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991.
van der Meer  John P. 《Hydrobiologia》1990,204(1):389-395
Sporelings of the monoecious red alga Gelidium vagum were placed into 4500 individual cultures after treatment with the chemical mutagen nitrosoguanidine and raised to sexual maturity to search for reproductive mutants. Isolates undergoing normal self-fertilization were discarded, leaving approximately 250 self-sterile plants and mutants with abnormal reproduction or reproductive structures. Self-sterile mutants were tested further in crosses to a fertile green marker stock. From the results, many mutants appeared to be either male-sterile, female-sterile or unable to form carposporophytes. Although sufficient data on the inheritance pattern of the self-sterile mutants are available for only a few of the isolates, some apparently stable sterility mutations with simple Mendelian transmission were identified. Preliminary testing of one of the male-sterile mutations confirmed that it effectively eliminated self-fertilization and facilitated the formation of hybrid plants in crosses.  相似文献   
992.
Moderate stimuli in mitochondria improve wideranging stress adaptability in animals, but whether mitochondria play similar roles in plants is largely unknown. Here, we report the enhanced stress adaptability of S-type cytoplasmic male sterility(CMS-S) maize and its association with mild expression of sterilizing gene ORF355. A CMS-S maize line exhibited superior growth potential and higher yield than those of the near-isogenic N-type line in saline fields. Moderate expression of ORF355 induced t...  相似文献   
993.
哒嗪类化合物9403诱导小麦雄性不育的初步研究   总被引:12,自引:2,他引:10  
9403是国内新合成的一种哒嗪类化合物,经初步研究证明,9403具有诱导小麦雄性不育的作用。试验以GENESIS化学杂交剂为对照,对9403诱导小麦雄性不育的作用进行了研究。结果表明;9403对试验的两个品种西农6419与BAU95在其花药发育的药隔期,用剂量0.75kg/hm^2进行一次叶面喷施,诱导雄性不育率可达到96%以上,人工饱和授粉证明9403对雌蕊的育性没有影响,平均人工饱和授粉结实率为88.6%,与GENESIS相比,9403的杀雄效果较不彻底且具有一定的药害。  相似文献   
994.
红莲型细胞质雄性不育水稻线粒体DNA的RFLP分析   总被引:19,自引:3,他引:16  
李小明  郑用琏  张方东  朱英国 《遗传》2000,22(4):201-204
应用RFLP技术,研究了红莲型不育系、保持系、杂种一代及野败型、马协型不育系的线粒体基因组。结果表明,红莲型不育系与保持系线粒体基因组之间在多个基因区域存在明显差异,为红莲型细胞质雄性不育分子机理研究提供了线索;红莲型不育系与野败型不育系的线粒体基因组之间存在显著差异,马协型不育系与野败型不育系的线粒体基因组之间存在一定差异,在分子水平揭示了不育胞质的多样性。 Abstract:Restriction fragment length polymorphism (RFLP) was used to analyze rice mitochondrial genome.The results indicated obvious differences between mt genome of rice cytoplasmic male sterile line and its maintain line of Honglian type,which further clued CMS mechanism research.Mitochondrial genome difference between sterile line of Honglian type and Wild Abortive type was obvious,some difference between sterile Maxie and Wild Abortive was also detected,it offered molecular evidence for cytoplasmic heterogeneity.  相似文献   
995.
996.
Cytoplasmic male sterility in the olive (Olea europaea L.)   总被引:1,自引:0,他引:1  
The olive tree is usually hermaphrodite but self-incompatible. In the Western Mediterranean some cultivars are totally male-sterile. Three different male-sterile phenotypes have been recognised. To infer the genetic basis of male sterility we studied its inheritance and cytoplasmic diversity in wild (oleaster) and cultivated Mediterranean olive. In the cross Olivière×Arbequina, the male-sterile trait was maternally inherited and affected all progenies. We also checked that both chloroplast and mitochondrial DNAs are maternally inherited. RFLP studies on chloroplast and mitochondrial DNAs revealed several cytotypes: two chlorotypes and four mitotypes in cultivars and oleaster (wild or feral Mediterranean olive). Furthermore, a total linkage desequilibrium between the CCK chlorotype and the MCK mitotype in cultivars and oleaster from different regions supports the fact that paternal leakage of organelles was not observed. The male sterility (ms 2) displayed by Olivière, plus six other cultivars and three oleaster was strictly associated with the CCK chlorotype and the MCK mitotype. These facts suggest that Olivière carries cytoplasmic male sterility. Male-fertile and male-sterile oleasters carrying this cytotype showed the presence of restorer alleles. This CMS might be due to a distant cross between olive taxa. The two other male-sterile phenotypes displayed by Lucques (ms 1) and Tanche (ms 3) were associated with the ME1 mitotype but we have not demonstrated CMS. Received: 26 July 1999 / Accepted: 27 August 1999  相似文献   
997.
水稻不育系的不育机理至今尚未搞清。本工作对红莲型不育系小孢子发育过程中花药蛋白质的变化进行了分析,为从分子水平阐明其不育机理奠定基础。分别在不育系(A)、保持系(B)、杂种一代(F1)和恢复系(R)的花粉母细胞单核、二核及三核四分体时期取花药,匀浆、反复离心制备上清液、定量后,做不连续Bis-Acr凝胶电泳、染色,观察其蛋白电泳条带的变化。结果见Fig.1&2和Tab.1:大多数主要的、表达量大的蛋白质在二核期前后(花粉败育时期),没有明显变化,这些蛋白与败育无关。条带X、XI随着小孢子发育过程出现变化,但它们在A、B、F1和R中的表达行为变化一致,也与败育无关。条带Ⅰ、Ⅱ在不育系中不表达,条带Ⅲ为不育系所特有,条带Ⅳ在单核期以后出现,条带Ⅶ在二核期受到抑制,它们均可能与育性有关。A、F1中均有条带Ⅴ表达,说明该编码基因是由不育系遗传到F1中的,它与育性无关;而R、F1系中均有条带Ⅵ、Ⅷ表达,该编码基因可能是由恢复系遗传到F1中的,可能涉及F1的育性恢复。  相似文献   
998.
杨征  朱英力 《遗传学报》1999,26(5):518-523
对水稻配子体细胞质雄性不育系粤泰A,保持系粤泰B,F1代泰优2号和孢子体细胞质雄性不育系珍汕97A,保持系珍汕97B,F1代汕优63及另一种孢子体细胞质雄性不育系马协A,保持系马协B,F1代马协63的黄化苗线粒体离体翻译产物进行SDS-PAGE分析。结果表明:粤泰A的线粒体比粤泰B,泰优2号少合成2条多肽,B与F1的带型相近,A特异合成40.7kD多肽;  相似文献   
999.
Cytoplasmic male-sterile (CMS) chicories have been previously obtained by somatic hybridisation between fertile industrial chicory protoplasts and CMS sunflower protoplasts. In this study, we compared three different CMS chicory cybrids that originated from three different fusion events. The cybrids were backcrossed with different witloof chicories in order to transfer the three male-sterile cytoplasms from an industrial chicory nuclear environment to a witloof chicory nuclear context. Southern hybridisation, using different mitochondrial genes as probes, revealed that the three cybrid mitochondrial genomes were different and that they were stable throughout backcrossing generations regardless of the pollinator. However, pollinators were found to influence floral morphologies – with one being able to restore fertility – showing that nuclear context can affect the sterility of the cybrids. PCR and RFLP analyses revealed that the orf522 sequence, responsiblefor CMS in PET1 sunflower, was present in two out of the three cytoplasms studied, namely 411 and 523, but was absent from the other cytoplasm, 524. We thus concluded that orf522 is not responsible for CMS in the 524 cybrid. Although the orf522 gene is present in the 411 and 523 cytoplasms, it is probably not responsible for the sterile phenotype of these cybrids. Received: 3 June 1998 / Accepted: 30 April 1999  相似文献   
1000.
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