菊花自交不亲和性初步研究

以菊花品种杂交为对照,通过自交亲和指数、受精作用及自交有性过程荧光显微镜观察,对菊花自交不亲和性进行了研究。结果表明:菊花自交难以结实,具不亲和性;菊花自交不亲和的反应部位在雌蕊柱头,表现为花粉粒粘附少、萌发率低及诱导胼胝质生成,花粉管在柱头上出现各种异常现象而难以进入花柱。     

白菜型油菜自交亲和性变异分析

对不同来源的85份白菜型油菜品种的自交亲和指数研究表明,白菜型油菜的自交亲和性存在较大幅度的变异,自交亲和指数在0．00～9．28之间,这种变异不仅存在于品种间,而且存在于品种内不同个体间。85份参试材料中,自交亲和指数小于1的有50个品种;35个品种自交亲和指数大于1,自交亲和指数在1．00～9．28之间,其中亲和指数大于4的材料有28、44、45、55x、75、119、123、139号品种等。依据自交亲和指数,可将参试材料分为4种类型:高自交亲和类型(自交亲和指数>4．00);自交亲和类型(自交亲和指数1．00～3．99);自交不亲和类型(0．00< 自交亲和指数<1．00);高自交不亲和类型(自交亲和指数=0．00)。自交亲和性因地区而异,一般西部地区的品种自交亲和性高于其它地区的品种。     

白芥自交亲和性分析

对不同来源的8份白芥材料,采用人工自交法分析其自交亲和性。结果显示:白芥的自交亲和性存在较大幅度的变异,自交亲和指数在0.01~4.10之间,8份参试材料中,自交亲和指数小于1的材料有3个,自交亲和指数大于1的材料有5个。表明白芥中存在自交亲和材料,白芥自交亲和性变异不仅存在于材料间,而且也存在于同一材料内不同个体间。按自交亲和指数的高低,可将参试材料分为3种类型:高自交亲和类型(自交亲和指数大于3.00,如民乐洪水芥麻、04(X)等)、自交亲和类型(自交亲和指数为1.00~2.99)、自交不亲和类型(自交亲和指数0.00~1.00)。     

植物的自交不亲和性

自交不亲和性(self-incompatibility)也叫自交不育性(self-sterility),指某些植物在自然条件下,虽然两性器官都正常,但以本花、本株或同一品种的异株花粉授粉时,不能受精或不能正常结实的现象.这种不亲和性常见于某些雌雄同株的植物,如黑麦以本穗花粉授粉,苹果和梨的某些品种以本株、本品种的花粉授粉时常不结实.自交不亲和是植物长期进化过程中所形成的有利于异花传粉的一种生殖隔离.它却给作物种子生产上带来了防杂保纯的困难.然而,认识这种特性的特点,采取相应措施,就可以发挥其长处,有利于农业生产.例如,大白菜育种上针对这一特性育成自交不亲和系,可以简化去雄手续,产生杂交种子,利用杂种优势.苹果、梨等果树中自交不结实或结实很少的某些品种,适当配置与主栽树同时开花、花粉发育正常、所结果实的经济价值也较高的品种作授粉树,可使主栽树有良好的授粉、受精条件,增加结果.如茌梨用鸭梨、青香蕉苹果用红香蕉苹果作授粉树等.     

植物自交不亲和性机理的研究

植物自交不亲和性机理的研究罗光明,杨雅琴（江西中医学院药学系植物室,南昌３３０００６）在自然条件下,任何植物在开花时,其雌性器官既可能接触种内的花粉,也可能同时接触异种的花粉,但是,只有具备一定遗传背景的个体之间才能实现亲和性的交配。在一般情况下,交...     

高等植物自交不亲和性的分子生物学

自交不亲和性是大多数高等植物防止近亲繁殖的一种遗传屏障。它涉及受精时雄配子（花粉）和雌蕊之间的相互作用。目前,已经分离获得了编码控制雌蕊自交不亲和性的Ｓ基因。在孢子体型自交不亲和的芸苔属中,雌蕊Ｓ基因编码Ｓ位点糖蛋白（ＳＬＧ）和Ｓ受体激酶（ＳＲＫ）。它们可能与磷酸化和去磷酸化参与了的某种信号传递有关,最后导致自交花粉生长的抑制。在配子分配体型自交不亲和的茄科中,雌蕊Ｓ位点糖蛋白为一种核糖核酸酶,称     

高等植物自交不亲和性的分子生物学

自交不亲和性是大多数高等植物防止近亲繁殖的一种遗传屏障。它涉及受精时雄配子（花粉）和雌蕊之间的相互作用。目前,已经分离获得了编码控制雌蕊自交不亲和性的Ｓ基因。在孢子体型自交不亲和的芸苔属中,雌蕊Ｓ基因编码Ｓ位点糖蛋白（ＳＬＧ）和Ｓ受体激酶（ＳＲＫ）。它们可能与磷酸化和去磷酸化参与了的某种信号传递有关,最后导致自交花粉生长的抑制。在配子分配体型自交不亲和的茄科中,雌蕊Ｓ位点糖蛋白为一种核糖核酸酶,称为Ｓ－核酸酶（Ｓ－ＲＮａｓｅ）。自交不亲和反应与Ｓ－核酸酶引起的花粉管ＲＮＡ降解有关,并且可能通过花粉管特异性地摄入Ｓ－核酸酶或者花粉管内存在的特异性的核酸酶抑制剂的作用,达到对自交花粉生长的抑制。另外,从配子体型自交不亲和的罂粟中,分离到了与芸台属和茄科不同的雌蕊Ｓ基因,其作用机理可能与Ｃａ＋＋参与的信号传递有关。     

植物自交不亲和性研究的文献计量学分析

运用文献计量学原理和方法,对１９９１～１９９５年间有关植物自交不亲和性研究的文献进行计量分析,揭示了其中的动态规律和此项研究的发展趋势。     

白菜自交不亲和性的荧光测定

通过亲和指数法及荧光显微观察对白菜的自交不亲和性进行了测定。结果表明,白菜自交不亲和的反应部位在柱头,自花授粉后柱头表面产生明显的胼胝质反应。两种观测法的结果相吻合,荧光显微镜观察法准确、方便,可应用于白菜自交不亲和系的育种实践。     

甘蓝自交不亲和性的化学控制

本文介绍甘蓝自交不亲和性的化学控制研究进展。     

Agrobacterium-mediated transformation of Eruca sativa

An Agrobacterium tumefaciens—mediated transformation system was developed for Eruca sativa (eruca). Hypocotyl explants were co-cultivated with bacterial cells carrying a plasmid harboring a uidA:nptII fusion gene along a phosphinothricin acetyl transferase (PAT) gene cassette, for a period of 2 days. These were grown on a high cytokinin/auxin medium containing 5.0 mg l^?1 6-benzyladenine (BA), 1.0 mg l^?1 indole-3-acetic acid (IAA), and 0.1 mg l^?1 α-naphthaleneacetic acid (NAA). Explants were then transferred to a lower cytokinin/auxin medium containing 2.0 mg l^?1 BA and 0.1 mg l^?1 NAA along with 5.0 mg l^?1 silver nitrate and 300 mg l^?1 Timentin®. Upon transfer to a selection medium containing either 20 mg l^?1 kanamycin or 2 mg l^?1 L-phosphinothricin (L-ppt), shoot regenerants were observed. Expression of the transgenes in putative transformants was confirmed using a histochemical GUS assay. Presence of the PAT transgene in GUS-positive T0 plants was confirmed by Southern blot analysis. Moreover, spot tests of T1 seedlings were conducted using the L-ppt herbicide. A transformation frequency of 1.1% was obtained with more than 60% of transgenic lines containing single copies of the transgenes.     

Variation in Biomass Properties among Rice Diverse Cultivars

Biomass properties of rice straws were compared among eight cultivars that formed a mini diverse set. The ethanol productivity from rice straws was evaluated employing a laboratory-scale method based on dilute acid-hydrolysis pretreatment. The results indicated significant variation in biomass properties among the cultivars.     

A Comovirus Infecting Rocket (Eruca sativa) in Brazil

A virus related to Radish mosaic virus and Turnip ringspot virus (TuRSV) was found infecting rocket plants in Brazil. Predicted amino acids from partial viral RNA sequences placed it closer to TuRSV. We describe here the identification and partial characterization of the first comovirus found infecting a crucifer species in Brazil.     

Quantification of the Effect of Environmental Factors on Seed Germination and Seedling Growth of Eruca (Eruca sativa) Using Mathematical Models

Eruca (Eruca sativa; Brassicaceae) is an important industrial crop due to its ability to grow under a wide range of climatic conditions and in poor fertility lands and also for the quality of seed oil and protein. Seed germination (SG) is an important event in plant’s life history which can significantly be influenced by several environmental factors such as temperature (T), water potential (ψ), salinity, pH, and burial depth. Therefore, this study aimed (i) to investigate the effects of these environmental factors on SG behavior of Eruca using several mathematical models, (ii) to determine the cardinal Ts and tolerance threshold value for each trait (i.e., 50% reduction than its maximum value) affected by the environmental factor, and (iii) to quantify the response of Eruca seedling growth to each environmental factor. The results indicated that Eruca SG and seedling growth were significantly influenced by these factors (P < 0.05). The estimated cardinal Ts were 1 °C for the base T, 30 °C for the optimum T, and 40.8 °C for the ceiling T. The salt and drought tolerance threshold values were 257 mM NaCl and − 1.2 MPa for SG and 247 mM NaCl and − 1 MPa for the seedling growth, respectively, suggesting that the seedling growth was more sensitive than SG under both salt and drought stresses in Eruca. In addition, the maximum SG and seedling growth were observed at pH 7 and burial depth 1.9 cm. In general, the models used in this study could describe well the response of Eruca SG under different levels of environmental factors and also their parameters could easily be used in Eruca SG simulation models. This information also could help us to better manage the production of this plant under stressful conditions and/or to determine its geographic range expansion in the world.

     

Variation in Preference for Rhizobium meliloti Within and Between Medicago sativa Cultivars Grown in Soil

Variation in nodulation preferences for Rhizobium strains within and between Medicago sativa cultivars was assessed in the greenhouse with plants grown in Leonard jars and two soils of diverse origin (Lanark and Ottawa), using inocula consisting of effective individual or paired strains of R. meliloti which could be recognized by high-concentration antibiotic resistance. The results indicated considerable variability in host preferences for R. meliloti among plants within cultivars but not between cultivars. The implications of this variation are discussed from the point of view of possible improvement of symbiotic nitrogen fixation. With one exception, the differences in nodulation success between inoculant R. meliloti strains were consistent in Leonard jars and both soils. All introduced strains formed significantly more nodules in Renfrew soil containing few native rhizobia than in Ottawa soil with a large resident R. meliloti population. Plants grown in Lanark soil without inoculation were ineffectively nodulated by native rhizobia and yielded significantly less growth than those receiving inoculation. In contrast, the yield of inoculated plants in Ottawa soil did not significantly differ from those without inoculation due to effective nodulation by native R. meliloti. The data indicated synergistic effects on yield by certain paired strain inocula relative to the same strains inoculated individually in Lanark but not in Ottawa soil or Leonard jars.     

Preliminary Studies on Cytoplasmic Inheritance and Variation of Azolla

By investigating the variance of Azolla leaf colour of F1 generation obtained from negative and positive crossing of Azolla between two species (Azolla filiculoides × A. microphylla, A. filiculoides × A. mescicana) and two subgenus (A. filiculoides × A. imbricata), it was revealed that the albinism of the hybrid F1 generation was variation resulting from maternal cytoplasmic inheritance, when A. filiculoide was used as female parent. Electron microscopic observation demonstrated abnormal development of plastid in the albino sporeling. The cell of light green seedling contained both normal and abnormal plastid. Both were probably related to variation in the plastid genotype. Significant difference occurred in the degree and freguency of albinism from various crossing forms, and such change had its vegularity in accord with the variation of the nuclear genotype. The results speculated that albinism were also closely related to the nuclear genotype.     

木霉菌对芸芥生长相关生理指标的影响

芸芥(Eruca sativa)是当今我国蔬菜市场中一种颇具开发价值的新特芳香蔬菜。为了研制促进芸芥生长和提高品质的生防木霉菌剂,本研究以芸芥为试材,在大田条件下,采用本实验室分离鉴定的哈茨木霉T8进行浸种和浇根处理,分析木霉菌对一个生长季内连续栽培三茬30 d龄芸芥的生长相关生理指标的影响。结果表明,施用木霉菌能显著提高芸芥的生物量,改善其光合特性,增强其防御酶活性和脯氨酸含量,提高其产量和营养价值。     

芝麻菜花蜜腺的结构和发育研究

通过解剖镜观察、石蜡切片和薄切片等方法,对芝麻菜的花蜜腺的位置、形态、结构、发育过程及泌蜜前后组织化学变化进行了研究。芝麻菜花蜜腺4枚,分成两对,其中一对侧蜜腺较大,棱柱状,分别着生在外轮2个短雄蕊基部内侧的花托上,结构上由表皮、产蜜组织和维管组织构成;另一对中蜜腺较小,近棒状,分别着生在内轮4个长雄蕊外侧的花托上,结构上仅由表皮和产蜜组织构成。二者表皮细胞外都具角质层,且蜜腺产蜜组织细胞中只含少量的多糖物质。两类蜜腺的蜜汁均由变态气孔泌出体外。无论侧蜜腺还是中蜜腺,蜜腺原基皆是在雌、雄蕊已分化后,由花托相应位置表皮下的1～2层细胞分裂形成的。在蜜腺发育中,产蜜组织细胞在泌蜜前后不具明显的液泡变化。     

Variation in Photosynthetic Rates and Biomass Productivity among Four Mulberry Cultivars

Among four mulberry (Morus alba L.) cultivars (K-2, MR-2, BC2-59, and S-13), highest net photosynthetic rate (P _N) was observed in BC2-59 while the lowest rates were recorded with K-2. Significant differences among the four cultivars were found in leaf area, biomass production, activities of ribulose-1,5-bisphosphate carboxylase and sucrose phosphate synthase, and glucose and sucrose contents. The P _N and the activities of photosynthetic enzymes in the four cultivars were significantly correlated with the growth and biomass production measured as leaf yield, total shoot mass, and aerial plant biomass.