillreaction; but,inversely showed pronounced oxygen uptake. Oxygenuptake wasalso observed in aged or DCMU-inhibited chloroplasts.The presenceof benzoquinone strongly suppressed oxygen uptake.

¹ Present address: Laboratory of Biology and Chemistry, Universityof Naval Architecture of Nagasaki, Nagasaki, Japan. (Received January 27, 1971; )     

Electron flow from hydrogen peroxide in photosystem II-catalyzed oxidation-reduction reactions of spinach chloroplast fragments

Oxidation-reduction reactions of photosystem II were investigatedin spinach chloroplast fragments. Chloroplast fragments treatedwith 8-hydroxyquinoline sulfate showed only a low activity forthe 2,6-dichlorophenolindophenol (DPIP) Hill reaction, as wasobserved in chloroplast fragments treated with a high-concentrationof Tris buffer. Hydrogen peroxide could donate electrons tophotoreaction center II in chloroplast fragments treated with8-hydroxyquinoline, high-concentration Tris, or ethylene glycol,but water could not serve as an electron donor in these preparations.Electrons from hydrogen peroxide were transferred to DPIP, ferricyanide,and p-benzoquinone viaphotosystem II. (Received May 12, 1971; )     

Reactions of photosystems I and II in spinach chloroplast fragments treated with ethylene glycol

Photochemical reactions of chloroplast fragments isolated fromspinach leaves were measured in the presence of ethylene glycolor were measured after washing with an ethylene glycol-containingmedium. 2,6-Dichlorophenolindophenol (DPIP) photoreduction,oxygen evolution and oxygen uptake (a photosystem I reaction)were investigated in ethylene glycol-treated chloroplast fragments.By washing with ethylene glycol, oxygen evolution was stronglyinhibited, but oxygen uptake was not much affected by ethyleneglycol washing. Chloroplast fragments in 50% ethylene glycolmaintained a high rate of DPIP photoreduction (85% of the controlactivity in an ethylene glycol-less medium). In 67% ethyleneglycol, DPIP photoreduction mediated by photosystem II was eliminatedand only a small rapid reduction mediated by photosystem I wasobserved. Chloroplast fragments inhibited by ethylene glycolphotoreduced DPIP in the presence of p-aminophenol added asan artificial electron donor to photosystem II. The restoredactivity of DPIP photoreduction was inhibited by 3-(3',4'- dichlorophenyl)-1,1-dimethylurea. (Received September 8, 1970; )