栽培小菊17个品种的核型多样性  

Karyotype Diversity of 17 Chrysanthemum Cultivars with Small Inflores-ceuces

作　　者：李畅[1] 陈发棣[1] 赵宏波[1] 陈素梅[1] 

机构地区：[1]南京农业大学园艺学院,南京210095

出　　处：《园艺学报》2008年第1期71-80,共10页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(30400308)

摘　　要：采用常规压片法对具有不同株型和用途的17个栽培小菊品种制备染色体标本,进行核型分析。结果表明:(1)17个栽培小菊均为混倍体,染色体数在49～57之间变异,以54条为主;(2)染色体呈现多态性:多数品种由中部、近中部和近端部着丝粒染色体组成;最长与最短染色体的比值为1.62～2.39;臂比>2的染色体所占的比率为11.11%～29.62%;核型不对称系数为59.74%～63.37%;3个地被菊品种和‘奥运橙光’、‘金陵白凤’(2n=53)核型类型为"2B",其它品种为"2A"型。核型多样性不仅仅是简单的染色体突变,很可能是染色体重组所致。Karyotype was studied via squash method in seventeen chrysanthemum cuhivars with small inflorescences which differ in plant architecture and purpose. Karyotypic findings showed that all cuhivars were mixoploid with chromosome number ranging from 49 to 57, and 54 was the most frequent number observed. In addition, diversity of chromosome morphology was observed. Metacentric, submetacentric and acrocentric chromosomes coexisted in most cuhivars. The ratio of chromosome length, i. e. , ratio of the length of the longest chromosome to that of the shortest one, varied from 1.62 to 2.39. The percentage of chromosome with ann ratio beyond 2 was between 11.11% and 29.62%. Asymmetry index （ As. K% ） ranged from 59.74% to 63.37%. The karyotypes of Dendranthema ×grandiflorum ‘ Aoyunchengguang＇,‘Jinlingbaifeng＇ （2n =53） and three ground cover cuhivars were characterized as ＂2B＂ type, whereas, those of the remaining cuhivars were characterized as ＂2A＂ type. Karyotype diversity not solely resulted from the mutation of chromosome, recombination of chromosome also likely contributed to the diversity.

关 键 词：菊花 小菊 染色体数 核型 多样性 

分 类 号：S682.21[农业科学—观赏园艺]