新疆阿魏的胚胎学研究

采用常规石蜡制片技术,对新疆阿魏不同发育时期的花和果实进行了显微切片观察.结果表明:新疆阿魏小孢子母细胞的减数分裂为同时型,小孢子四分体为四面体型和十字交叉型,成熟花粉粒为3-细胞型.雌蕊2心皮合生成2室,中轴胎座,每子房室内产生上、下2个胚珠原基,其中,下方的原基正常发育,而上方的原基停止发育并最终解体,因此,每室仅产生一枚发育正常的倒生胚珠,单珠被,薄珠心,胚囊发育为蓼型;珠被绒毡层和珠孔塞发生于大孢子四分体时期,并于四核胚囊时分化完全,八核胚囊时珠被绒毡层细胞径向延长;3个成熟的反足细胞具双核.胚乳发育为核型,细胞壁较厚,细胞排列紧密,可保护胚免受机械损伤及防止胚失水.胚乳细胞中含有大量PAS染色呈正反应的物质,一些胚乳细胞异常生长形成细胞体积大、核及核仁均较大的巨形细胞.胚胎发生为茄型,四细胞原胚为直线形,十六细胞原胚的顶部由2排各4个细胞组成.成熟种子具胚乳.     

拯救新疆阿魏

在众多读者来信中,我们被这样一封诚挚的"拯救新疆阿魏"的来信吸引了。新疆阿魏,一种对大多数人而言陌生的植物,也许在更多人认识它之前,它就因为人类的无知与自私,彻底消失在人们的视线中了。我们在这里刊出这封来信,希望能引起广大读者的共鸣,植物环境是人类赖以生存的基础,我们要真正关心自己生存的空间,就从关心那些需要我们保护的植物开始吧。     

阿魏传粉昆虫及其访花行为的初步研究

对新疆阿魏访花昆虫种类、昆虫访花频次、昆虫访花时间及昆虫访花行为进行了初步研究。在盛花期观察中,(1)发现有5目、23科、45种昆虫进行了访花,其中传粉昆虫4科7种,均属蜜蜂总科;(2)各类昆虫访花频次在不同观察时间变化较大,传粉蜜蜂仅出现在其中一个观察日中;(3)不同种类昆虫在花上的停留时间差异很大,传粉昆虫停留时间很短,鞘翅目昆虫停留时间最长。进入始果期后,昆虫的访花行为是围绕花盘的蜜腺展开的。     

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.     

甘蓝型油菜几个雄性不育系花药发育的细胞形态学研究

选用甘蓝型油菜6个细胞质雄性不育系和1个细胞核雄性不育系为材料,与可育系比较,确定花药发育受阻的时期和方式。根据研究结果,将其雄性不育系分为三类:1.湘矮A,Po-aA,陕2A和7s-3A花药发育受阻于孢原细胞分化期,没有分化形成花粉囊。2.萝AⅠ和萝AⅡ花药发育受阻于四分体至单核花粉期。败育方式为小孢子难以从四分体中释放出来,或释放出来后细胞质液泡化,核不能分裂,花粉壁发育不良。此外,还见到绒毡层径向肥大、延迟消失和维管束分化不良等异常现象。3.宜3A为核不育系,花药发育受阻于花粉母细胞期。败育方式为花粉母细胞死亡,减数分裂异常,或不能进行减数分裂。绒毡层和维管束一般都能正常发育。     

新疆阿魏内生真菌菌群多样性

【目的】探索新疆阿魏植物内生真菌的分离方法,了解其状况,为进一步深入研究其作用机理及应用价值提供基础。【方法】采用微生物学研究方法与技术,对新疆阿魏不同年份、不同部位的内生真菌进行了分离鉴定。通过分离率、分离频率、Shannon-Wiener多样性指数和Margalef丰富度指数等分析新疆阿魏内生真菌的分布、多样性及偏好性。【结果】本研究共分离得到内生真菌140株,经形态和分子生物学鉴定分别归属于18个属,其中,短梗霉属、链格孢属和叶点霉属为优势菌群,分别占总菌株数量的25.7%、16.4%和15.7%。不同年份的新疆阿魏中1-2年生新疆阿魏的Shannon-Wiener多样性指数(H’)和均匀度指数最高,分别为1.12和0.51,开花年份新疆阿魏的丰富度指数最高,为1.40;不同组织的新疆阿魏中,根的三项多样性指标最高,分别为1.27、1.26和0.55。此外,不同年份新疆阿魏中1-2年和3-4年生新疆阿魏中内生真菌菌群相似性系数最大,达到0.63;不同组织新疆阿魏中则以叶与茎中的相似性系数稍高,达到0.50。【结论】新疆阿魏不同年份及不同部位中的内生真菌分布及组成存在较大差异,具有一定的年份及组织的专一性。     

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.     

大白菜雄性不育系88—3花药和花粉发育的细胞形态学观察

大白菜雄怀不育两用系88－3的不育株,其开花时花药内无花粉粒,败育从小孢子母细胞至二核花粉粒皆有发生,高峰期在末期Ⅱ前后,小孢子母细胞不能进入减数分裂和小孢子母细胞不能完成减数分裂及孢子不能正常发育是雄性败育的主要形式;败育一旦发生便是急剧而彻底地解体或凝聚成一团是败育的共同点,中层组织、绒毡层组织及药隔维管束异常均是雄性败育的因素。     

新疆阿魏中总黄酮的提取分离及含量测定

以芦丁为对照品,NaNO2-AlCl3-NaOH体系为显色剂分光光度法测定新疆阿魏的总黄酮类含量。通过回流法和超声法提取新疆阿魏中的总黄酮,比较两种提取方法,从而得到最佳的提取方法,超声法是合适的提取方法。确定了提取总黄酮的适当溶剂、时间和显色剂用量。建立了芦丁浓度-吸光度关系的回归方程为A=9．2500C-0．0193,r=0．9993。平均回收率为98．73％。RSD为1．04％（n=6）。方法简单、可行、重现性好。     

药用类短命植物新疆阿魏花蜜腺的发育解剖学研究

类短命植物新疆阿魏(Ferula sinkiangensts K.M.Shen),是新疆独具特色的药用蜜源植物,其花蜜腺位于下位子房的花盘之上,由子房上部的表层细胞特化而形成的,属下位子房上的盘状蜜腺.但由于其花柱短,基部呈圆锥状,蜜腺分布于盘状结构表面除花柱外的区域,因而可以认为是花柱基部类蜜腺的一种扩展和特化,属于从子房蜜腺向花柱蜜腺过渡的类型.在蜜腺下方分布有大量的子房维管束,其泌蜜途径可能为:前蜜汁经共质体或非共质体途径到产蜜组织中,加工后再经共质体途径运进气孔下方的特殊细胞中,再分泌到孔下室,经气孔泌出.其花蜜腺在发育过程中液泡化动态明显,PAS反应测试细胞具阳性物质,淀粉粒积累动态较明显.     

‘马哈利’樱桃雄性不育细胞学观察

运用常规石蜡切片技术,以‘马哈利’樱桃雄性不育株和可育株的花芽为试验材料,对其小孢子和雄配子体的发育过程进行观察研究,运用扫描电镜对其花药和花粉进行观察,并分析‘马哈利’樱桃雄性不育的花粉发育过程及其发生原因。结果显示:(1)不育株与可育株的花粉发育形态在花粉母细胞时期没有差别,均可形成正常四分体。(2)四分体时期之后,不育株的绒毡层细胞膨大并向药室中央挤压,接着与小孢子粘连在一起,小孢子因得不到发育所需要的物质和空间而和绒毡层一起降解消失。(3)扫描电镜观察表明:不育株花药和花粉均呈现干瘪萎缩的形状,可育株花药四腔形状明显,花粉清晰可见萌发沟。研究表明,马哈利樱桃种内存在雄性不育系类型,‘马哈利’樱桃雄性不育与绒毡层细胞异常膨大和提前程序性死亡有关,进而造成了小孢子的异常发育并发生败育现象,研究结果对于樱桃杂交育种亲本选择以及樱桃苗木繁育生产具有重要的理论指导意义。     

辣椒雄性不育系与可育系小孢子发生的细胞学观察

为了探讨辣椒雄性不育花药败育时期和方式,以辣椒雄性不育系1442A、13733A及其可育系为试材,进行了研究。结果发现：败育现象从造孢细胞时期以后每个阶段都有发生,败育形式有造孢细胞液泡化、畸形、拉长、细胞间隙大;绒毡层细胞径向过度伸长,高度液泡化,且出现多层细胞,严重挤压小孢子母细胞,解体较晚且充塞花粉囊室;薄壁细胞取代了药室内壁、中层、绒毡层和小孢子母细胞的分化;药室内壁、中层层数增加,绒毡层细胞肥大,造孢细胞或花粉母细胞分解解体;由于花粉母细胞胼胝质壁不降解而无法释放出四分体小孢子;染色浅、细胞质被降解成空壳的单核期小孢子因缺乏营养物质而败育。     

Proteomic approach for investigation of cytoplasmic male sterility (CMS) in Brassica

The alloplasmic ‘Tournefortii’ CMS system fromB. napus was chosen for a comprehensive investigation of the protein content of the mitochondrial compartment in male sterile and fertile near isogenic lines. As proteins involved in the male sterile phenotype may be expressed in a tissue-specific manner, mitochondrial preparations were made from different tissues and checked for the purity of the organelles with a new and highly sensitive method (BN-PAGE). InBrassica, only mitochondrial preparations from 4-5-day-old seedlings and from flower buds were found to be sufficiently pure. High resolution, two-dimensional gel electrophoresis of total protein from anthers and from mitochondrial protein of male sterile and fertile seedlings of near isogenic lines revealed distinct differences in the protein patterns. Several explanations for the occurrence of these differences, which may be the starting point for a detailed molecular analysis and a better understanding of the CMS syndrome, are discussed.     

TheBrassica mitochondrial DNA plasmid and large RNAs are not exclusively associated with cytoplasmic male sterility

Summary More than 100 differentBrassica nucleo-cytoplasmic combinations were analysed for the presence or absence of the 11.3 kb mitochondrial plasmid. Contrary to some previous reports, no close association exists between the presence of the plasmid and cytoplasmic male sterility. Some novel abundant RNAs which copurified withBrassica mitochondria are described.     

杜鹃花属植物杂交不亲和与败育分布研究

该研究以杜鹃花属5亚属3组17亚组38种,计109个不育组合及91个可育组合的杂交结果为依据,对4个杂交不亲和指标与败育系数及败育频度参数进行了分析。结果表明:(1)杜鹃花属不同类群间杂交的不育组合比例约为54.5%,其不亲和与败育包括不能坐果(capsul aborted,Cab型)、坐果但不能形成种子(seed aborted,Sab型)和能形成种子但不能发芽(seed not germinated,Sng型) 3种情况,其中Cab与Sab类型均可能是前合子期不亲和与后合子期不亲和的复合表征,Sng型则可以肯定为后合子期种子发育阶段败育的情况,Cab∶Sab∶Sng=81∶13∶15;而可育组合中部分败育苗无疑属于"杂种不活hybrid inviability"的败育类型。(2)有关不育类型的分布与杜鹃花属植物亲本类群及其分类与亲缘关系具有明显关联,从同一亚组内、同一亚属内到不同亚属间杂交的不育类型的分布呈Sng型→Sab型→Cab型增加的趋势,杂交双亲分类上亲缘关系越密切Sng型的频度越高,反之关系越疏远Cab型的频率越高,亚属间远交往往止于Cab型。(3)"杂种不活"为败育苗的表现形式之一,从同一亚组、同一亚属到不同亚属间杂交,其败育等级频度分布通常也从无或轻度败育到严重败育方向发展,常绿杜鹃亚属内杂交的败育情况明显低于杜鹃亚属内杂交,这与后者多倍体亲本的介入相关,而上述2亚属间杂交的苗木败育则更加严重,但映山红(R. simsii)分别与百合花杜鹃(R. liliiflorum)和毛肋杜鹃(R. augustinii)的亚属间杂交未出现败育苗分布。     

Expression of sunflower cytoplasmic male sterility-associated open reading frame, orf H522 induces male sterility in transgenic tobacco plants

Sterility in the universally exploited PET1-CMS system of sunflower is associated with the expression of orfH522, a novel mitochondrial gene. Definitive evidence that ORFH522 is directly responsible for male sterility is lacking. To test the hypothesis that ORFH522 is sufficient to induce male sterility, a set of chimeric constructs were developed. The cDNA of orfH522 was cloned in-frame with yeast coxIV pre-sequence, and was expressed under tapetum-specific promoter TA29 (construct designated as TCON). For developing control vectors, orfH522 was cloned without the transit peptide under TA29 promoter (TON) or orfH522 was cloned with or without transit peptide under the constitutive CaMV35S promoter (SCOP and SOP). Among several independent transformants obtained with each of the gene cassettes, one third of the transgenics (6/17) with TCON were completely male sterile while more than 10 independent transformants obtained with each of the control vectors were fertile. The male sterile plants were morphologically similar to fertile plants, but had anthers that remained below the stigmatic surface at anthesis. RT-PCR analysis of the sterile plants confirmed the anther-specific expression of orfH522 and bright-field microscopy demonstrated ablation of the tapetal cell layer. Premature DNA fragmentation and programmed cell death was observed at meiosis stage in the anthers of sterile plants. Stable transmission of induced male sterility trait was confirmed in test cross progeny. This constitutes the first report at demonstrating the induction of male sterility by introducing orfH522 gene that could be useful for genetic engineering of male sterility. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Cytoplasmic male sterility in Vicia faba L.

Summary In many higher plants, nucleo-cytoplasmic interactions lead to pollen abortion. In Vicia faba, cytoplasmic male sterility is unstable as the cytoplasm appears to shift from a sterile to a fertile state. In this report, five flower phenotypes are defined but the study is focussed on the progenies obtained from intermediate, semi-sterile plants with the same homozygous nuclear constitution during five successive generations. The results could be interpreted by quantitative modifications of at least four different kinds of cytoplasmic determinants.     

Inheritance of male sterility in Trifolium hirtum All

The inheritance of male sterility was studied using a set of intra and interpopulation crosses from Californian populations of rose clover (Trifolium hirtum All.). The F2 gave higher frequencies of male steriles in interpopulation crosses than in intrapopulation crosses. Several F2 families gave ratios that were compatible with models of two and three complementary genes. However, the frequency distribution of male sterility among F3 families rejected such models. Given that single and two gene models were rejected, we interpret the results using a cytoplasmic-nuclear model with more than two restorer loci which is at least consistent with the observed results.     

Cytoplasmic male sterility in barley

Summary Restoration in the msm1 cytoplasm of barley (Hordeum vulgare L. s.l.) was studied from the standpoint of population biology and physiological effects on kernel protein. Restorer genes of 82 accessions of wild barley (ssp. spontaneum) from Israel were determined. 38% of the accessions were maintainers of sterility, 48% were partial restorers, and 14% were restorers. Fourteen dominant restorer genes are described, and evidence for three cases of allelism to Rfm1a is presented. The restorer accessions and their designated gene symbols are: PI 282636 (Rfm,,e), PI 282637 (Rfm,f), PI 282646 (Rfm,,g), PI 284742 (Rfm,h), PI 284743 (Rfm,,i), PI 284753 (Rfm,,j), PI 284755 (Rfm1d), PI 296838 (Rfm,,k), PI 296850 isolate 16/7 (Rfm,,l), PI 296853 (Rfm,,m), PI 296856 (Rfm1b), PI 296899 (Rfm,,n), PI 296919 (Rfm1c), PI 296944 (Rfm,,o). PI 296850 was found to contain both a restorer and a non-restorer genotype. None of the PI accessions with a restorer gene is a carrier of an msm1-type male sterilizing cytoplasm. In the present sample, plants with restoration ability occurred with a higher frequency in the material from the Judean Foothills than that from the other regions of Israel. The greater adaptive value of plants with restoration ability on certain soil associations in semiarid and subhumic climate is suggested. The considerable frequency of restorers and partial restorers in male fertile cytoplasm suggests that the restoration system evolved before the msm1-type cytoplasm. In the nuclear genotype near-isogenic with either Adorra or Risø 1508, msm1 plants heterozygous for Rfm1a produced 98.6 or 98.5% of the protein content in the respective recurrent pollen parent varieties. The amino acid compositions of the derivatives differed little from those of the varieties. In the derivatives, a consistent decrease was found in tryptophan, and consistent increases in isoleucine, phenyalanine, lysine, histidine, and arginine. In relation to glucose consumption, the bioenergetic cost calculated for the amino acid patterns found in the restored msm1 derivatives was slightly higher than that for the near-isogenic pollen parent varieties. The results suggest that the restorer gene in the heterozygous state normalizes the physiology of msm1 cytoplasm to a great extent.