不同籽粒颜色藜麦品种的核型分析

Karyotype Analysis of C.quinoa Varieties with Different Seed Color

为了明确青海省主推藜麦品种的染色体数目和核型特征,以柴达木黑-1(简称黑藜麦)、柴达木白-1(简称白藜麦)及柴达木红-1(简称红藜麦)3种不同籽粒颜色的藜麦品种为材料,对其根尖采用普通压片法进行制片,经冰水混合物预处理、卡诺固定液固定、45%醋酸酸解、火焰干燥压片、镜检、DAPI染色、荧光显微镜拍照等步骤进行核型分析。结果表明:3种颜色的供试品种染色体数均为4n=36条,未发现非整倍体或多倍体现象。黑藜麦的核型公式为4n=36=32m(4AST)+4sm,染色体相对长度组成为4n=36=2L+18M2+12M1+4S;白藜麦的核型公式为4n=36=34m(4SAT)+2sm,染色体相对长度组成为4n=36=2L+20M2+14M1;红藜麦的核型公式为2n=36=34m(4SAT)+2sm,染色体相对长度组成为4n=36=6L+8M2+14M1+8S。3个品种的核型不对称系数分别是58.20%,58.22%,58.72%,核型均为2B类型,表明这些品种较为进化。3个品种均具有2对随体,但位置存在差异,可能与藜麦异源起源、自花授粉等因素有关。该研究可为藜麦杂交育种、倍性育种、种质资源鉴定和基因定位等研究提供细胞学基础。

In order to determine the chromosome number and karyotype characteristics of the main Chenopodium varieties in Qinghai Province,three quinoa varieties with different seed colors Qaidam black-1(abbreviated as black quinoa),Qaidam white-1(abbreviated as white quinoa)and Qaidam red-1(abbreviated as red quinoa)were used as materials,and their root tips were sliced by using squashing method.Karyotype analysis was carried out through the steps of ice-water mixture pretreatment,Carnot fixed solution,45%acetic acid hydrolysis,flame drying and pressing,microscopic examination,DAPI staining,fluorescence microscope photography etc.The results showed that:The chromosome numbers of the three color varieties were all 4n=36,and no aneuploid or polyploid phenomenon was found.The karyotype formula and the relative length composition of chromosome of black quinoa were 4n=36=32m(4AST)+4sm,4n=36=2L+18M2+12M1+4S;the karyotype formula and the relative length of chromosome of white quinoa were 4n=36=34m(4SAT)+2sm,4n=36=2L+20M2+14M1;the karyotype formula and the relative length of chromosome of red quinoa were 4n=36=34m(4SAT)+2sm,4n=36=6L+8M2+14M1+8S.All varieties belong to 2B type and the asymmetry index were 58.20%,58.22%and 58.72%,respectively,indicating that these varieties were more evolved.All the three varieties have two pairs of satellite,but there were differences in loction,which may be related to the heterologous origin of quinoa,self-pollination and other factors.This study can provide cytological basis for cross breeding,ploidy breeding,germplasm resource identification and gene mapping of C.quinoa.