IDENTIFICATION OF LINKAGE GROUPS USING TORISOMIC SERIES IN CITRUS

使用柑橘中的异构序列鉴定连锁群

基本信息

批准号：
05660035
负责人：
WAKANA Akira
金额：
$ 1.41万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

Because of the presence of the problems of long juvenility, nucellar embryogenesis and so on, genetic analysis in Citrus was difficult. Recently, however, linkage relationship of molecular genes has been reported by several workers, as the methods for molecular genetics develops. To use these genes as genetic markers and to develop the chromosome map for Citrus, it is essential to show which chromosome has them. The purpose of the present studies is to produce trisomic series using triploid citrus, and to identify the chromosome containing isozyme genes using trisomic series.Both cross combinations 2X*3X and 3X*2X produced trisomic seedlings with chromosome number of 2n=19. But the frequency of trisomic seedlings obtained was very low. In the case of 2X*3X almost all seedlings obtained were dipliod with 18 chromosomes, and a few aneuploid seedlings were obtained. In the case of 3X*2X relatively a large number of aneuploid seedlings were obtained, but number of trisomic seedlings obtained was small. The undeveloped embryos within the imperfect seeds obtained from both crosses were cultured in vitro, but we failed to produce a alrge number of seedlings from these embryos. Only 10 seedlings obtained through the embryo culture were diploid. We improve the culture now.In the present study, we obtained 18 trisomic seedlings. However, growth rate pf these seedlings were very low and some of them were dead Hence, we could not performed isozyme analysis using these seedlings. The morphology of chromosomes of trisomic seedlings was observed by several methods, but we could not identified the trisomic chromosome. Based on the present study, further research will be cont inued.

由于柑橘存在长幼期、珠心胚胎发生等问题，遗传分析十分困难。然而，最近，随着分子遗传学方法的发展，一些工作者报道了分子基因的连锁关系。为了使用这些基因作为遗传标记并开发柑橘的染色体图谱，必须显示哪条染色体上有这些基因。本研究的目的是利用三倍体柑橘产生三体系列，并利用三体系列鉴定含有同工酶基因的染色体。杂交组合2X*3X和3X*2X均产生染色体数目为2n=19的三体幼苗。但获得三体苗的频率很低。在2X*3X的情况下，获得的幼苗几乎都是18条染色体的二倍体幼苗，并且获得了少量的非整倍体幼苗。在3X*2X的情况下，获得较多的非整倍体幼苗，但获得的三体幼苗数量较少。从两个杂交中获得的不完美种子中未发育的胚胎在体外培养，但我们未能从这些胚胎中产生大量的幼苗。通过胚培养获得的幼苗仅有10株是二倍体。我们现在改进培养物。在本研究中，我们获得了18株三体苗。然而，这些幼苗的生长速度非常低，其中一些幼苗已经死亡，因此，我们无法使用这些幼苗进行同工酶分析。通过多种方法观察了三体幼苗的染色体形态，但未能鉴定出三体染色体。在目前研究的基础上，将继续进行进一步的研究。