A pollen factor linking inter- and intraspecific pollen rejection in tomato

Self-incompatibility (SI)--intraspecific pollen recognition systems that allow plants to avoid inbreeding--in the Solanaceae (the nightshade family) is controlled by a polymorphic S locus where "self" pollen is rejected on pistils with matching S alleles. In contrast, unilateral interspecific incompatibility (UI) prevents hybridization between related species, most commonly when the pollen donor is self-compatible (SC) and the recipient is SI. We observed that in Solanum, a pollen-expressed Cullin1 gene with high similarity to Petunia SI factors interacts genetically with a gene at or near the S locus to control UI. Cultivated tomato and related red- or orange-fruited species (all SC) exhibit the same loss-of-function mutation in this gene, whereas the green-fruited species (mostly SI) contain a functional allele; hence, similar biochemical mechanisms underlie the rejection of both "self" and interspecific pollen.     

Recognition and rejection of self in plant reproduction

Plant self-incompatibility (SI) systems are unique among self/nonself recognition systems in being based on the recognition of self rather than nonself. SI in crucifer species is controlled by highly polymorphic and co-evolving genes linked in a complex. Self recognition is based on allele-specific interactions between stigma receptors and pollen ligands that result in the arrest of pollen tube development. Commonalities and differences between SI and other self/nonself discrimination systems are discussed.     

不结球白菜波里马胞质雄性不育系花药发育的细胞形态学研究

以不结球白菜波里马胞质雄性不育系及相应保持系为试材，从显微和亚显微结构两个层次对花药发育进行对比研究。结果表明：不结球白菜Ｐｏｌ ｃｍｓ花药发育受阻于孢原细胞分化期，没有孢原细胞分化，不形成药室。不育系经低温作用后，能产生微量花粉，部分花分能形成隐原细胞，并且能经过造孢细胞，花粉母细胞，四分体，单胞花粉，二胞花粉等阶段而发育成成熟花粉。     

Cloning One CIPK Gene from a Thermo-Sensitive Genic Self-Incompatible Line in Maize Expressing Under Different Temperatures

A calcineurin B-like protein-interacting protein kinases (CIPK) gene was cloned (EU 424058) from a thermo-sensitive genic self-incompatibility (TSGI) line, HE97, in maize, which was selected for suppression subtractive hybridization (SSH) library of the self-incompatible and self-compatible silks of the TSGI line under different temperatures. The full-length cDNA of the candidate CIPK-like gene consisted of 1 918 nucleotides and contained a 1 332-bp open reading frame in maize. Real-time PCR indicated that the candidate CIPK-like gene was highly expressed in the self-incompatible pollen of the TGSI line, and promoted elevated levels of calcium (Ca2+). High Ca2+ concentrations in the pollen strongly inhibit pollen tube formation in silk of the same plant, thus inducing self-incompatibility (SI) under high temperature. These results implied that the CIPKs-like gene would play an important role in the regulation of HE97 characteristics under different temperatures, perhaps acting as a secondary messenger in the expression of SI in the TGSI line in maize.     

植物自交不亲和性的分子生物学进展

自交不亲和性是植物特异性地识别并拒绝白花或亲缘关系很近的花粉的一种遗传机制,该特异性受S基因座控制。S-RNase介导的配子体型自交不亲和性在被子植物中分布最广泛,在茄科、蔷薇科和玄参科植物上研究比较深入。研究表明,雌雄双方的特异性决定因子分别是S基因座中具有多态性的核酸酶和含有F-box结构域蛋白基因,但其他修饰基因也参与其中。本文概括了该类自交不亲和性的研究现状,并根据最新研究进展就其工作模型作进一步探讨,同时简要提出今后的研究方向。     

小麦单细胞培养的研究——再生植株后代花粉母细胞染色体行为与花粉粒育性

在单细胞培养再生植株后代农艺性状和产量性状研究基础上 ,进一步对再生植株后代的花粉母细胞染色体行为和花粉粒育性进行研究。结果表明 ,花粉母细胞染色体行为发生异常 ,出现落后染色体、环形染色体、染色体桥、断片和粘连以及花粉母细胞仅发生核裂、三极纺锤体、多分体等 ,其中多以落后染色体花粉母细胞出现的频率为最高 ,早期世代为 8.0 3 %～ 51.11% ,随着繁殖世代的增加 ,这种异常的比率逐渐降低 ,到高世代 ( SCC6代 )仅为 0 .50 %～ 9.80 %。花粉粒育性分析结果表明 ,尽管早期世代花粉母细胞发生异常的比率较大 ,但各株系的可育花粉粒比例都在 60 %以上 ,并且均表现为正常结实 ,未发现不育现象。随着世代增加 ,育性也在不断改善 ,高世代绝大多数株系可育花粉粒的比例都在 98%以上。再生植株花粉粒的育性与花粉母细胞染色体变化密切有关     

植物花粉扫描电镜技术研究与观察

采用不同扫描电镜样品制备技术制备植物花粉,并用扫描电镜观察比较,发现样品制备方法对植物花粉的微细结构影响很大.其中采用普通样品制备技术制样的花粉出现3种情况:壁薄、含水量大的杨树、苦竹的花粉外观形态和超微结构变化严重;壁稍厚、含水量较小的萱草花粉的外观形态基本保持良好,但超微结构收缩变形;壁较厚、含水量少的鹅掌楸花粉的外观形态和超微结构均保持良好状态.结果表明:不同种类植物花粉的生物性能差别较大,样品制备方案应根据花粉的自身特性制定;对于壁薄、含水量大的花粉样品,在样品制备过程中必须进行固定并消除液体表面张力的影响,才能保持好花粉的外观形态和超微结构特征.     

大果黄花梨自交亲和性变异机制研究

梨品种大果黄花由黄花芽变而来.田间授粉试验表明,黄花梨自花授粉结实率仅为1.5%,属于梨自交不亲和性品种;而大果黄花自花授粉的结实率高达60.0%,属于自交亲和性品种;相互授粉时,黄花×大果黄花组合的坐果率达70.0%,为杂交亲和,但反交时坐果率为1.0%,表现为杂交不亲和.荧光显微镜观察这些组合授粉后花柱内花粉管生长情况,也得到相同的结果.这些结果表明,两品种雌蕊的自交不亲和性性状正常.进一步鉴定出了黄花和大果黄花是基于S-RNase基因的S-基因型,发现两者均含有S1-RNase和S2-RNase基因;而且两品种的这1对雌蕊S-RNase基因均特异性地在花柱中表达,表达量没有明显差异,表明大果黄花和黄花的雌蕊S-RNase基因并无差异.由此推断:大果黄花的自交亲和性突变,是由于花粉自交不亲和性功能丧失,从而表现出自花授粉能够结实.     

Study on the mating compatibility of part pear varieties and wild types of Pyrus ussuriensis

To understand the mating compatibility of Pyrus ussuriensis Maxim., we studied the fertility of pollen and conducted a hand-pollination trial in the field on some pear varieties and wild types. The results showed that about 53% of varieties among 32 tested genotypes were male sterile. Not only did the pollen vitalities in normal varieties show distinct differences, but pollen vitalities from flower forcing in a glasshouse were found to be lower than those from natural flowering in the field, which had no apparent effect on fruit setting of tested varieties. Most of the tested genotypes such as Nanguoli, Pingxiangli, and Hanxiangli showed selfincompatibility (SI). Honghuagaili could bear fruit after hand pollination, but there were abnormal seeds in its fruits. So we suggested it was a recessive SI that happened during embryo development. Longxiangli has the capacity of self-compatibility (SC) to some extent, its fruit setting rate of inflorescence could reach 23.3%. Manual self-pollination during bud flowering could improve the fruit setting rate of part tested genotypes with SI, but had no effect on the fruit setting rate 3 days after flowering. Mating between female parents with the variety selected from F1 generation showed that the majority of their combinations were compatible. There was one-way SC when Nanguoli was crossed with Hanhongli, while no fruits could be found after Hanhongli was crossed with Nanguoli. It may be related to the S-genotype or haplotype of Nanguoli. In addition, mating between the varieties derived from bud mutation with the female parent appeared incompatible. We concluded that P. ussuriensis Maxim. is similar to other grown pear systems with the characteristics of SI, the fruit setting rate of self pollination in some varieties and wild types can be improved by artificial self-pollination during bud flowering, and fruit cannot be developed through pollination between the varieties from bud mutation and the female parent. __________ Translated from Journal of Fruit Science, 2007, 24(4): 427–432 [译自:果树学报]     

大豆光敏雄性不育株88-428BY-827小孢子母细胞的细胞学观察

 以长光照条件下的大豆光敏雄性不育88-428BY的雄性可育株为对照,对其短光照条件下的雄性不育株进行了小孢子母细胞减数分裂的观察。结果表明,88-428BY-827雄性不育株花粉败育在发育各个时期都发生。88-428BY-827雄性不育株小孢子母细胞减数分裂的染色体的行为出现了多种类型的异常现象:联会异常、单价体、三价体、染色体落后、染色体粘连、染色体桥、染色体不均等分离等;单核小孢子阶段小孢子饱满、细胞核内染色体明显且超出正常的染色体数目;少数小孢子的萌发孔为4个;成熟的花粉粒大小不等、形状不规则、甚至形     

甘蓝品种自交不亲和性的鉴定与利用潜力

利用常规测定方法鉴定了基因型差异较大的10个甘蓝品种的自交不亲和性(SI),并就其应用潜力进行了分析,结果表明,甘蓝品种SI的表现随基因型生态类型和来源的不同而异,一般地方品种SI较强,平均SI株率达58.9 %,由SI系配置的杂交种SI较弱,平均SI株率为13.1 %;随着品种熟期延长,自交不亲和性愈强,早、中、晚熟品种的SI株率依次为58.9 %、16.0 %和9.3 %。利用地方品种和外引杂交种都可进行SI等位基因系的定向选育。     

百日草雄性不育系的获得及其细胞学观察

 【目的】获得百日草雄性不育系,并探索其花药发育机制,为百日草杂种优势的利用提供一条新途径。【方法】采用自交F2代出现的不育材料连续回交获得的不育系再进行兄妹交、可育株自交,结合与多个自交系测交进行不育类型鉴定,并对其细胞学进行研究。【结果】获得了百日草深红色单隐性雄性不育两用系AH209AB。正常可育的花药,其药壁由4层细胞构成,即表皮、药室内壁、中层和绒毡层;花粉母细胞减数分裂过程中的胞质分裂为同时型;成熟花粉为三细胞型。雄性不育株花瓣退化或丝状,雄蕊退化成丝状,内无花粉,外观呈绒毛状;花药在造孢细胞组织形成后,没有继续分化产生药壁结构、花粉母细胞及其花粉,为完全的结构性雄性不育类型。【结论】该雄性不育系属于无花粉囊型不育系,在F1代种子生产上具有重要的利用价值。     

利用基因工程创造植物雄性不育的策略

利用基因工程创造植物雄性不育系是近年来发展的新技术。根据花粉败育的原理,利用花药细胞绒毡层、绒毡层线粒体、胼胝质壁、细胞减数分裂过程等花粉形成过程中的不同环节,采取外源细胞毒素基因、分子伴侣、反义RNA技术、提早降解胼胝质、扰乱线粒体与细胞核之间的信息交流和细菌影响花粉小孢子发育等策略,使花粉不能正常形成,从而产生不育花粉,达到产生雄性不育的目的。并提出了基因工程创造植物雄性不育系可能存在的问题及其应用前景。     

CMLs参与调控植物花粉授粉竞争的作用

目的在显花植物生殖过程中花粉萌发和花粉管生长起着至关重要的作用,这一过程受许多因素的影响,其中钙调素类似蛋白（calmodulin-like proteins,CMLs）通过直接或间接的作用机制调控花粉萌发及花粉管生长。然而,迄今人们对CMLs的功能研究尚少。本文旨在初步了解CMLs蛋白在花粉竞争优势中的作用,为深入探究CMLs蛋白在植物花粉竞争优势中的分子机制奠定理论基础。方法本文主要通过对参与调控花粉萌发以及花粉管生长过程的CMLs蛋白的结构、表达水平、细胞定位及其作用机理的归纳,结合不同植物中出现的花粉竞争现象,综合分析并总结国内外相关研究结果。结果CMLs蛋白约有4个保守的EF手性结构域,当CMLs蛋白结合Ca2+时,其构象发生变化,增强与下游受体蛋白的结合能力,并启动Ca2+依赖的级联信号放大效应,引起花粉管中Ca2+的浓度变化,影响从萌发孔到花粉管顶端Ca2+浓度梯度的形成,从而调控花粉管的正常生长。CMLs蛋白的表达还可以影响Mg2+、NO等离子的浓度变化,影响Ca2+与EF手性结构域的结合及花粉管生长的导向。不同CMLs蛋白具有不同生理功能,其中参与花粉萌发及花粉管生长的CMLs蛋白主要在植物花器官中表达;部分显花植物在受精过程中,不同倍性花粉之间可能由于基因组大小或者营养物质含量的差异,导致萌发率及生长速率的不同。结论CMLs蛋白可能通过在不同倍性花粉中的差异表达,影响花粉在体内萌发的进程,使其在某一时期表现出竞争优势。      

运用致病毒素筛选抗烟草黑胫病细胞突变体I抗毒素愈伤组织的有效筛选

以６０Ｃｏ－γ射线照射烟草优质感病品种的花药作为诱变手段,用烟草黑胫病疫霉菌粗毒素为筛选剂,对烟草花粉植株叶片的愈伤组织,进行抗病突变体细胞的筛选．试验表明：毒素对烟草愈伤组织的存活和增殖有明显的抑制作用,抑制程度随毒素浓度提高而加强,同一浓度对不同品种也存在着差异．综合毒素浓度对烟草愈伤组织抑制、增殖程度及筛选的有效性,初步认为：筛选红大和Ｋ３２６抗黑胫病突变体细胞的最适粗毒素浓度分别为３０％和４５％．所筛选出的抗病突变体细胞,其细胞水平的抗性与再生植株的抗病性鉴定相吻合．     

珍汕97A和HN5s育性恢复突变的观察

通过^60Co-r辐照与NaN3复合处理及外加成熟胚培养，对得到的珍汕97A和HN5s育性恢复突变体突变率进行了比较，且对育性恢复突变体自交后代不育株的花粉败育类型、光敏不育株的不育特征进行了分析。结果表明不育系经过诱变处理可以发生：1．不育株向可育株的转变；2．不育株的败育类型由典败向无花粉型、圆败及染败的转变；3．光敏不育株可转变为温敏不育株。由此提出光敏核不育系育性漂移主要是不育基因发生育性恢复突变，又在自交、杂交过程中累积的结果。     

Male Sterile Lines of Zinnia elegans and Their Cytological Observations

In order to find out a new pathway for utilizing heterosis of Zinnia elegans and accelerate breeding process, the mechanism of anther development of a male sterile line was explored. Backcross, sibmating, selling of fertile plants and testcross with inbred lines were analyzed and identified in the field, and cytology was observed. Recessive nucleus male sterile line AH209AB capable of being a maintainer was obtained by successive backcrosses with male sterile plants and fertile F1 plants as male parents. Cytological and anatomical studies indicated that： （1） The wall of normal anther was constituted of four layers of cells such as epidermis, powder chamber wall, middle level and tapetum cells. The process in meiosis of pollen mother cell in Zinnia elegans was normal and cytoplasm divided simultanously. Mature pollen grain was tricellular type. （2） The petal of male sterile plant degraded as a thread-like structure, the stamens were villiform in appearance and no pollens were formed. The result showed that the anther of male sterile plant no longer proceed to differentiate spore mother cell and the pollen sac after the formation of the tissue of sporogenous cells, there was no evident boundary between tapetum cell, middle lamella and inner wall of PMC, tapetal cells did not develop from the very beginning. So the abortion type was completely structural male sterility. The male sterile line belongs to non-sporange male sterile type and is of great use in F1 seeds production.     

大麻花粉母细胞减数分裂染色体行为观察

对大麻减数分裂进行了观察,结果表明:大麻减数分裂进程有一定的规律,与植株形态、花蕾大小、花萼形态和花药色泽有密切关系;供试材料减数分裂染色体行为表现正常,胞质分裂为同时型;大麻减数分裂进程上存在差异,不同植株以及同一植株的不同花蕾花粉母细胞减数分裂时期表现不同步性,甚至同一花药的不同细胞也存在差异。     

植物扩展蛋白基因的研究进展

扩展蛋白基因(expansin genes)是一个相对保守的基因家族,由α、β、γ和δ4个亚家族组成。作为植物细胞壁的重要组成部分,扩展蛋白以酶催化的作用方式,使细胞壁组分间疏松,细胞伸展,细胞的柔韧性增强,以此缓解各种环境因子对细胞的压力。目前研究发现:扩展蛋白参与了植物生长发育过程中的许多环节,如种子萌发、根毛的起始和延长、叶子生长发育、叶柄脱落、花粉管延长、果实成熟等。同时,扩展蛋白还参与了抗旱、抗病、耐高温等诸多抗逆性反应。扩展蛋白基因多属于诱导表达,易受激素、温度、干旱、病原菌、机械损伤等各种内外界环境因素的影响。     

银杏雄株叶片和花粉主要类黄酮成分含量分析

【目的】研究江苏省46个银杏实生雄株(系)叶片和花粉类黄酮化合物主要成分及其含量,为合理开发利用银杏雄株种质资源提供理论依据。【方法】运用HPLC技术分析不同株系叶片和花粉甲醇(乙醇)-盐酸水解溶液中主要黄酮苷元的含量,并采用三因子法计算总黄酮苷含量。【结果】不同银杏雄株叶片和花粉的黄酮含量存在较大差异,通过设定黄酮苷元和总黄酮含量的选择域值,发现扬州有4个品系(扬州03、04、10、20)、泰州有2个品系(泰州08、13)、徐州有2个品系(徐州04、09)符合叶用标准,扬州有10个品系(扬州02、03、04、08、09、10、12、15、18、20)符合花粉用标准。银杏雄株叶片和花粉均含有槲皮素、山奈酚和异鼠李素3种黄酮苷元,但含量不同,叶片中三者差别不大,而花粉中以山萘酚为主,花粉总黄酮平均含量约为叶片的1.42倍。【结论】通过黄酮苷元和总黄酮含量的分析,根据设定的选择指标,可以得到优良的叶用或花粉用单株供生产利用,为银杏雄株资源的综合利用提供了参考。