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81.
Anneli Ritala Kristian Aspegren Ulrika Kurtén Marjatta Salmenkallio-Marttila Leena Mannonen Riitta Hannus Veli Kauppinen Teemu H. Teeri Tor-Magnus Enari 《Plant molecular biology》1994,24(2):317-325
Transgenic, fertile barley (Hordeum vulgare L.) from the Finnish elite cultivar Kymppi was obtained by particle bombardment of immature embryos. Immature embryos were bombarded to the embryonic axis side and grown to plants without selection. Neomycin phosphotransferase II (NPTII) activity was screened in small plantlets. One out of a total of 227 plants expressed the transferred nptII gene. This plant has until now produced 98 fertile spikes (T0), and four of the 90 T0 spikes analyzed to date contained the nptII gene. These shoots were further analyzed and they expressed the transferred gene. From green grains, embryos were isolated and grown to plantlets (T1). The four transgenic shoots of Toivo (the T0 plant) produced 25 plantlets as T1 progeny. Altogether fifteen of these T1 plants carried the transferred nptII gene as detected with the PCR technique, fourteen of which expressed the nptII gene. The integration and inheritance of the transferred nptII gene was confirmed by Southern blot hybridization. Although present as several copies, the transferred gene was inherited as a single Mendelian locus into the T2 progeny. 相似文献
82.
Changes in in vivo fluorescence quenching in rye and barley as a function of reduced PSII light harvesting antenna size 总被引:1,自引:0,他引:1
Stefan Falk Marianna Krol Denis P. Maxwell David A. Rezansoff Gordon R. Gray Norman P. A. Huner 《Physiologia plantarum》1994,91(4):551-558
The relationship between the size of the light harvesting antenna to photosystem II (LHCII) and quenching of non-photochemical and dark level fluorescence was studied in wild-type rye (Secale cereale L. cv. Musketeer) and barley (Hordeum vulgare L. cv. Gunilla) as well as in the barley chlorophyll b-less chlorina F2 mutant (H. vulgare L. cv. Dornaria, chlorina-F2). Exposure for 10 min to an irradiance of 500 μmol m?2 s?1 resulted in a strong (0.71–0.73) non-photochemical (qs) quenching of the fluorescence yield in wild-type (WT) material, while the barley chlorina F2-mutant was quenched to 75% of this level. Relaxation of qs in darkness revealed a fast initial decay, related to relaxation of the high-energy-state dependent (qE) part of qs. Etiolated seedlings of rye and barley exposed to intermittent light (IML) for 36 cycles of 2 min light and 118 min darkness had suppressed Chl b and LHCII-production in both WT rye and barley, while the barley chlorina F2-mutant became totally devoid of all LHCII-polypeptides. It was found that the levels of qs and qs were similar in control grown barley chlorina F2 and IML-grown WT rye and barley, but qs was reduced by 30 to 35% and qs by 50 to 65%, respectively, as compared to control-grown. WT plants. No significant qs could be detected in IML-grown barley chlorina F2. It is clear, from these changes in in vivo fluorescence quenching in rye and barley that a significant level of qs is detectable even in the absence of LHCII. Only when the proximal antennae are totally absent, does qE completely disappear. We conclude that the presence of LHCII is not an absolute requirement for qE-quenching and suggest that distal as well as proximal antenna may contribute to qE in vivo. 相似文献
83.
84.
The interfering effects of copper, zinc, and cobalt on the uptake of mugineic acid-ferric complex were studied in barley ( Hordeum vulgare , cv. Minorimugi) grown in nutrient solution. Short-term uptake experiments of 3 h were performed utilizing both ionic and mugineic acid-complex forms of each metal at two different concentrations. Copper was most effective in decreasing iron uptake when added in an ionic form at either concentration. The inhibition order at higher concentrations followed Cu(II) > Zn(II) ≥ Co(II), Co(III), which is consistent with the stability constants of these metal complexes with mugineic acid. The displacement of iron from its mugineic acid complex by these metals is suggested as a probable explanation for the decreased iron uptake. The inhibitory effect of metal complexes with mugineic acid on iron uptake was only found in cases with higher concentrations of Cu(II) and Zn(II) complexes. Deformation of the specific iron transport system in the plasma membrane due to their adsorption may be responsible for this effect. 相似文献
85.
Immature zygotic embryos from spring barley cv. Dissa were used to induce somatic embryogenenesis. Up to 158 germinated somatic embryos could be recovered per plated zygotic embryo. Critical factors for obtaining a high yield of regenerants were the size of the explant, the level of 2,4-D used for callus induction and the careful division of callus at each subculture. Use of microsections of immature embryos as explants revealed a pronounced gradient of callus formation and embryogenic response across the scutellum. Sections from the scutellar tissue at the coleoptilar end of the embryo gave the most callus and were highly embryogenic. The regeneration response of sectioned explants was comparable to that recovered from intact embryos of similar size. 相似文献
86.
Field investigations of ammonia exchange between barley plants and the atmosphere. I. Concentration profiles and flux densities of ammonia 总被引:5,自引:2,他引:3
J. K. SCHJOERRING A. KYLLINGSBAEK J. V. MORTENSEN S. BYSKOV-NIELSEN 《Plant, cell & environment》1993,16(2):161-167
The exchange of ammonia between the atmosphere and the canopy of spring barley crops growing at three levels of nitrogen application (medium N, high N and excessive N) was studied over two consecutive growing seasons by use of micrometeorological techniques. In most cases, ammonia was emitted from the canopy to the atmosphere. The emission started around 2 weeks before anthesis, and peaked about or shortly after anthesis. The volatilization of ammonia only took place in the daytime. During the night-time, atmospheric ammonia was frequently aborbed by the canopy. Occasionally, plants in the medium and high N treatments also absorbed ammonia from the atmosphere during the daytime. Daytime absorption of ammonia never occurred in the excessive N canopy. The loss of ammonia from the canopy amounted in both years to 0.5–1.5 kg NH3-N ha?1 and increased with the N status of the canopy. In agreement with the small losses of ammonia, the content of 15N-labelled nitrogen in the plants did not decline during the grain-filling period. The experimental years were characterized by very favourable conditions for grain dry matter formation, and for re-utilization of nitrogen mobilized from leaves and stems. Consequently, a very high part of the nitrogen in the mature plants was located in grain dry matter (80–84% in 1989; 74–80% in 1990). The efficient re-utilization of nitrogen may have reduced the volatilization of ammonia. 相似文献
87.
BARE-1, a copia-like retroelement in barley (Hordeum vulgare L.) 总被引:5,自引:0,他引:5
88.
89.
在细叶黄芪叶肉原生质体发育早期,细胞器的变化较大。离体培养4h后,线粒体的嵴和基质物质开始增加。培养3—5天后,线粒体的数量增加5倍以上,此时可见大部分线粒体围绕细胞核分布。在培养24h后,高尔基体开始发育,它们主要分布在细胞质周边区域。多糖细胞化学染色表明,高尔基体内沉积着大量嗜银物质。培养1天后,粗面内质网开始发育。培养3天时,部分叶绿体边缘出现一些空隙结构。随着叶绿体内膜结构的消失,淀粉粒增大,叶绿体逐渐转变为造粉质体。 相似文献
90.
菜心(BrassicacampestrisL.ssp.chinensisvar.utilis)叶子高速捣碎后,滤液经酸碱处理,硫酸铵分步沉淀,凝胶柱层析等步骤分离纯化溶菌酶,酶比活力达3414.6U/mg,纯化倍数为197.4。菜心溶菌酶在较宽的温度或pH值范围均有活性,最适温度为60℃,最适pH值为5.8,底物Km值为87μg/mL。该酶对热和酸碱的稳定性较高,巯基和酪氨酸残基不是该酶活性中心的必需基团。 相似文献