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991.
Young spinach (Spinacia oleracea L., cv. Subito) and wheat (Triticum aestivum, cv. Tonic) plants were hydroponically grown in eight different nutrient solutions containing 137Cs. Ca, Mg, K and NH4 concentrations were varied whilst anion concentrations were equal in all solutions. The large differences in potassium content between spinach and wheat were not reflected in similar differences in 137Cs content at any nutritive treatment.Both crops were also grown in a potted podzolic soil contaminated with radiocaesium. This experiment was conducted in a phytotron at two climatic conditions (summer and winter) which differed in day length and light intensity. Wheat plants had higher 137Cs levels than spinach at both conditions. The 137Cs levels furthermore decreased during development. The 137Cs plant/soil solution concentration ratio was lower at the summer than at the winter conditions. 相似文献
992.
Bert Overduin Saskia A. Hogenhout Erik A. van der Biezen Michel A. Haring H. John J. Nijkamp Jacques Hille 《Molecular & general genetics : MGG》1993,240(1):43-48
The fungal disease resistance locus Alternaria stem canker (Asc) in tomato has been suggested to encode the enzyme aspartate carbamoyltransferase (AC Tase). To test this hypothesis a segment of the tomato ACTase gene was amplified by the polymerase chain reaction (PCR) using degenerate primers. The PCR product obtained was subsequently used to isolate an ACTase cDNA clone. Restriction fragment length polymorphism (RFLP) linkage analysis showed that the ACTase gene and the Asc locus do not cosegregate. RFLP mapping positioned the ACTase gene on chromosome 11, while the Asc locus is located on chromosome 3. These results exclude the possibility that the ACTase protein is encoded by the Asc locus. 相似文献
993.
Photoinhibition of isolated mesophyll cells from cold-hardened and non-hardened winter rye 总被引:1,自引:1,他引:0
Cold-hardened rye leaves have been shown to be more resistant to low temperature photoinhibition than non-hardened rye leaves. Isolated mesophyll cells from winter rye (Secale cereale L. cv. Musketeer) were exposed to photoinhibitory light conditions to estimate the importance of leaf morphology and leaf optical properties in the resistance of cold-hardened rye leaves to photoinhibition. Cold-hardened rye cells showed more resistance to photoinhibition than non-hardened rye cells when monitored with chlorophyll a variable to maximal fluorescence ratio (Fv/Fm). Thus, leaf morphology does not contribute to the resistance of cold-hardened rye leaves to low temperature photoinhibition. However, cold-hardened and non-hardened rye cells showed a similar extent of photoinhibition when photsynthetic CO2 fixation rates were measured. They also showed the same capacity to recover from photoinhibition. During both photoinhibition and recovery, Fv/Fm and light limited CO2 fixation rates showed different kinetics. We propose that inactivation and subsequent reactivation during recovery of some light activated Calvin cycle enzymes explain the greater extent of photoinhibition of light limited CO2 fixation and its faster recovery compared to Fv/Fm kinetics during photoinhibition. 相似文献
994.
995.
埃斯基红豆草下胚轴愈伤组织原生质体的培养与植株再生 总被引:4,自引:0,他引:4
埃斯基红豆幼苗的下胚轴切段在附加2,4-D0.5mg/L,KT1mg/L的MS中形成胚性愈伤组织。来自11-13个月龄、继代6-15天的愈伤组织的原生质体,在改良的V-KM液体培养基中可持续分裂形成细胞团,培养10天时的分裂率和克隆率分别为65.88%和53.38%周后就可将将原生质体形成的小愈伤组织转于培养基上。原生质体在改良的B5液体培养基也可以分裂形成小愈伤组织,但分裂率低于V-KM。来自原 相似文献
996.
997.
钙对不同成熟期番茄果实的PG活性及其合成的影响 总被引:11,自引:0,他引:11
本文研究了钙处理不同成熟期番茄果实对果壁组织中钙含量与转化、多聚半乳糖醛酸酶(PG)活性与 PG 合成的影响。结果表明,钙处理绿熟期的番茄果实可使总钙和可溶性钙含量明显增加,并较多转化为结合钙;后期处理,进入和转化的钙都减少。同样,钙处理愈早,对果实 PG 活性的抑制愈强,绿熟期处理可完全抑制 PG 活性。凝胶电泳结合钌红染色,证明绿熟期果实无 PG,PG 是在果实成熟过程中新合成的。钙处理愈早,对 PG 合成的抑制愈强,绿熟期钙处理可完全抑制 PG 合成。 相似文献
998.
Frequent spontaneous deletions of Ri T-DNA in Agrobacterium rhizogenes transformed potato roots and regenerated plants 总被引:1,自引:0,他引:1
Charlotte H. Hänisch ten Cate Annelies E. H. M. Loonen Marie Paule Ottaviani Liesbeth Ennik Gerben van Eldik Willem J. Stiekema 《Plant molecular biology》1990,14(5):735-741
The presence of T-DNA was examined by Southern blot analysis in 16 regenerated shoot lines derived from 6 Agrobacterium rhizogenes-transformed root clones of Solanum tuberosum L. cv. Bintje.TR-DNA, present in regenerated shoot lines from 3 out of 6 root clones was correlated with the presence of opines. One root clone produced opines up to 2.5 years of subculture. However, plant regeneration from and prolonged subculturing of this root clone resulted in loss of opine synthesis, caused by deletion of TR-DNA.TL-DNA inserted at 1 to 5 independent loci was found in 14 of the 16 shoot lines. Surprisingly, 1 to 2 additional insertions next to similar insertions of TL-DNA were found in shoot lines from the same root clone (named sister shoot lines) in 2 out of 4 root clones. Nevertheless, this did not result in gross phenotypic variation between sister shoot lines. Another root clone regenerated 1 shoot line with an Ri phenotype, containing 1 insertion of TL-DNA, and 2 shoot lines with a normal Bintje phenotype without TL-DNA. The 5th root clone showed no difference between sister shoot lines and the 6th root clone produced only 1 shoot line.We conclude that during prolonged root culture and during shoot regeneration from root clones deletion of TL- and TR-DNA insertions can occur. The significance of the frequency of deletion of T-DNA of the Ri plasmid is discussed. 相似文献
999.
本文对黄花菜三个品种进行了细胞学研究。三个品种的染色体数目均为22,核型有所不同,核型公式分别为:线黄花2n=2x=22=12m+10sm;马连黄花2n=2x=22=10m+10sm+2st(SAT);小黄花2n=2x=22=6m+14sm+2st。核型均属2B型。线黄花与马连黄花的核型接近。细胞学研究说明,根据植物形态分类划分的黄花菜三个品种是确切的。 相似文献
1000.
玫瑰新品种—蜀玫精油化学成分的研究 总被引:1,自引:0,他引:1
用毛细管气相色谱-质谱-计算机数据处理联用技术,毛细管气相色谱保留指数它性法和标准品叠加法分析了玫瑰嫁接新品种——蜀玫(Rosa chinensis Jacq.x R.multiflora+R.rugosa Thunb.)精油的化学成分,并与接穗-素玫(Rosa rugosa cv.’Plena’)的精油成分进行了比较. 玫瑰精油是一种名贵的香料,在天然香料中占有极其重要的地位.为提高其质量国内外的育种专家对其品种的选育进行了大量的工作.金德伟等人以小叶多花藤玫(Rosa chinensis Jacq XR.mutiflora Thunb.)作为砧木,以素玫(Rosa rugosa Thunb.)作为接穗.培育出一玫瑰新品种——蜀玫(Rosa chinensis Jacq.xR.multiflora+R.rugosa Thunb.),大大地提高了玫瑰花的产量。研究其精油成分的变化以确定其品质是必不可少的.本文就其成分进行了研究。 相似文献