In Vitro Regeneration of Style-stigma-like Structure from Stamens of Crocus sativus

Style-stigma-like structures were regenerated from stamens of Crocus sativus L. The age of the stamen explant has an obvious effect on the induction rate. Auxin NAA. has larger effect on the induction of filament style-stigma-like structure. Auxin NAA of higher concentration can lead to higher induction rate. Temperature and light have different effects on the induction of style-stigma-like structure from anther's filament of C. sativus with exogenous hormones at different levels. Ultraviolet tests show that style-stigma-like structure from anther's filament of C. sativus contains crocin, safranal and picrocrocin, contents of which are obviously more than those contained in the style-stigma-like from style. Floral reversion was observed in the induction of style-stigma-like structure from petals, ovaries and styles.

Intrafloral differentiation of stamens in heterantherous flowers

Flowers that have heteromorphic stamens （heterantherous flowers） have intrigued many researchers ever since the phenomenon was discovered in the 19th century. The morphological differentiation in androecia has been suggested as a reflection of ＂labor division＂ in pollination in which one type of stamens attracts pollinators and satisfies their demand for pollen as food and the other satisfies the plant＇s need for safe gamete dispersal. The extent and patterns of stamen differentiation differ notably among taxa with heterantherous flowers. Seven species with heteromorphic stamens in three genera were sampled from Leguminosae and Melastomataceae, and the morphological difference of androecia, pollen content, pollen histochemistry and viability, pollen micro- morphology, as well as the main pollinators were examined and compared. Pollen number differs significantly between stamen sets of the same flower in most species investigated, and a correlation of pollen number and anther size was substantiated. Higher pollen viabilities were found in the long （pollinating） stamens of Senna alata （L.） Roxb. and S. bicapsularis （L.） Roxb. Dimorphic pollen exine ornamentation is reported here for the first time in Fordiophytonfaberi Stapf. The height of stigma and anther tips of the long stamens in natural conditions was proved to be highly correlated, supporting the hypothesis that they contact similar areas of the pollinator＇s body.

Regulation of Stamen Development by Coordinated Actions of Jasmonate, Auxin, and Gibberellin in Arabidopsis

Proper stamen development is essential for plants to achieve their life cycles. Defects in stamen development will cause male sterility. A vast array of research efforts have been made to understand stamen developmental processes and reg- ulatory mechanisms over the past decades. It is so far reported that phytohormones, including jasmonate, auxin, gibberellin, brassinosteroid, and cytokinin, play essential roles in regulation of stamen development. This review will briefly summarize the molecular basis for coordinated regulation of stamen development by jasmonate, auxin, and gibberellin in Arabidopsis.

Gibberellin and Jasmonate Crosstalk during Stamen Development

Gibberellin （GA） and jasmonate （JA） are two types of phytohormones that play important roles during stamen development. For example, Arabidopsis plants deficient in either of GA or JA develop short stamens. An apparent question to ask is whether GA action and JA action during stamen filament development are independent of each other or are in a hierarchy. Recent studies showed that GA modulates the expression of genes essential for JA biosynthesis to promote JA production and high levels of JA will induce the expression of three MYB genes MYB21, MYB24 and MYB57. These three MYB genes are crucial factors for the normal development of stamen filament in Arabidopsis.

A Gene Expression Profiling of Early Rice Stamen Development that Reveals Inhibition of Photosynthetic Genes by OsMADS58

Stamen is a unique plant organ wherein germ cells or microsporocytes that commit to meiosis are initiated from somatic cells during its early developmental process. While genes determining stamen identity are known according to the ABC model of floral development, little information is available on how these genes affect germ cell initiation. By using the Affymetrix GeneChip Rice Genome Array to assess 51 279 tran- scripts, we established a dynamic gene expression profile （GEP） of the early developmental process of rice （Oryza sativa） stamen. Systematic analysis of the GEP data revealed novel expression patterns of some developmentally important genes including meiosis-, tapetum-, and phytohormone-related genes. Following the finding that a substantial amount of nuclear genes encoding photosynthetic proteins are ex- pressed at the low levels in early rice stamen, through the ChlP-seq analysis we found that a C-class MADS box protein, OsMADS58, binds many nuclear-encoded genes participated in photosystem and light reac- tions and the expression levels of most of them are increased when expression of OsMADS58 is downre- gulated in the osmads58 mutant. Furthermore, more pro-chloroplasts are observed and increased signals of reactive oxygen species are detected in the osmads58 mutant anthers. These findings implicate a novel link between stamen identity determination and hypoxia status establishment.

The chromatin remodeling complex imitation of switch controls stamen filament elongation by promoting jasmonic acid biosynthesis in Arabidopsis

Plant reproduction requires the coordinated development of both male and female reproductive organs.Jasmonic acid(JA)plays an essential role in stamen filament elongation.However,the mechanism by which the JA biosynthesis genes are regulated to promote stamen elongation remains unclear.Here,we show that the chromatin remodeling complex Imitation of Switch(ISWI)promotes stamen filament elongation by regulating JA biosynthesis.We show that AT-Rich Interacting Domain 5(ARID5)interacts with CHR11,CHR17,and RLT1,several known subunits of ISWI.Mutations in ARID5 and RLTs caused a reduced seed set due to greatly shortened stamen filaments.RNA-seq analyses reveal that the expression of key genes responsible for JA biosynthesis is significantly down-regulated in the arid5 and rlt mutants.Consistently,the JA levels are drastically decreased in both arid5 and rlt mutants.Chromatin immunoprecipitationquantitative PCR analyses further show that ARID5 is recruited to the chromatin of JA biosynthesis genes.Importantly,exogenous JA treatments can fully rescue the defects of stamen filament elongation in both arid5 and rlt mutants,leading to the partial recovery of fertility.Our results provide a clue how JA biosynthesisis positively regulated by the chromatin remodeling complex ISWI,thereby promoting stamen filament elongation in Arabidopsis.

Stamen specification and anther development in rice

Male reproductive development is a complex biological process which includes the formation of the stamen with differentiated anther tissues, in which microspores/pollens are generated, then anther dehiscence and subsequently pollination. Stamen specification and anther development involve a number of extraordinary events such as meristem transition, cell division and differentiation, cell to cell communication, etc., which need the cooperative interaction of sporophytic and gametophytic genes. The advent of various tools for rice functional gene identification, such as complete genome sequence, genome-wide microarrays, collections of mutants, has greatly facilitated our understanding of mechanisms of rice stamen specification and anther development. Male sterile lines are critical for hybrid rice breeding, therefore understanding these processes will not only contribute greatly to the basic knowledge of crop developmental biology, but also to the development of new varieties for hybrid rice breeding in the future.

青皮竹花形态结构与雌、雄配子的发育研究

[目的]揭示青皮竹自然条件下不同发育阶段花器官的形态及其雌、雄配子体的解剖结构特征。[方法]采用形态解剖及石蜡制片的方法对青皮竹花器官的各部分外观形态特征以及雌、雄配子体的发育过程进行观察与描述。[结果]青皮竹小穗为无限花序,下部的小花先发育,但因小穗基部具有潜伏芽,因此又具有有限花序的特征。每个小穗约有8~10朵小花,顶端小花不育,小穗基部含有2~3枚黄棕色苞片。每朵小花均有内、外稃各1枚,浆片3枚,雄蕊6枚,雌蕊1枚。雌雄异熟,异花授粉。子房呈花瓶状,下部光滑不具棱,上部有绒毛。子房1室,侧膜胎座,倒生胚珠,双珠被。短花柱长柱头,花柱具绒毛,三分枝羽状柱头。花药呈黄色,4药室。未成熟的花药的花药壁由外向内依次为表皮、药室内壁、中层和绒毡层。绒毡层为腺质型,花药成熟后绒毡层退化,仅剩表皮和纤维层。花粉成熟后2或3核花粉粒,花药壁纵裂散粉。[结论]青皮竹花器官形态与解剖结构发育正常,而雌、雄配子体发育过程中出现多种败育情况,可能是青皮竹结实率低的重要原因。

阳春砂茉莉酸生物合成酶基因鉴定与时空表达分析

为探究阳春砂(Amomum villosum)花器中茉莉酸(JA)生物合成酶基因表达与雌雄蕊生长的关系,本研究利用cDNA末端快速扩增(RACE)技术克隆阳春砂JA生物合成酶基因的全长序列,并对各基因进行生物信息学分析、表达模式测定及各基因表达与阳春砂雌雄蕊生长的相关性分析,以探究阳春砂花器中JA生物合成酶基因表达与雌雄蕊生长的关系。结果表明,阳春砂中JA生物合成酶基因AvLOX、AvAOS、AvAOC、AvOPR3序列全长分别为2733、1798、930、1400 bp,分别包含2577、1485、744、1179 bp的开放阅读框(ORF),其编码蛋白分别含有858、494、247、392个氨基酸残基。4个JA生物合成酶基因的表达随阳春砂雄蕊的发育进程逐渐增加,但在雌蕊中的表达则呈现多样性。在雌蕊中,AvLOX、AvAOS基因在开花后1天表达最高,AvAOC在标记后第9天表达最高,AvOPR3基因在标记后第6天表达最高。除AvAOS基因在小花在标记后第3天以及AvOPR3基因在小花标记后第6天外,4个JA生物合成酶基因在雄蕊中的表达在各发育阶段显著高于同时期在雌蕊中的表达。与对照组相比,在喷施茉莉酸甲酯(MeJA)后,4个JA生物合成酶基因在雄蕊中的表达模式,以及AvLOX和AvOPR3基因在雌蕊中的表达模式没有改变,但AvAOS和AvAOC基因在雌蕊中的表达模式有变化。在对照组和MeJA处理组中,4个JA生物合成酶基因的表达与阳春砂小花花丝和花柱的长度有极显著的相关性。本研究结果为进一步探究JA与阳春砂花器官生长发育的关系奠定了基础。

金鱼草KNOX基因家族鉴定及调控其雄蕊瓣化的候选基因挖掘

【目的】KNOX(KNOTTED1-like homeobox)转录因子家族在植物生长发育及花器官发育中发挥重要作用。文章旨在鉴定并分析金鱼草(Antirrhinum majus)KNOX转录因子,挖掘出调控金鱼草雄蕊瓣化的关键候选基因。【方法】采用生物信息学方法,在金鱼草全基因组水平鉴定AmKNOX基因,并对其基因结构、蛋白理化性质、亚细胞定位、系统进化关系、染色体定位、启动子顺式作用元件及转录因子结合位点等进行分析,并利用金鱼草雄蕊瓣化和非瓣化材料进行RNA-seq分析和qRT-PCR验证,挖掘出候选基因。【结果】从金鱼草中共鉴定出11个AmKNOX基因,都具有KNOXⅠ、KNOXⅡ、ELK和HOX 4个相对保守的区域,分为ClassⅠ(AmKNOX1、AmKNOX2、AmKNOX3、AmKNOX9和AmKNOX11)和ClassⅡ(AmKNOX5、AmKNOX4、AmKNOX7、AmKNOX10、AmKNOX6和AmKNOX8)2类。AmKNOXs蛋白包含282~406个氨基酸,均定位于细胞核中。启动子顺式作用元件分析结果显示,AmKNOXs家族成员可参与植物生长、激素和非生物胁迫响应,且AmKNOXs存在大量与植物生长发育、器官分化和逆境生理调节相关的转录因子结合位点。RNA-seq和qRT-PCR分析表明AmKNOX家族基因在金鱼草正常雄蕊和瓣化雄蕊中显著差异表达。【结论】本研究共鉴定出11个AmKNOX成员,最终挖掘出5个正向(AmKNOX5、AmKNOX10、AmKNOX6、AmKNOX4和AmKNOX9)以及1个负向(AmKNOX11)调控雄蕊瓣化的AmKNOX候选基因。其中AmKNOX5基因在瓣化雄蕊中的表达量比正常雄蕊中高2703%,推测其功能非常重要,该研究为后期深入解析金鱼草花型发育分子机制和遗传改良奠定了基础。

RcAGL61基因调控雄蕊和花瓣之间转变影响月季花瓣数量

[目的]为探究月季重瓣性状的调控机制,研究克隆了前期筛选到的1个与花发育相关的AG同源基因RcAGL61,并对其功能进行分析。[方法]用荧光定量对该基因在‘窄叶藤本月季花’ב月月粉’杂交群体中重瓣株系和单瓣株系花芽5个发育时期的表达模式进行分析,以重瓣株系和单瓣株系为材料,克隆RcAGL61,并进行生物信息学分析、亚细胞定位及VIGS实验。[结果](1)该基因表达水平在单瓣株系的5个发育时期均显著高于重瓣株系,在单瓣株系花发育的S4-S5期比S1-S3期表达量明显升高。(2)RcAGL61编码区序列在单瓣株系和重瓣株系中一致,长度为495 bp,与RcAG基因序列相似度为30.75%,编码164个氨基酸,含有1个MADS-box保守结构域,属于MADS-Box基因家族。(3)RcAGL61蛋白定位于烟草表皮细胞的细胞核。(4)沉默该基因后,瓣化雄蕊数量增加,雄蕊数量减少,花瓣数量增加,萼片数量和雌蕊数量无显著变化。[结论]RcAGL61参与调控雄蕊原基和花瓣原基间的转变,影响月季的花瓣数量。

13个紫薇品种花粉形态及花粉活力分析

【目的】研究紫薇品种间的花粉形态特征及花粉活力差异,为后续紫薇品种杂交育种工作提供理论参考。【方法】通过扫描电子显微镜对13个紫薇品种的雄蕊群花粉粒表面形态特征进行观察研究,每个品种随机选取10粒花粉进行统计分析,同时利用固体培养基对13个紫薇品种的花粉活力进行测定。【结果】13个紫薇品种长短雄蕊花粉粒均呈长球形,有3条萌发沟,裂至接近两极,萌发沟间未连接,在极面观花粉粒呈钝三角形,均属于N3P4C5型花粉。紫薇品种间花粉粒外壁纹饰、极轴长、赤道轴长、萌发沟特征及花粉粒体积大小均差异显著,其中花粉大小为538.91~1402.40μm^(2),极轴长为30.51~46.31μm,赤道轴长为17.35~31.49μm,萌发沟长为18.38~34.36μm,萌发沟脊宽为5.72~11.34μm。花粉外壁主要包括孔穴状、脑皱状及皱波状3种纹饰,13个试验品种长雄蕊花粉粒相比于短雄蕊花粉粒,其花粉粒表面更为光滑饱满。花粉活力测定结果以‘紫精灵’紫薇花粉活力最强,花粉活力为93.94%,其中‘湘韵’紫薇为不育品种,其不育类型表现为雄性不育,花粉不萌发。【结论】紫薇不同品种的花粉粒形态特征和花粉粒表面纹饰可以作为紫薇品种分类鉴定的参考指标之一,本试验中的13个紫薇品种除不育品种‘湘韵’紫薇外,其他试验品种表现出较高的花粉活力,均可作为紫薇品种杂交育种工作材料。

3种生长调节剂对紫斑牡丹开花及枝条生理特性的影响

【目的】探讨3种生长调节剂处理对紫斑牡丹开花及枝条生理特性的影响,为其开花性状化学调控提供理论依据。【方法】以甘肃省兰州市榆中县官滩沟紫斑牡丹培育基地的‘象牙白’为材料,在花芽分化前分别叶面喷施100,300,500 mg/L的IAA、GA3和6-BA,以清水为对照,考察植株盛花期开花情况以及枝条抗氧化酶活性和渗透调节物质含量等生理指标变化。【结果】与对照相比,3种生长调节剂均能不同程度增加紫斑牡丹开花数和重瓣率,且500 mg/L 6-BA处理效果最好,其单、重瓣花枝条的SOD、POD活性及脯氨酸含量也最高。紫斑牡丹枝条中SOD、POD和CAT活性与植株开花数和重瓣率均呈正相关,在开花过程中发挥着不可忽视的作用,并以SOD表现更为突出。3种生长调节剂处理紫斑牡丹开花数、重瓣率及枝条各项生理指标分别在500 mg/L 6-BA、500 mg/L GA3及300 mg/L GA3处理下表现最佳。【结论】3种生长调节剂均通过枝条生理指标直接或间接促进增加紫斑牡丹开花数和雄蕊瓣化程度,但促进程度存在差异,其中以500 mg/L 6-BA处理的开花数和重瓣率增幅最大。

早春不稳定传粉环境中新疆郁金香混合交配系统中的自交策略

[目的]在不确定传粉环境中,两性花植物常常具有潜在自交能力,鉴于自交的交配代价,进行不同环境下自交策略研究,对深入理解植物交配系统的演化具有重要意义。[方法]以早春短命植物新疆郁金香为研究对象,通过野外观测及人工控制试验对自然居群的开花习性、传粉者类群、散粉动态、自花粉传递模式和交配系统等进行研究,以探讨早春不稳定传粉环境中植物的自交策略。[结果](1)新疆郁金香自然种群4月上旬或中旬开花,单花期5~6 d,白天开放晚上闭合,花粉的释放从外轮开始,由下到上呈拉链式次序呈现。(2)传粉者主要为蜂类和食蚜蝇,访花频率普遍较低,且年份间存在较大差异,但结实率普遍较高。(3)控制授粉试验表明,居群为异交为主,部分自交亲和的混合性交配系统。傍晚花闭合时雄蕊的自主运动促进了柱头的自花授粉,这一传粉模式促进了竞自交的发生,但大量自花粉的落置发生在开花后的第4天,占自花粉总落置量的50.22%,为一种延迟自交机制。[结论]在传粉受限的情况下,新疆郁金香的竞自交和延迟自交促进柱头的花粉落置,这种集异交、竞自交和延迟自交为一体的交配策略灵活地应对了早春不稳定的传粉环境,是对早春低温度条件下不确定传粉服务的一种适应,也是早春短命植物的一种繁殖保证对策。

滇牡丹雄蕊提取物的化学成分、体外抗氧化和护肤活性研究

为深入分析滇牡丹不同颜色雄蕊的化学成分和生物活性,该文选取滇牡丹的不同发育阶段(透色期、初开期和盛开期)的红色和黄色雄蕊为材料,采取不同体积分数(0%、50%、80%、100%)的乙醇水溶液对其进行提取,测定不同颜色和不同发育阶段的雄蕊提取物的总黄酮和总酚含量;以DPPH自由基和ABTS阳离子自由基清除能力、铁还原力为指标,考察其体外抗氧化活性;以酪氨酸酶抑制活性和弹性蛋白酶抑制活性为指标,评估其护肤活性,并采用高效液相色谱法分析其化学成分。结果表明,当乙醇体积分数为50%时,滇牡丹雄蕊的总酚和总黄酮提取率及其含量最高,抗氧化活性、酪氨酸酶抑制活性和弹性蛋白酶抑制活性最强。整体而言,滇牡丹雄蕊的化学成分、体外抗氧化和护肤活性随其发育阶段动态累积和增强,以盛开期的最佳,且滇牡丹中红色雄蕊的化学成分和生物活性要优于黄色雄蕊。采用高效液相色谱从滇牡丹雄蕊提取物中鉴定出11个化合物,其中芍药苷、山奈酚、芦丁、槲皮素、儿茶素为滇牡丹雄蕊的主要酚类物质。该文可为滇牡丹不同颜色雄蕊在抗氧化、抗皱美白等方面的开发利用提供一定的理论依据。

文冠果雄蕊发育的解剖学及雄性不育蛋白的研究

研究文冠果雄性不育机理 ,该文观察了文冠果雄蕊发育的形态及解剖结构 ,并通过双向电泳方法对花药蛋白进行差异分析 .结果表明 :①两性花花药和雄花长、短花丝花药中均含有具萌发能力的花粉粒 ,但两性花的饱满花粉粒比雄花的饱满花粉粒少 ,两性花花粉败育可能发生在双核花粉粒时期 ;②雄花的短花丝后期能伸长 ,花药能正常开裂散粉 ,而两性花的花丝始终不伸长 ,花药不能开裂 ,这表明文冠果雄性不育的症结主要在于花药不能正常开裂 ,其次在于部分花粉败育 ;③在蕾期 ,两性花花药蛋白与雄花花药蛋白无差异 ;至开花期 ,至少有 2个多肽(B1 ,B2 )的表达存在差异 .对B1 进行了纯化和测序 ,序列为AGSDDVKVPIHPGSG .经蛋白质数据库检索 ,尚无与之同源的序列 .

毛细管电泳紫外检测法测定莲须中的槲皮素、木犀草素、山萘酚、异槲皮甙

采用毛细管区带电泳紫外检测法(CZE-UV)同时测定中药莲须中槲皮素、木犀草素、山萘酚、异槲皮甙4种有效成分。研究了缓冲溶液的离子浓度、pH值和电压对分离度和迁移时间的影响,得到了最佳分离实验条件。在离子浓度为40mmol/LNa2B4O7缓冲溶液(pH9.0)中,分离电压为16kV,波长为254nm时,槲皮素、木犀草素、山萘酚、异槲皮甙4种物质在10min内得到了良好的分离测定,其检出限分别为5.0、6.7、4.5和6.0mg/L。本方法应用于实际样品的测定,结果令人满意。

白桦花芽RNA的快速提取

酚类化合物、多糖、蛋白质和未知次级代谢产物,是影响白桦（BetuLa pLatyphyLLa）花芽组织RNA提取的几个主要干扰因素。笔者在以往草本植物DNA和微生物RNA提取方法基础上,提出了提取白桦雄花芽组织RNA的3种方法。

水稻雄蕊雌蕊化突变体的遗传分析

在杂交育种后代中发现了一个水稻雄蕊雌蕊化突变体 ,表现为 :外颖和内颖变窄 ,外颖弯曲呈弯月形 ,内外颖不闭合 ,1～5枚雄蕊转变为雌蕊或雌蕊 雄蕊嵌合体。由于高度雌性不育 ,突变纯合体本身无繁殖保持功能 ,只能通过杂合体繁衍 ,在自交 15代后仍分离出完全相同的突变体 ,表现稳定遗传特性。遗传分析表明该突变体由单隐性基因控制。

高温对设施甜樱桃花器官发育的影响

【目的】探讨花芽萌动期短时间高温处理对设施甜樱桃花器官发育的影响。【方法】以人工气候室中培养的4年生盆栽‘红灯’甜樱桃为试材,于花芽萌动期雄蕊发育的不同阶段进行短时间高温处理后,观察对花器官发育、花器官外观表现和花期的影响。【结果】设施甜樱桃花芽萌动期不同阶段的4 h 35℃高温处理对雌、雄生殖器官发育和花期花器官表现都有显著影响。较早高温处理对雄蕊发育的抑制程度强于雌蕊,花期雄蕊变褐率极显著增加,甚至会导致雄蕊完全败育,花期明显变短;越临近花期的高温处理,花期雌蕊枯萎率和花冠卷曲率明显高于其它处理,并且对始花期促进作用越明显;不同阶段短时间高温处理后都未发现大孢子产生和分化异常。【结论】甜樱桃花芽萌动期的雌、雄生殖器官发育过程中对短时间高温胁迫的敏感时期和敏感性不同。