二倍体矮牵牛花粉母细胞异常减数分裂的观察与核型分析  

Observations of Abnormal Meiosis and Karyotype Analysis for Pollen Mother Cells in Diploid Petunia hybrida Vilm.

作　　者：魏跃[1,2] 蔡善亚[1] 董慧[1] 史红林[1] 嵇怡[1] 

机构地区：[1]江苏农林职业技术学院,江苏镇江212400 [2]南京农业大学园艺学院,南京210095

出　　处：《西北植物学报》2016年第12期2440-2447,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：江苏省科技厅自然科学基金(BK20131243);江苏省农业科技自主创新资金(CX(15)1021);江苏农林职业技术学院科研项目(2013kj003)

摘　　要：以夏季高温时期二倍体矮牵牛花蕾为材料,采用常规制片法,对花粉母细胞异常减数分裂进行观察并选取终变期进行染色体核型分析。结果发现:异常减数分裂主要表现为具有多核仁、二价体提前分离成单价体、赤道板外的染色体,姊妹染色单体提前分离、不均等分离,落后和丢失染色体,具有微核的三分体和四分体,中期Ⅱ纺锤体定位发生异常出现融合纺锤体和八字形纺锤体可导致2n花粉产生;矮牵牛终变期核型公式为K(2n)=2x=14=10m+4sm(2SAT),其中第1、4、5、6、7号为中部着丝粒染色体,第2号(具有随体)、3号为亚中部着丝粒染色体,染色体相对长度组成为2n=14=4M_1+10M_2,核型分类为2A型。研究表明,矮牵牛异常减数分裂可导致2n花粉和不育花粉的产生,利用终变期进行核型分析具有材料丰富、二价体形态清晰不需人为配对分析等优点,为矮牵牛细胞学研究提供了新方法。In order to illuminate cytological mechanism of small amount 2npollen existing in petunia,high sterile rate of petunia pollen in hot summer and explore chromosomal karyotype analysis in meiosis period,we conducted the observation of abnormal meiosis and karyotype analysis in meiosis diakinesis period by conventional plate method using flower buds of diploid petunia plant in hot summer as material.The results showed that abnormal meiosis was mainly characterized by multinucleolus,bivalent and sister chromatids dividing beforehand,chromosomes outside metaphase plate,unequal segregation,lagged chromosomes,lost chromosomes,triad and tetrad with micronucleus.These abnormal meiosis behaviour could cause the production of abortive pollen.In metaphaseⅡ,fusing spindles,tripolar spindle in which spindle were orientated abnormally could easily lead to 2npollen formation,the occurrence of 2npollen percentage was 1.51%through statistics.The karyotype formula of Petunia hybrida Vilm.in meiosis diakinesie was K（2n）=2x=14=10m＋4sm（SAT）,which had 5pairs of metacentric chromosomes（chrom.No.1,4,5,6,7）,2pairs of submetacentric chromosomes（chrom.No.2and 3,No.2with satellite）.Relative length was2n=14=4M1＋10M2,belonging to 2Atype.The abnormal meiosis of P.hybridacould lead to the production of 2npollen and sterile pollen,the advantages of karyotype analysis in diakinesis for petunia included abundant materials,clear bivalents form and without artificial pairing analysis,etc al.It provided a new method for study on petunia cytology.

关 键 词：矮牵牛 花粉母细胞 减数分裂 2N花粉 核型分析 

分 类 号：Q253[生物学—细胞生物学] Q343.24