生物技术在花卉植物遗传育种上的应用

生物技术的发展为花卉植物种质资源的研究、创新及新品种培育提供了更多的途径。该文对花卉植 物的离体保存、分子标记及细胞工程、基因工程在花卉植物种质创新方面的研究进展及取得的成果进行了综 述,并对存在的问题及今后的发展方向进行了探讨,以期为相关研究提供参考。     

基因甘蔗：潜能、现状和前景

从基因中在甘蔗上的应用潜能、甘蔗遗传转化的方法及其成效、启动子及选择标记对基因表达和转化体筛选的效应,基因工程甘蔗的成就等几个方面进行综述评述,并提出了进一步的研究方向。     

基因工程甘蔗：潜能、现状和前景

从基因工程在甘蔗上的应用潜能、甘蔗遗传转化的方法及其成效、启动子及选择标记对基因表达和转化体筛选的效应、基因工程甘蔗的成就等几个方面进行综合评述,并提出了进一步的研究方向。     

基因工程创造神奇花卉

世界花卉贸易年年增长,竞争也越来越激烈,当前除了依靠高效栽培管理系统外,非常重要的就是花卉品种的改良。由于花卉本身遗传背景复杂,自然界种质资源又有限,传统的杂交育种已难以满足花卉育种要求。 生物技术使花卉园艺业产生了巨大变化组织培养现已成为花卉快繁脱毒不可缺少的重要手段。1977年,世界上首家基因工程公司在美国诞生,标志着基因工程即将进入实用阶段,此后生物技术公司如雨后春笋,可以这么说,基因工程成了本世纪生命科学最突出的成就。由于基因的鉴定、分离、及其转化技术的极大发展,特别是近年发展起来的反义RNA技术,可     

基因工程在水稻改良方面的研究进展

近十年来,植物基因工程取得了辉煌的成就,尤其是许多大田作物（如棉花、玉米、烟草、马铃薯、蕃茄等）的转基因产品已进入商品化生产阶段。本文就基因工程在水稻改良方面的研究作一简要综述,主要包括抗病虫性改良、抗逆性改良和品质性状改良等方面     

花卉育种技术研究进展(综述)

本文综述近年来国内外花卉育种技术及成果。常规育种仍是花卉育种的主要方法,但日益成熟的生物技术为花卉育种提供了新的途径,尤其是基因工程在改良花卉的色、香、形及延缓衰老等方面将发挥重要作用。     

花卉基因工程研究进展Ⅰ：花色

1987年人们首次通过转基因技术获得了改变花色的矮牵牛,使得花卉选育迈入分子时代。其优点在于可有目的的地改变花卉的某一性状而不影响其它性状,并缩短育种周期。目前,与花色基因工程有关调控机理已日益清楚,分离到大量的相关酶和基因,获得了一批转基因花卉。本文重点介绍了国内外花色基因工程的研究进展,同时简单评述了花卉基因工程研究中存在的问题并展望其应用前景。     

花卉花色基因工程的研究现状及存在问题

与传统的花卉育种手段相比 ,基因工程育种具有周期短、目的性强等优点 ,因而成为近年来花卉育种的重要手段之一。花色是花卉育种的一个重要性状 ,自1987年首次通过基因工程方法获得了改变花色的转基因矮牵牛以来 ,花卉花色育种进入了分子时代。简要介绍了近年来国内外花卉花色基因工程及花器官特异表达启动子的研究进展及应用前景。     

观赏植物花色基因工程研究进展

花色是观赏植物的重要性状,创造新花色是花卉育种的主要目标之一。基因工程技术 在观赏植物花色育种上可弥补传统育种技术的缺陷,因此它在花色育种方面的研究和应用发 展迅速。本文从花的成色作用和花色素种类入手,介绍了花色苷的生物合成,并从花色基因 的种类和克隆、花色基因工程操作的策略和方法等角度综述了近年来观赏植物花色基因工程 的研究进展。同时对我国观赏植物花色基因工程的前景作一展望。     

观赏植物花色基因工程研究进展

花色是观赏植物的重要性状,创造新花色是花卉育种的主要目标之一。基因工程技术在观赏植物花色育种上可弥补传统育种技术的缺陷,因此它在花色育种方面的研究和应用发展迅速。本文从花的成色作用和花色素种类人手,介绍了花色苷的生物合成,并从花色基因的种类和克隆、花色基因工程操作的策略和方法等角度综述了近年来观赏植物花色基因工程的研究进展。同时对我国观赏植物花色基因工程的前景作一展望。     

基于花青素代谢培育蓝色花卉的研究进展

花色是植物吸引昆虫传播花粉的主要因素,对于植物在自然界的生存必不可少,也是观赏植物最重要的性状之一。在蓬勃发展的花卉产业中,色彩各异花卉的培育,可以弥补自然花色的匮乏,但是令人垂涎的蓝色花比较难培育。花色的多样性主要是由花青素及其衍生物的种类和含量等因素决定的,飞燕草色素的合成是形成蓝色花的关键因素,许多植物体内缺少合成飞燕草色素的结构基因。近年来,利用基因工程技术培育蓝色花的研究也时有报道。文中以常见的观赏植物为例,基于花青素代谢调控,从影响飞燕草色素合成的关键因素和不同分子改良途径培育蓝色花等几个方面对植物花朵呈色的机制进行了综述,并展示不同分子育种策略可能在其他领域的应用,为其他植物或经济作物的色泽改良如彩色棉蓝色纤维的培育等提供参考和技术支持。     

Genetic and linkage analysis of purple-blue flower in soybean

Flower color of soybean is primarily controlled by genes W1, W3, W4, Wm, and Wp. In addition, the soybean gene symbol W2, w2 produces purple-blue flower in combination with W1. This study was conducted to determine the genetic control of purple-blue flower of cultivar (cv). Nezumisaya. F(1) plants derived from a cross between Nezumisaya and purple flower cv. Harosoy had purple flowers. Segregation of the F(2) plants fitted a ratio of 3 purple:1 purple-blue. F(3) lines derived from F(2) plants with purple-blue flowers were fixed for purple-blue flowers, whereas those from F(2) plants with purple flowers fitted a ratio of 1 fixed for purple flower:2 segregating for flower color. These results indicated that the flower color of Nezumisaya is controlled by a single gene whose recessive allele is responsible for purple-blue flower. Complementation analysis revealed that flower color of Nezumisaya is controlled by W2. Linkage mapping revealed that W2 is located in molecular linkage group B2. Sap obtained from banner petals of cvs. with purple flower had a pH value of 5.73-5.77, whereas that of cvs. with purple-blue flower had a value of 6.07-6.10. Our results suggested that W2 is responsible for vacuolar acidification of flower petals.     

Flower Color Modification by Engineering of the Flavonoid Biosynthetic Pathway: Practical Perspectives

The status quo of flavonoid biosynthesis as it relates to flower color is reviewed together with a success in modifying flower color by genetic engineering. Flavonoids and their colored class compounds, anthocyanins, are major contributors to flower color. Many plant species synthesize limited kinds of flavonoids, and thus exhibit a limited range of flower color. Since genes regulating flavonoid biosynthesis are available, it is possible to alter flower color by overexpressing heterologous genes and/or down regulating endogenous genes. Transgenic carnations and a transgenic rose that accumulate delphinidin as a result of expressing a flavonoid 3′,5′-hydroxylase gene and have novel blue hued flowers have been commercialized. Transgenic Nierembergia accumulating pelargonidin, with novel pink flowers, has also been developed. Although it is possible to generate white, yellow, and pink-flowered torenia plants from blue cultivars by genetic engineering, field trial observations indicate difficulty in obtaining stable phenotypes.     

Genetic engineering of flavonoid pigments to modify flower color in floricultural plants

Recent advances in genetic transformation techniques enable the production of desirable and novel flower colors in some important floricultural plants. Genetic engineering of novel flower colors is now a practical technology as typified by commercialization of a transgenic blue rose and blue carnation. Many researchers exploit knowledge of flavonoid biosynthesis effectively to obtain unique flower colors. So far, the main pigments targeted for flower color modification are anthocyanins that contribute to a variety of colors such as red, pink and blue, but recent studies have also utilized colorless or faint-colored compounds. For example, chalcones and aurones have been successfully engineered to produce yellow flowers, and flavones and flavonols used to change flower color hues. In this review, we summarize examples of successful flower color modification in floricultural plants focusing on recent advances in techniques.     

The codA transgene for glycinebetaine synthesis increases the size of flowers and fruits in tomato

The tolerance of various species of plant to abiotic stress has been enhanced by genetic engineering with certain genes. However, the use of such transgenes is often associated with negative effects on growth and productivity under non-stress conditions. The codA gene from Arthrobacter globiformis is of particular interest with respect to the engineering of desirable productive traits in crop plants. The expression of this gene in tomato plants resulted in significantly enlarged flowers and fruits under non-stress conditions. The enlargement of flowers and fruits was associated with high levels of glycinebetaine that accumulated in reproductive organs, such as flower buds and fruits. The enlargement of flowers was related to an increase in the size and number of cells, and reflected the pleiotropic effect of the codA transgene on the expression of genes involved in the regulation of cell division.     

Anther-smut infection of Silene alba caused by Ustilago violacea: factors determining fungal reproduction

Summary The anther-smut fungus Ustilago violacea sporulates in flowers of the dioecious host plant Silene alba. Growth chamber comparisons of healthy and diseased plants, with the genetic background of host and pathogen controlled, revealed that fungal infection increases the number of flowers produced per plant and decreases the size of individual flowers. There were few consistent effects of plant genotype or fungal isolate on diseased flower traits, but differences between the plant sexes were apparent. Stimulation of flower production is proportionally greater in females than males: thus, although healthy male plants produce many more flowers than healthy females, sexual differences in diseased flower number are reduced. Sexual differences in diseased flower size also exist, with male flowers smaller than females. A field inoculation study confirmed dimorphism in diseased flower size and demonstrated that spore production per flower was greater for males than females for all flower size classes.     

Role of sink–source relationships in chrysanthemum flower size and total biomass production

The present work was aimed at understanding and quantifying the effect of sink–source relationships on flower size, using chrysanthemum as a model system. Sink/source ratio was manipulated by flower bud removal (leaving one, two or four flowers, and a control), axillary shoot removal, and varying daily light integral. Furthermore, the influence of flower position within the stem on the flower size was investigated. All means applied to reduce sink/source ratio resulted in a significantly higher individual flower dry mass and area in plants with a fixed number of flowers. Nevertheless, control plants responded to supplementary assimilation light with an increased number of flowers rather than producing larger flowers. Flower position had a negligible effect on flower size in both disbudded and control plants, except that the second-order lateral flowers were significantly smaller than the first-order ones. Singly flowered plants without side shoots represented the greatest potential flower size; they had flowers up to 2.4 times heavier than the control plants. Total aerial plant dry mass was only reduced at very low sink strength treatments, whereas flower mass ratio showed a saturating response to the number of flowers per plant. The results indicate that individual flower size is very sensitive to total plant sink strength, but it does not change with plant source strength when the number of flowers is not manipulated.     

花色改造基因工程

自1987年世界首例成功运用转基因技术改造矮牵牛花色以来,花色改造基因工程技术不断展现它在培育新花色品系上的无穷魅力。介绍了近年来运用基因工程技术成功改造花色的3种主要策略:(1)采用反义RNA及共抑制的方法来改变花颜色的深浅;(2)通过导入新基因产生新奇花色;(3)利用转座子构建特殊表达载体,随机激活花色合成的基因来产生嵌合花色。此外,还对转基因株花色不稳定原因进行了讨论。