贯叶连翘的离体培养与四倍体诱导

以贯叶连翘种子发芽后的无菌苗为外植体,进行了贯叶连翘的组织培养与四倍体诱导研究。结果表明,贯叶连翘的子叶和下胚轴具有较高的愈伤组织诱导率,在2,4-D 1.0 mg/L或NAA 0.5 mg/L配合6-BA0.5 mg/L使用,并添加500 mg/L CH时能提高愈伤组织诱导率,并提高愈伤的质量;分化培养基中添加6-BA0.5~1.0 mg/L和NAA0.05~0.1 mg/L的效果最好;培养基中添加0.5 mg/L 6-BA与500~800 mg/L CH能使丛生苗快速增殖,并生长粗壮,叶色浓绿;采用0.3%秋水仙碱溶液浸泡茎尖24 h,效果最佳,存活率28%,四倍体诱导率为6%。     

重瓣铁线莲愈伤组织诱导研究

[目的]为运用现代生物技术开发利用重瓣铁线莲提供参考。[方法]以重瓣铁线莲的茎段为外植体,在MS基本培养基中添加0.2mg/L IAA,0.5、1.0、1.52、.0 mg/L的6-BA和0.1、0.2、0.4、0.6、0.81、.0 mg/L的2,4-D,观察重瓣铁线莲愈伤组织的诱导情况,统计诱导率。[结果]各处理诱导出的愈伤组织均为致密型愈伤组织,很少进行分裂分化,故在增殖培养中需提高植物生长物质的浓度。培养基MS+1.0 mg/L 6-BA+0.8 mg/L 2,4-D+0.2 mg/L IAA的诱导效果最好,不仅形成的愈伤组织量多,而且诱导率高达90.0%。在重瓣铁线莲愈伤组织诱导中,植物生长物质6-BA、2,4-DI、AA的适宜比例为5∶4∶1。[结论]重瓣铁线莲茎段愈伤组织适宜的诱导培养基为:MS+1.0mg/L 6-BA+0.8 mg/L 2,4-D+0.2 mg/L IAA。     

胚胎干细胞体外培养研究进展及设想

胚胎干细胞具有高度复制能力及多向性分化潜能,近年来由于胚胎干细胞的分离、培养技术的提高,尤其是对干细胞表面分子标记和诱导分化研究的深入,胚胎干细胞展示出很好的临床应用前景,同时也将为基因功能研究、药物研究提供良好的工具。但对基因组印迹、免疫排斥及干细胞的有效定向分化仍然是亟待解决的问题。     

运用致病毒素筛选抗烟草黑胫病细胞突变体 Ⅱ 抗毒素愈伤组织的再生植株及其后代的抗病性鉴定

 用黑胫病粗毒素作为选择压力,结合辐射诱变技术,从烟草花粉植株叶片的愈伤组织中筛选出抗毒素的愈伤组织,并对其再生植株及其M₂代进行抗病性鉴定、选育。目前已获得6个高抗黑胫病的细胞突变株系,且抗病性状表现稳定,并建立了一套烤烟抗黑胫病突变体的筛选和鉴定体系。研究结果表明,在细胞水平上筛选抗病突变体是开发新抗源的有效途径。     

Allozyme Variation Among Some Pearl Millet (<Emphasis Type="Italic">Pennisetum glaucum</Emphasis> L.) Cultivars Collected from Tunisia and West Africa

Allozyme variation was assessed in a collection of pearl millet cultivars derived from three different regions of traditional cultivation of this cereal in Tunisia and West African countries. Using starch gel electrophoresis, 11 loci corresponding to seven enzyme staining systems were identified. Important within-cultivar genetic diversity was detected. Genetic diversity within Tunisian cultivars was similar and was more pronounced than for West African ones. This result could be explained by the low level of the human selection characterizing the Tunisian cultivars. Most of the total genetic diversity is maintained within subregions suggesting little genetic differentiation. Cluster analysis did not reveal separate clusters for the various subregion cultivars. However the cluster analysis should help in the selection of interesting genotypes for future breeding programs.     

Phylogenetic differentiation of cultivated rice,XXIII. Potentiality of wild progenitors to evolve the Indica and Japonica types of rice cultivars

Summary Studies of intermediate wild-cultivated plants suggested that the Indica-Japonica differentiation of cultivars of Oryza sativa L. has taken place with the domestication of wild plants. The wild progenitor, which is considered to be the Asian form of O. perennis Moench, shows no trace of differentiation into two such types as the Indica and Japonica. To elucidate the potentiality of the wild progenitor to evolve the two types when domesticated, the selfed progenies from an Indica × wild and a japonica × wild cross were examined with regard to three characters known to be useful for distinguishing between the two types. The data showed that Japonica-like plants were derived from the Indica × wild cross and Indica-like plants from the Japonica × wild cross. The Indica-Japonica differentiation was considered to have resulted from selection of incipient domesticates having such potentiality under different climatic conditions; the dynamics was discussed.     

云南水稻品种的亲和性分析

将１０１个云南水稻品种分别与３个籼型和３个粳型测验品种杂交，考察了各组合Ｆ１的小穗育性。同时对各被测品种的６种形态性状的分化按程氏指数法进行调查，分析了云南稻品种亲和性分化与形态性状分化之间的关系。根据测交Ｆ１小穗育性的高低，参照籼粳测验品种之间Ｆ１的育性水平，可将被测品种的亲和性分成灿型、粳型、中间型、广亲和型和特殊亲和性５个类群。各类群所含品种数分别为４７个、２１个、１６个、６个和５个，另有６     

不同种（品种）三叶草愈伤组织诱导及分化影响因素研究

以9个三叶草品种的上胚轴、下胚轴、叶片和子叶为外植体,研究了影响三叶草愈伤组织诱导和再分化的主要因素。结果表明,不同品种不同外植体愈伤诱导率差异较大,下胚轴为较适宜的外植体,其平均愈伤组织诱导率和愈伤分化率为97％和10．3％,改良SH＋2,4-D8．0mg／L＋6-BA0．2mg／L＋KT0．2mg／L为最佳胚性愈伤组织诱导培养基,所形成的愈伤组织的愈伤分化率也最高。     

温湿度条件与凯特杧两性花百分率关系的研究

为探索温湿度条件与杜果两性花百分率的关系，以“凯特杜”为研究对象，以两性花百分率为方程依变量，55个温湿度因子为自变量，应用数理统计方法分析了两者的相关关系。结果表明：“凯特柱”是两性花百分率较高的品种，随花期延后，温度增高，两性花百分率提高；花器官主要分化期自开花前30d开始至花前1d结束；两性花百分率受花器官主要分化期日均高温、日均温、日均低温和日积温的影响，四者的影响规律相似。花前21～30d、11～15d、1～5d的日均高温、日均温、日均低温、日积温以及花前6～１０d的日均温、日均低温、日积温与两性花百分率为直线相关，随温度增高，两性花百分率提高；花前16～20d的日均高温、日均温、日均低温、日积温以及花前6～１０d的日均高温与两性花百分率为多项式线性相关，温度由低升高两性花百分率提高，但超过一定温度则降低。花器官主要分化期全程的日均空气湿度均对两性花百分率有影响，但最敏感时期为花前11～20d。由此认为，“凯特杜”小花子房退化与花器官主要分化期所处的温湿度环境密切相关，适当高的温湿度有利于子房的发育和两性花百分率的提高。     

Diversification of Multipurpose Plant, <Emphasis Type="Italic">Perilla Frutescens</Emphasis>

The traditional Asian crop, Perilla frutescens has multiple uses. There are specialized cultivars for seed oil and for medicinal use, as well as wild/weedy forms growing in various habitats. Based on selective characteristics of leaf odor, anthocyanin pigmentation, seed hardness and seed diameter, the diversity of this species was investigated to clarify the intraspecific differentiation. P. frutescens was divided into five groups by the combination of three qualitative characteristics: leaf odor, anthocyanin pigmentation and seed hardness. Most of the plants cultivated for oil belonged to one group, while medicinal plants belonged to three other groups. Wild/weedy forms were in the last group. The five groups could not be distinguished by seed diameter. Though the plants cultivated for oil tended to have larger seeds than the medicinal and wild/weedy plants, there was no boundary either between the two crops, or among various phenotypes of P. frutescens.