海芋细胞遗传学及花粉发育的研究

Observations on the Behavior of Cytogenetics and Pollen Development of Alocasia odora (Lindl.) K.Koch

采用常规压片法和去壁低渗Giemsa法，研究了海芋Alocasia odora（Lindl．）K．Koch同一居群5株不同个体的细胞遗传学行为和花粉发育过程。结果表明：（1）海芋的体细胞染色体核型为2n=28=20m＋8sm，染色体长度变化在7．84～12．08μm，核型不对称类型为2A；（2）5个不同植株减数分裂中期Ⅰ构型在同一个体中是相对稳定的，在不同个体间存在差异，各株平均构型分别为①5．61Ⅱ°＋3．72Ⅱ＋0．89Ⅳ°＋0．06Ⅴ＋0．78Ⅵ°＋0．06Ⅻ；②10．38Ⅱ°＋3．63Ⅱ；③9．15Ⅱ°＋2．85Ⅱ＋1Ⅳ°；④7．76Ⅱ°＋3．76Ⅱ＋1．24Ⅳ°；⑤8．52Ⅱ°＋3．41Ⅱ＋1．03Ⅳ°。有4个株型具有多价体配对，可形成4条、5条、6条、以及12条染色体连成的环状或链状结构，推测存在染色体相互易位等异常现象，为易位杂合体。（3）减数分裂过程中后期Ⅰ存在染色单体桥和落后染色体，占观察细胞的15．5％；（4）成熟花粉球形，有刺状纹饰，为二细胞型花粉，醋酸洋红压片统计成熟花粉的育性，其败育率为9．3％。

Karyotype, meiotic behavior and pollen development of Alocasia odoras （Lindl.）K. Koch were investigated. The results showed that. （ 1 ） The karyotype formula of somatic cell was 2n = 28 = 20 m ＋ 8 sm, belonging to Stebbins＇ s 2A type. The chromosome length was in the range of 7.84 - 12. 08 μm, and the ratios of the long ann to short arms were between of 1.02 - 2. 72. （2） At meiotic metaphase I of pollen mother cells（ PMCs）, some of the non-homologous chromosomes underwent reciprocal transloeation as indicated by ring or chain structures, formed by four, five, six and sometimes up to twelve chromosomes. Quadruples occurred more frequently than other configurations. These demonstrated that the plants of the species were translocation heterozygotes. Mean configurations calculated through five individuals of one population were 5.61Ⅱ°＋3.72Ⅱ＋0.89Ⅳ°＋0.06Ⅴ＋0.78Ⅵ°＋0.06Ⅻ,10.38Ⅱ°＋3.63Ⅱ;9.15Ⅱ°＋2.85Ⅱ＋1Ⅳ°,7.76Ⅱ°＋3.76Ⅱ＋1.24Ⅳ°,8.52Ⅱ°＋3.41Ⅱ＋1.03Ⅳ°, respectively, where Ⅱ°, Ⅳ° and Ⅵ° symbolize the rings of bivalent, quadruple and hexadruple. The metaphase Ⅰ configuration was constant for individual plant but variable among different individuals. （3）Chromosomal bridges and lagging at anaphase Ⅰ were at a ratio of 15.5% of the observed cells. （4）The mature pollen was spherical and binucleate, and having spinose exine. The ratio of sterile pollen was 9.3%.