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101.
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103.
苹果链格孢菌侵染对感病苹果品种叶细胞超微结构的影响 总被引:1,自引:0,他引:1
将Alternaria mali分生孢子接种在苹果元帅品种叶片的下表皮,保湿培养3~24h,观察细胞超微结构,接种后3h,表皮及叶肉细胞的质膜发生内陷,出现囊泡,暗染色颗粒及管状结构,叶绿体膜结构解体,电子致密物质沉积,基粒排列混乱松散,外膜破裂等。接种后24h,叶片表面出现病斑,细胞质浓缩,细胞壁出现颗粒物,细胞变形,病健组织交界处,叶绿体基浓缩,出现脂质球,同时还观察到,距离病斑2mm处,许多叶肉细胞中出现密度均匀、形状不规则的物质,小叶脉木质部中出现电子致密物质沉积。 相似文献
104.
To develop a male sterile line of eggplant (Solanum melongena L.) utilizing the cytoplasm of S. virginianum, an interspecific F1 hybrid between S. virginianum and S. melongena ‘Senryo Nigou’ was continuously backcrossed to S. melongena ‘Uttara’ using ‘Uttara’ as a recurrent pollen parent and four backcross generations, BC1, BC2, BC3 and BC4 were produced. All the plants in backcross generations were anther indehiscent although the F1 hybrid, S. virginianum and S. melongena were dehiscent. Pollen stainability with acetic carmine and in vitro germination ability of pollen in all the backcross progenies were quite lower than those of the parental species. Fruit set percentage, number of seeds per fruit and seed germination rate were high in all the backcross progenies. The present results indicate that anther indehiscent type of functional male sterile line of eggplant could be developed by utilizing the cytoplasm of S. virginianum. PCR-RFLP analysis of chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) were performed to identify the organelle inheritance. The F1 hybrid and all the backcross progenies displayed maternal inheritance of mtDNA. The cpDNA of the examined single BC1 plant exhibited the recombinant cpDNA pattern of the parental F1 hybrid and ‘Uttara’, indicating occurrence of the biparental inheritance of cpDNA. As all the BC2, BC3 and BC4 progenies showed the same recombinant cpDNA patterns of the BC1 plant, the recombinant cpDNA might be stable and harmonize with the nuclear genome of S. melongena. The present male sterile line can contribute to expand the male sterility source of eggplant. 相似文献
105.
Mukkamala Lakshmi Padmanabhan Senthilkumar Madasamy Parani Mundaya Narayanan Jithesh Ajay Kumar Parida 《Euphytica》2000,116(3):243-250
Twenty-eight species belonging to five genera of the sub tribe Cajaninae; viz., Cajanus(15 species), Rhynchosia (10 species), Dunbaria, Flemingia and Paracalyx were analysed for variations in four chloroplast generegions, rbcL, trnS-psbC, 16S and trnL-UAA. The four chloroplast gene regions were amplified with specific primers and subsequently digested with 15 restriction
enzymes. Rhynchosia did not show any inter-specific differences in the four gene regions for any of the enzymes used. In Cajanus, the inter-specific PCR-RFLP profile of the four gene regions for all the enzymes were similar except for the Pst I digests of trnS-psbC gene region. At inter-generic level, rbcL gene region did not show polymorphism with any of the enzymes used; while in trnS-psbC gene region polymorphism was observed only with Pst I and Hae III digestions. Inter-generic PCR-RFLP of 16S did not reveal any variation. The trnL-UAA gene region had restriction site only forEcoR I in which Cajanus and Rhynchosia showed similar profiles while Dunbaria showed a different profile. The trnL-UAA gene region in Paracalyx and Flemingia did not have restriction site for this enzyme. Despite the analyses of four gene regions using 15 restriction enzymes, differentiation
at genus level could not be obtained. These observations indicated limited divergence of the chloroplast genome among the
four genera of the sub-tribe Cajaninae suggesting close relationships of the taxa.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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[目的]探讨盐逆境下光合器官的光合潜力,为提高全株光合能力提供理论依据。[方法]以耐盐性不同的水稻品种Pokkali(耐盐)、Peta(盐敏感)幼苗为材料,研究叶绿体光能转化对盐胁迫的响应。[结果]结果表明:随着NaCl胁迫浓度和时间的增加,2个水稻品种净光合速率、叶绿体放氧活性、ATP含量下降;100 mmol/L NaCl胁迫下,叶绿体ATP酶活性先上升后基本不变,叶绿体光合磷酸化活力先上升后下降;200 mmol/L NaCl作用下,叶绿体ATP酶、叶绿体光合磷酸化活性一直下降;且耐盐品种Pokkali下降的程度明显小于盐敏感品种Peta。[结论]盐胁迫下耐盐品种叶绿体光能转化能力强于盐敏感品种。 相似文献
108.
以多叶苜蓿、普通三叶型苜蓿(Medicago sativa)为研究对象,利用LI-6400便携式光合作用测定仪和透射电镜考察2类苜蓿叶片光合参数及叶绿体超微结构,比较分析苜蓿不同复叶类型的光合特性差异,探讨多叶型苜蓿的光合特性和在育种实践上的应用提供理论依据。结果表明:多叶型苜蓿的净光合速率(P_n)、气孔导度(G_s)、胞间CO_2浓度(C_i)、蒸腾速率(T_r)平均高于三叶型苜蓿,而气孔限制值(L_s)和叶片瞬时水分利用效率(WUE)平均低于三叶型苜蓿.多叶苜蓿的P_n平均在25.79μmol·m~(-2)·s~(-1)左有,光合效率显著大于普通三叶型苜蓿。不同复叶叶型的苜蓿净光合效率的排列顺序是5叶型4叶型3叶型6叶型7叶型8叶型9叶型。5叶型复叶叶肉中每细胞的叶绿体数目最多,叶绿体中基粒多,基质浓厚,基粒片层堆积致密,嗜锇体数目较少、体积小,每叶绿体中的淀粉粒数目多而饱满。以5为基数叶片数目再增加时,叶绿体个数减少,基粒数日减少、基粒片层结构排列松散,嗜锇体的数目增加、体积变大,淀粉粒数目减小,体积变小。多叶苜蓿的光合效率显著大于普通三叶型苜蓿,多叶型复叶小叶数为5时,净光合效率最大。 相似文献
109.
Two primers, designed according to the Arabidoposis thaliana Toc33 sequence, were used to amplify the full coding region of the Toc33 cDNAs in leaves of a chlorophyll-reduced (Cr) mutant Cr3529 and its wild type 3529, Brassica napus,by RT-PCR technique. The RT-PCR results showed that the fragment homologous to Toc33 was expressed in Cr3529 as well as 3529 seedlings. PCR fragments were inserted into the pMD18-T vector and transferred into E. coli, then two cDNA clones, BnToc33-c and BnToc33, were obtained. Sequence analysis showed that the two sequences were 894 bp and the nucleotide and the deduced amino acid sequences were highly homologous to those of A. thaliana. There were three diverged nucleotides between the Cr3529 and the 3529 Toc33 cDNAs, i.e., GGT/AGT, TTG/TTT, AGG/AGT, all of which belonged to missense mutation. The amino acid replacement ((Leu/Phe) caused by TTG/TTT mutation located in the membrane anchor domain may result in chlorophyll-reduced character in Cr3529. 相似文献
110.