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1.
介绍了我国辣椒雄性不育研究在细胞学、内源激素、物质代谢等方面取得的新进展,分析了辣椒雄性不育在生产中的应用,并提出了展望. 相似文献
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以甜菜单胚雄不育系和保持系为材料,用光学显微镜对其雌性器官各部发育进行了比较解剖学观察.结果如下:甜菜雌蕊由3—5枚心皮合生而成,外形可分为柱头、花柱和子房三部分。各部解剖学特征:(1)柱头3—5枚离生稍向外生长,柱头正面由大量乳突细胞组成;(2)花柱短小,半开放形,开口较小,其内充满腺毛状结构;(3)半下住子房,心皮合生一室,在外侧愈合交界处,有发达的盘状蜜腺;胚珠1枚基底胎座,曲生形胚珠,双珠被厚珠心.蓼形胚囊,并有盲囊结构产生。研究表明,甜菜雄不育和可育的雌蕊、胚珠、胚囊形态结构相似,均可正常发育,两者均具有受精与结实能力. 相似文献
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种子败育型无核葡萄胚发育及败育的细胞学研究 总被引:1,自引:0,他引:1
以种子败育型葡萄火星无核、康能无核为试材,系统研究其胚发育及败育的细胞学进程,分析胚乳败育与胚败育的关系。结果表明,种子败育型无核葡萄与有核葡萄的胚均能发育到球形胚阶段,但不同品种发育到该阶段的时间不同,火星无核在花后28~37 d处于球形胚阶段,康能无核在花后31~40 d,有核葡萄白香蕉的球形胚阶段是花后28~40 d,随后无核葡萄的胚逐渐败育,而有核葡萄的胚历经心形胚和鱼雷形胚阶段,最后发育成熟。种子败育型葡萄胚乳败育均早于胚败育,可能是胚败育的直接原因。火星无核、康能无核胚挽救适宜取材时期分别在花后34 d和花后40 d。 相似文献
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De Vico G Sfacteria A Maiolino P Mazzullo G 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2002,31(1):16-18
Background — Nuclear morphometry may provide useful diagnostic and prognostic information for neoplasms in animals. Most available data have been obtained from histologic sections. Nuclear morphometry of cytologic smears may provide important pre-operative information.
Objectives — The goal of this study was to compare nuclear morphometric parameters in cytologic smears and histologic sections from spontaneous canine tumors.
Methods — Mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear form factor (FF; nuclear perimeter2 /4π nuclear area) and their respective SDs were assessed by image analysis of both hematoxylin and eosin-stained histologic sections and May-Grünwald-Giemsa-stained cytologic smears from the same case in 20 spontaneous canine tumors of different histogenesis. The above parameters were selected as being the best morphometric tools for measuring variation in shape and size in cells after neoplastic transformation. Data were compared by ANOVA with P<.01 considered significant.
Results — There was a significant difference between histologic and cytologic specimens for MNA, MNP, and their SDs. Only the differences between FF and the SD of FF were not statistically significant.
Conclusions — Only nuclear morphometric data related to nuclear shape and nuclear shape variability are comparable between histologic and cytologic specimens. Nuclear area and perimeter may be affected by the different fixation and smear preparation techniques used in histology and cytology. 相似文献
Objectives — The goal of this study was to compare nuclear morphometric parameters in cytologic smears and histologic sections from spontaneous canine tumors.
Methods — Mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear form factor (FF; nuclear perimeter
Results — There was a significant difference between histologic and cytologic specimens for MNA, MNP, and their SDs. Only the differences between FF and the SD of FF were not statistically significant.
Conclusions — Only nuclear morphometric data related to nuclear shape and nuclear shape variability are comparable between histologic and cytologic specimens. Nuclear area and perimeter may be affected by the different fixation and smear preparation techniques used in histology and cytology. 相似文献
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Two wide hybrids, Diplotaxis erucoides (2n = 14) × Brassica rapa (2n = 20) and B. maurorum (2n = 20) × B. rapa, were developed using the sequential ovary–ovule culture. Reciprocal crosses failed, possibly as a consequence of strong
unilateral incompatibility. The F
1 hybrids in each combination were completely male sterile and morphologically intermediate to the respective parents. DNA
marker polymorphism and chromosome counts confirmed their hybrid nature. High frequency of bivalents in the F
1 and the presence of trivalents/quadrivalents in the derived amphiploids suggested genomic duplications and homoeology of the
parental genomes. Up to three homoeologous pairs between the D. erucoides (DeDe) and B. rapa (AA) genomes, and one between B. maurorum (BmBm) and B. rapa genomes were observed. Successful synthesis of the F
1 hybrids and amphiploids of B. rapa with D. erucoides and B. maurorum, and allosyndetic chromosome pairing are expected to permit introgressions of desirable loci into the cultivated Brassica
germplasm, especially for resistance to Alternaria
brassicae and Albugo candida. 相似文献
9.
黄瓜抗霜霉病异源易位系CT201的筛选与鉴定 总被引:8,自引:0,他引:8
将栽培黄瓜‘北京截头’ (Cucumis sativus L. , 2n = 14) 与Cucum is属双二倍体新种C. hytivus (2n = 38) 回交, 随后自交。通过霜霉病田间接种试验筛选, 从中发现抗霜霉病单株HH12825。将HH12825与C. hytivus的原始亲本‘北京截头’和野生种C. hystrix进行农艺性状对比观察, 发现此单株在叶面积、节长、果长×果径等方面介于栽培黄瓜和野生种之间, 在侧枝数、果刺颜色等方面偏向野生种。观察其花粉母细胞减数分裂过程, 发现其PMC中期Ⅰ多价体频率(56% ±8% ) 和后期Ⅰ二价体分离滞后率(72% ±5% ) 都较高, 具有染色体易位的细胞学特征。进一步利用RAPD分子标记分析, 结果在40个随机引物中找到了两个引物( E219: ACGGCGTATG和A I220: CCTGTTCCCT) 能够在HH12825中重复地扩增出原始亲本野生种C. hystrix特异DNA片断, 从分子水平上证明了其为黄瓜异源易位系, 并把此易位系命名为CT201。 相似文献
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