桔梗雄性不育种质JXB-1的发现与鉴定

2006年在龙井市当地采集的3年生野生桔梗种源圃中发现雄性不育种质JXB-1个体,本研究对其生殖发育进行了进一步的实验验证。结果表明：JXB-1个体花的外观与正常的花比较无明显差异,但花药皱瘪;花药开裂,但无花粉粒散出,强行挤出来的花粉粒多数呈不规则型且无活力;套袋自交座果率为零,与30份不同桔梗种源杂交座果率为100%;经花药发育及小孢子发生过程观察,初步认为JXB-1花粉的败育主要发生在小孢子发育时期,JXB-1的绒毡层细胞过早解体,因而小孢子发育中途停止是败育的主要原因。用组织培养方法进行无性繁殖的JXB-1后代全部表现为雄性不育。初步研究结果表明JXB-1确属雄性不育,与其他种源有高度亲和力,可作为优良的育种材料。     

雄性不育与可育楸树花发育的细胞学比较研究

楸树（Catalpa bungei C.A.Meyer.）属紫葳科(Bignoniaceae)梓树属(Catalpa),落叶乔木,是我国特有的珍贵优质用材树种。本文用石蜡切片法对可育株和雄性不育株楸树的大、小孢子发生及雌、雄配子体发育过程进行了详细地比较观察。结果表明：可育株和不育株楸树雌蕊的发育基本相同,胚珠倒生,薄珠心,单珠被,胚囊发育为蓼型。可育株雄蕊花药四室,药隔薄壁组织发达;异型绒粘层,由药壁绒粘层和药隔绒粘层组成;花药壁表皮细胞在小孢子母细胞减数分裂前后开始径向伸长加厚,直到花药开裂并不降解,这可能与花药开裂有关;成熟花粉为四合花粉。雄性不育株花药的早期发育到次生造胞细胞时期与可育雄蕊的相同,小孢子母细胞减数分裂前绒毡层发育不充分;四分体时期,绒毡层细胞高度液泡化,细胞质稀薄,已提前降解,小孢子四分体因绒毡层结构和功能异常而不能正常发育,因此楸树雄性不育为结构型雄性不育。     

不结球白菜雄性不育系及其保持系花药发育的细胞学观察

以不结球白菜（Brassica campestris ssp．chinensis Makino）雄性不育系及其保持系为试验材料,选择不同发育阶段的花蕾,取其花药,制成石蜡切片和超薄切片,经染色后在电子显微镜下观察。结果表明,不结球白菜雄性不育系与保持系的花药发育有明显的不同：不育系花药发育受阻于花粉母细胞分化期,形成1～3个药室,并形成正常的四分体小孢子,此时细胞组织逐步解体,形成空腔花药;最后向内皱缩;保持系花粉母细胞能形成正常的四分体,进而形成小孢子,最终形成充满正常花粉粒的花药。     

辣椒雄性不育材料小孢子发生的细胞形态学观察

用石蜡切片技术,在光学显微镜下观察了辣椒雄性不育材料1A及其保持系1B的小孢子发育过程和各时期的形态特征.结果表明,雄性不育材料1A的小孢子败育发生在四分体至单核花粉粒时期,此时绒毡层细胞异常肥大,四分体受到挤压后破裂并降解,无法形成正常的单核花粉粒.扫描电镜观察结果表明,保持系1B的花粉粒结构完整,表面有3个明显的萌发沟;而雄性不育材料1A的成熟花粉粒形状不规则,空瘪,有部分花粉粒解体,败育比较彻底,说明该雄性不育材料在辣椒育种工作中有较高的利用价值.     

小盐芥小孢子发生和雄配子体发育研究

在显微水平上研究了小盐芥的小孢子发生及雄配子体发育过程,以及不同阶段与花蕾外部形态的相关性.本实验报道的小孢子发生及雄配子体发育的研究结果表明:雄蕊为四强雄蕊,每个花药具4个花粉囊.小孢子母细胞减数分裂属同时型,小孢子在四分体中的排列方式属四面体型.成熟花粉粒属3-细胞型,有3个萌发沟.花粉囊壁发育属双子叶型,由4层细胞构成——表皮、药室内壁、中层和绒毡层.绒毡层为腺质绒毡层.植株花蕾肉眼可见时,雄性孢原细胞开始分化.花蕾露白即蕾长1.1~1.7 mm时,形成成熟的雄配子体,即3-细胞花粉粒.     

粉背薯蓣雄花的形态发生

通过田间观察与石蜡切片法,对粉背薯蓣雄花的发生发育进行了形态与解剖学观察。结果表明:粉背薯蓣雄花为功能上的单性花,花芽分化时雄蕊原基正常启动,随后,3枚雄蕊正常发育,3枚雄蕊退化。成熟雄蕊药隔分叉、变宽呈加厚短叉状,退化雄蕊呈花丝状,顶端分叉或膨大成瘤状。初步分析了花部构件的演变与功能的关系。对粉背薯蓣小孢子发生及雄配子体发育过程的观察表明,花药具4个花粉囊,花药壁发育为单子叶型,由表皮、药室内壁、中层1层和绒毡层组成,绒毡层为腺质型。小孢子母细胞减数分裂后胞质分裂为同时型,四分体为四面体型排列,偶有左右对称型排列,成熟的花粉粒为二细胞型。     

二倍体芒小孢子发生及雄配子体发育研究

该实验通过采集天然二倍体芒不同发育时期的幼穗,进行卡宝品红染色压片和石蜡切片制作,观察芒的花药发育过程,为芒的生殖生物学及其系统发育研究奠定理论基础。结果表明:(1)天然二倍体芒雄蕊3枚,雄蕊花药四室,花药壁由4层细胞组成,从外向内依次是表皮、药室内壁、中层、绒毡层,花药壁发育属于基本型;花药成熟时,中层和绒毡层降解消失,或者仅存痕迹,只剩表皮和纤维层细胞,但此时可观察到部分绒毡层降解延迟现象。(2)花粉母细胞减数分裂为连续型,成熟花粉粒为3-细胞型;花粉母细胞减数分裂后期Ⅱ出现染色体分裂不同步现象。(3)雄配子体发育过程中,同一花粉囊的花粉粒发育不同步;雌、雄配子体发育也不同步,且雄蕊先成熟。     

甜椒胞质雄性不育雄配子发育的解剖学和超微结构研究

运用石蜡切片和电子显微镜超薄切片方法观察了甜椒(Capsicum annuum L．)细胞质雄性不育系8A和保持系8B雄配子发育过程。结果表明：不育系和保持系都能正常进行减数分裂,绒毡层细胞无明显差异,形成了正常的四分孢子。在四分体单核居中期后,不育系的绒毡层细胞异常膨大并伸进药室,挤压花粉粒,同时绒毡层细胞提前降解,不育系单核晚期花粉粒开始崩出内含物。致使不育系的雄配子在双核花粉粒形成之前就完全裂解,不能发育成正常的花粉粒。此外,超薄切片还观察到不育系花粉粒在单核早期绒毡层细胞线粒体空泡化,这种变化表明雄性不育的遗传缺陷包括在花药发育早期发生的线粒体结构变化。     

辣椒胞质雄性不育系和保持系内源激素含量的比较

以2个辣椒品系(199807、199803)的胞质雄性不育系和相应保持系为实验材料,采用酶联免疫吸附法(ELISA)测定IAA、(Z ZR)、GA3和ABA等内源激素含量,用气相色谱分析仪测定乙烯(ETH)释放量,对辣椒胞质雄性不育系和相应保持系内源激素含量变化规律进行研究.实验结果表明:在四分小孢子之前,花药中的IAA含量不育系显著高于保持系,在四分小孢子时期花药和花蕾中的IAA含量出现转折,到花粉粒成熟期的花蕾和花药以及开花期叶片中的IAA含量均是不育系显著低于保持系;小孢子各发育时期花药以及花期叶片中GA3含量均是不育系高于保持系,但花粉粒成熟期化蕾中GA3含量为不育系低于保持系;小孢子不同发育时期的花药以及花期叶片中ABA含量始终足不育系显著高于保持系,而花粉粒成熟期花蕾中ABA含量不育系与保持系没有显著差异;花粉粒成熟期的花蕾和花期叶片中ETH释放量表现为不育系显著高于保持系.同时,花粉粒成熟期的花蕾、花药和叶片中IAA/ABA、(Z ZR)/ABA、GA3/ABA、IAA/GA3、(Z ZR)/GA3等5个激素的比值均有不育系低于保持系的趋势.本实验结果说明辣椒的育性表现与花器和叶片等组织中内源激素的含量变化有关,花药和花期叶片中IAA亏缺、GA3和ABA增加以及化蕾和叶片中ETH过度产生,都有可能导致辣椒雄性不育.     

黄连木大小孢子发生和雌雄配子体发育研究

采用石蜡切片法和整体染色透明法对黄连木大、小孢子发生及雌、雄配子体发育过程进行了研究.结果表明:黄连木雄花有4～5枚雄蕊,每花药具4个花粉囊,花药壁由表皮、药室内壁、中层(2～3层)和绒毡层组成,绒毡层为腺质型.小孢子母细胞减数分裂后胞质分裂为同时型,四分体为正四面体型和左右对称型,四分体时期可观察到少量的二分体.成熟的花粉粒为2-细胞型,球形或近球形,具2～4个萌发孔.雌花单子房,1室,1胚珠,单或双珠被,厚珠心,胚珠倒生,胚囊发育为蓼型.     

宁夏枸杞雄性不育材料小孢子发生的细胞形态学观察

采用常规显微制片法,在光学显微镜下观察了宁夏枸杞雄性不育材料'YX-1'与可育材料'宁杞1号'的小孢子发生过程和各时期的形态特征.结果表明:不育材料'YX-1'小孢子发育受阻于四分体时期,无法形成正常的单核花粉粒,败育的特征是四分体胼胝质壁不能适时降解,四分孢子在胼胝质壁内液泡化、核质收缩降解,绒毡层细胞异常肥大增生,推迟解体.压片结果表明,不育材料'YX-1'四分孢子形状不规则、空瘪、解体,败育比较彻底.     

丹参雄性不育系Sh-B的鉴定与花粉发育过程的解剖学研究

在显微水平上对新发现的丹参雄性不育系Sh-B花药发育过程进行了解剖学观察,并对其花粉活力和结实率进行了鉴定。结果显示:根据花器官及花药的形态、大小以及花丝的长度,可以将Sh-B不育株分为3个不育类型,即Sh-B1、Sh-B2和Sh-B3。这3种不育类型均属于雄性不育,其花丝不到正常可育株的1/2,花药干瘪而瘦小,内无花粉粒或花粉无活力;其根、茎、叶以及种子形态结构与正常可育植株基本相似。产生雄性不育的主要原因有:花粉囊药室内壁纤维层加厚,影响花药壁开裂;小孢子母细胞周围不产生胼胝质或产生的胼胝质很少;绒毡层细胞延迟解体;花粉粒畸形。在其花药发育的小孢子母细胞时期、四分体形成前期、单核期、双核期均可能产生雄性不育的小孢子或花粉粒。     

甘蓝胞质雄性不育系及其保持系花药和叶片生化特性分析

对甘蓝胞质雄性不育系CMS158及其保持系花药激素、游离氨基酸和叶片叶绿素含量进行了比较研究。结果表明,不育系花药KT和IAA含量极显著低于保持系,GA含量不育系和保持系没有显著差异。游离氨基酸总量不育系花药极显著高于保持系,脯氨酸和胱氨酸含量不育系花药极显著低于保持系,赖氨酸含量两系无明显差异,苏氨酸在两系中均未检出,其余氨基酸含量均是不育系花药高于保持系;不育系花药中丝氨酸含量最高,保持系花药中脯氨酸含量最高,两系中天冬氨酸和脯氨酸含量的差异最大。叶片叶绿素含量不育系和保持系无显著差异。     

Production of transgenic male sterile tobacco plants with the cDNA encoding a ribosome inactivating protein in Dianthus sinensis L.

The ribosome inactivating protein (RIP) gene from D. sinensis was used as a cytotoxin gene to induce male sterility in tobacco plants. The TA29 promoter, obtained by PCR amplification from tobacco, was fused to the RIP cDNA, and the chimaeric molecule was then introduced into tobacco plants by Agrobacterium-mediated transformation. Out of twenty-one independent transformants, twenty transgenic tobacco plants exhibited male sterility. Southern blot analysis revealed that four of the transgenic plants contained a single copy of the RIP gene, while the rest of the transgenic tobacco plants had two to four copies of the gene. The transgenic male sterile plants set seeds normally when pollinated with pollens from untransformed control plants, indicating that the RIP gene does not affect the pistil development. Furthermore, the seed yield of the transgenic plant was similar to that of the untransformed, self-pollinated control plant. A light microscopic observation of anther cross sections clearly showed that the tapetal tissue of the anther was selectively and completely destroyed causing male sterility. This study suggests that the RIP gene can be used as a cytotoxin gene for induction of male sterility in the plant.     

枸杞多糖的抗炎镇痛作用研究

为研究枸杞多糖的抗炎镇痛效应及其潜在分子机制,采用小鼠热板实验、小鼠福尔马林炎症疼痛模型和原代培养的背根神经节神经元细胞对疼痛指标和炎症相关分子进行了检测。实验结果显示枸杞多糖能显著缓解后足注射福尔马林引起的动物II相痛表现(P <0. 05),减少动物两后足重量差值(P <0. 001)和血液(P <0. 001)、脊髓(P <0. 05)组织中白细胞介素6的含量,而对小鼠热板潜伏期无明显影响;枸杞多糖降低原代培养的DRG细胞膜上TRPV1介导的钙信号(P <0. 05)。结果证明枸杞多糖具有良好的抗炎镇痛作用,其镇痛机制可能与降低炎症因子白细胞介素6表达及其引起的TRPV1活性增加有关。     

Down‐regulation of OsSPX1 caused semi‐male sterility,resulting in reduction of grain yield in rice

OsSPX1, a rice SPX domain gene, involved in the phosphate (Pi)‐sensing mechanism plays an essential role in the Pi‐signalling network through interaction with OsPHR2. In this study, we focused on the potential function of OsSPX1 during rice reproductive phase. Based on investigation of OsSPX1 antisense and sense transgenic rice lines in the paddy fields, we discovered that the down‐regulation of OsSPX1 caused reduction of seed‐setting rate and filled grain number. Through examination of anthers and pollens of the transgenic and wild‐type plants by microscopy, we found that the antisense of OsSPX1 gene led to semi‐male sterility, with lacking of mature pollen grains and phenotypes with a disordered surface of anthers and pollens. We further conducted rice whole‐genome GeneChip analysis to elucidate the possible molecular mechanism underlying why the down‐regulation of OsSPX1 caused deficiencies in anthers and pollens and lower seed‐setting rate in rice. The down‐regulation of OsSPX1 significantly affected expression of genes involved in carbohydrate metabolism and sugar transport, anther development, cell cycle, etc. These genes may be related to pollen fertility and male gametophyte development. Our study demonstrated that down‐regulation of OsSPX1 disrupted rice normal anther and pollen development by affecting carbohydrate metabolism and sugar transport, leading to semi‐male sterility, and ultimately resulted in low seed‐setting rate and grain yield.     

枸杞色素及多糖的不同提取次序对其得率及抗氧化活性的影响

为探究先后提取枸杞多糖及枸杞色素时对各自得率的影响。本研究通过分别考察这两种成分在提取过程中的提取溶剂、提取温度、料液比、提取次数及提取时间等因素对枸杞色素和枸杞多糖的得率影响,确定枸杞色素和枸杞多糖在提取次序不同时,两者的最佳提取工艺以及对DPPH·和·OH自由基清除率。结果表明,首先提取枸杞多糖后,枸杞色素的最佳提取工艺为采用正己烷,80℃时,料液比1∶10,提取2次,每次1 h,枸杞色素得率为2.48%,此时枸杞多糖得率为7.45%;而首先提取枸杞色素后,采用了超声辅助提取的方式提取枸杞多糖,发现超声效率为25%,料液比1∶10,提取20 min,枸杞多糖得率为5.23%,此时枸杞色素得率为3.93%。因此,首先提取枸杞多糖,使其平均得率为7.45%,而后提取枸杞色素,其平均得率为2.48%;总体上,枸杞色素1和枸杞多糖1对DPPH·自由基清除率都较高,枸杞多糖1对·OH自由基清除率较高,其抗氧化活性都接近Vc。     

Hypoglycemic and hypolipidemic effects and antioxidant activity of fruit extracts from Lycium barbarum

The hypoglycemic and hypolipidemic effects of Lycium barbarum fruit water decoction, crude polysaccharide extracts (crude LBP), and purified polysaccharide fractions (LBP-X) in alloxan-induced diabetic or hyperlipidemic rabbits were investigated through designed sequential trials and by measuring blood glucose and serum lipid parameters. Total antioxidant capacity was also assessed using trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assay. It was found that the three Lycium barbarum fruit extracts/fractions could significantly reduce blood glucose levels and serum total cholesterol (TC) and triglyceride (TG) concentrations and at same time markedly increase high density lipoprotein cholesterol (HDL-c) levels after 10 days treatment in tested rabbits, indicating that there were substantial hypoglycemic and hypolipidemic effects. Hypoglycemic effect of LBP-X was more significant than those of water decoction and crude LBP, but its hypolipidemic effect seemed to be weaker. Total antioxidant capacity assay showed that all three Lycium barbarum extracts/fractions possessed antioxidant activity. However, water and methanolc fruit extracts and crude polysaccharide extracts exhibited stronger antioxidant activity than purified polysaccharide fractions because crude extracts were identified to be rich in antioxidants (e.g., carotenoids, riboflavin, ascorbic acid, thiamine, nicotinic acid). Lycium barbarum polysaccharides (glycocojugates), containing several monosaccharides and 17 amino acids, were major bioactive constituents of hypoglycemic effect. Both polysaccharides and vitamin antioxidants from Lycium barbarum fruits were possible active principles of hypolipidemic effect.