染色体G带分析与自动识别

通过对染色体Ｇ带特征进行定性，定量分析，仿照人工识别过程，利用统计识别，相关匹配，模糊聚类等方法，使自动识别率达９５％以上，略加人工校正，即可投入现场使用。     

小麦与高冰草不对称体细胞杂种F5代部分株系的花粉母细胞染色体观察分析

普通小麦（Triticum aestivum L.)济南177原生质体（受体）和经紫外线照射的高冰草（Agropyron elongatum)原生质体（供体）用PEG法诱导融合，形成外形偏向小麦的不对称体细胞杂种及后代，经过田间繁育，现已到F5代，在对F1至F4代杂种植株完成各项分析的基础上，对对F5代不同株系（Ⅱ-2，8-1，Ⅱ-Ⅰ-8）的花粉母细胞染色体进行观察和分析，结果表明，杂种花粉母细胞在减数分裂时基本正常，88％以上的细胞染色体数目在20－21对之间，并且绝大多数染色体可以正常配对形成二价体，少数细胞存在小染色体，数目多为1－2个，且大部分以配对形式存在，由此可见，杂种在遗传上基本是稳定的，且杂种的表型及遗传在较短的世代就基本稳定，但个别杂种花粉母细胞中也存在减数分裂异常现象，如不均等分离，落后染色体，染色体桥、多着丝粒体，易位环及多价体等。     

啤酒大麦染色体GiemsaC带核型比较分析

采用改良Ｃ带法对啤酒大麦７个品系染色体的Ｇｉｅｍｓａ Ｃ带核型进行了比较分析，结果表明，不同大麦品系间相同序号染色体的Ｇｉｅｍｓａ Ｃ带分布相似，带的数目和强弱存在明显差异，不同染色表现不同程度的Ｃ带带型多样性，第１，３，４染色体的带型具有较大的多样性，而各品系间第６染色体地带型相同。     

A simple method for the preparation of hydra chromosome spreads: introducing chromosome counts into hydra taxonomy

Summary A simple method to prepare chromosome spreads of hydra is described. Chromosome counts for a non-symbiotic brown hydra,Hydra vulgaris attenuata, and the Swiss strain of a symbiotic green hydra indicated a diploid number of about 2n=30 in each case. It is suggested that chromosome number may be used to define hydra species more precisely.This work was done while A. R. and M. R. were on leave in Oxford. We thank Prof. D. C. Smith F. R. S. for providing laboratory facilities. We wish to thank Prof. Smith and Dr A. E. Douglas for reading earlier drafts of this paper.     

苦荞麦染色体的加倍研究

应用秋水仙素和二甲基亚砜混合液对中国西南地区的三种苦荞麦品种进行染色体加倍,获得了同源四倍苦荞新品系.与原种相比,同源四倍苦荞新品系具有发达的根系、较大的籽粒和高大植株,其产量得到明显提高.新品系的蛋白质、氨基酸、维生素经及其他药用成分的含量也有明显的提高.此外,新品系有较高的接实率,能稳定遗传,具有较强的抗逆能力.     

大果蝇（Drosophilagrandis）的形态观察和染色体研究

本文介绍了一种野生大果蝇的形态特征和染色体方面的研究结果。形态观察表明，这种野生大果蝇有许多形态特征不同于D.melanogaster，如个体较大，性柱位置不同等。染色体研究发现，此种果蝇的唾液腺染色体比D.melanogaster大得多，具有6条长臂和1条短臂，；核型为2n=12,4R 1V 1D。     

车前属两个种的核型报道

报道了车前属两种车前的核型。Ｐｌａｎｔｏｇｏ ｌｅｓｓｉｎｇｉｉ Ｆｉｓｃｈ．ｅｔ Ｍｅｙ为２ｎ＝１２，核型属于“２Ａ”，核型公式为Ｋ（２ｎ）＝１２＝１０ｍ＋２ｓｍ；Ｐ．ｍｉｎｕｔａ Ｐａｌｌ为２ｎ＝１２，核型仍属“２Ａ”型，核型公式Ｋ（２ｎ）＝１２＝８ｍ＋２ｓｍ＋２ｓｔ。染色体相对长度组成２ｎ＝２Ｌ＋４Ｍ２＋４Ｍ１＋２Ｓ１，２ｎ＝６Ｍ２＋６Ｍ１，染色体总长分别为３０．６０，２９．８０，由１２对染     

人工染色体研究进展

细菌人工染色体（ＢＡＣｓ）、噬菌体Ｐ１衍生的人工染色体（ＢＡＣｓ）和酵母人工染色体（ＹＡＣｓ）是近年发展起来的ＤＮＡ克隆新技术。着重介绍了ＹＡＣｓ作为转移大分子外源ＤＮＡ的载体，在生物基因组分析，基因的结构与功能、表达与调控、定位与分离以及遗传病的基固治疗等研究领域的应用。比较了ＢＡＣｓ、ＰＡＣｓ和ＹＡＣｓ的主要特点。对哺乳动物人工染色体的研究情况也作了简要介绍。     

大瓶螺（Ampullar ia gigas Spix）的核型分析

本文采用鳃及性腺组织制片法，分析大瓶螺染色体组型，结果表明，大瓶螺染色体为２ｎ＝２８，可配为１４对，除３、８、１２这３对为亚中部着丝点染色体外，其余皆为中部着丝点染色体，染色体长度呈连续递变，其中相对长度最长的１号染色体为１０．０９，最短的１４号染色体为５．１０，ＮＦ＝５６，全套染色体上未发现有次缢痕，随体及与性别有关的性染色体存在。     

Testes and chromosomes in interspecific hybrids betweenHelicoverpa armigera (Hübner) andHelicoverpa assulta (Guenée)

The interspecific hybridization betweenHelicoverpa armigera females andHelicoverpa assulta males yieldedF ₁ hybrids (RS), fertile males and sterile individuals with abnormal genitals. The reverse hybridization betweenH. assulta females andH. armigera males yielded F₁ hybrids (SR)-fertile males and fertile females. The morphology of testes and the karyotype of chromosomes of larvae in the hybrids were investigated. Among the 2d old fifth-instar SR larvae, individuals without testes were fertile females and those with testes were fertile males. The length and breadth of testes between SR and parental species were not significantly different (p>0.05). Among the 2d old fifth-instar RS larvae, the testes were observed in all the individuals, but it could be classified into two types. The length and the breadth of testes in Type 1 larvae were not significantly different from those of their parental species (p>0.05), while those in Type 2 were significantly less than those of their parental species (p<0.01). Mitotic metaphase I of brain cells showed the diploid chromosomes number of both reciprocal hybrids was 2n=62, as many as their parents. The haploid number of 31 was confirmed by counts from spermatocytes at meiotic metaphase from SR male larvae and Type 1 larvae of RS. Meiosis was not observed in spermatocytes of Type 2 larvae of RS. Considering the characteristics of adult hybrids of RS, it was concluded that Type 1 individuals in RS were fertile and those of Type 2 were sterile. The sterility of Type 2 individuals in RS is attributed to the abnormity in development of testes and the failing meiosis of spermatocytes. As a result, the normal spermatozoon could not been produced.