大白菜非整倍体组织培养中污染控制研究

[目的]为大白菜珍贵遗传材料的保存提供参考。[方法]以受细菌污染的大白菜非整倍体组培苗和田间植株为材料,以常规消毒处理为对照,分别采用常规消毒＋培养基中添加不同抗生素和农用杀菌荆预处理＋常规消毒对组培苗和外植体（取自田间植株）进行处理,研究不同处理对污染的控制效果。[结果]对照组组培苗培养7、14d时,污染率分别为9．1％和36．4％,培养基申添加100mg／L氨苄青霉素可有效控制污染;常规消毒外植体接种7d后污染率迭58,8％,杀菌剂预处理＋常规消毒可有效控制真菌对外植体的污染,但对细菌无明显作用。[结论]培养基中添加氨苄青霉素、采用合适杀菌剂对外植体进行预处理可有效控制大白菜非整倍体组织培养过程中的污染。     

染色体分带和非整倍体技术在小麦细胞遗传研究中的综合运用

本文讨论了作者在小麦及其亲缘物种的进化、起源和小麦与亲缘种属间染色体或染色体片段的转移研究中,综合运用核型分析(Karyotype analysis)、染色体分带(Chromosome banding)和非整倍体技术(Aneuploid technique),以提高工作效率和增加研究结果准确性的新途径。     

BAC-derived SSR markers chromosome locations in cotton

Bacterial artificial chromosome (BAC) libraries with large DNA fragment inserts have rapidly become the preferred choice for physical mapping. BAC-derived microsatellite or simple sequence repeats (SSRs) markers facilitate the integration of physical maps with genetic maps. The objective of this research was to identify chromosome locations of the BAC-derived SSR markers in tetraploid cotton. A total of 192 SSR primer pairs were derived from BAC clones of an Upland cotton genetic standard line TM-1 (Gossypium hirsutum L.). Metaphor agarose gel electrophoresis results revealed 76 and 59 polymorphic markers between TM-1 and 3–79 (G. barbadense) or G. tomentosum, respectively. Using deletion analysis method, we assigned 39 markers out of the 192 primer pairs to 17 different chromosomes or chromosome arms. Among them, 19 and 17 markers were localized to A-subgenomes (chromosome 1–13) and D-subgenomes (chromosome 14–26), respectively. The subgenome status for the remaining three markers remained unclear due to their two potential chromosome locations achieved by tertiary monosomic stocks deletion analysis. Chromosomal assignment of these BAC-derived SSR markers will help in integrating physical and cotton genetic linkage maps and thus facilitate positional candidate gene cloning, comparative genome analysis, and the coordination of chromosome-based genome sequencing project in cotton. Disclaimer: Mention of trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by USDA, ARS and does not imply its approval to the exclusion of other products or vendors that may also be suitable. The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.     

现代百合品种培育的技术途径及其杂交特殊现象的机制

为了减少百合(Lilium)育种的盲目性,提高育种效率,本文主要以作者在百合育种工作中的结果和经验为基础,对现代百合品种与野生种的关系、百合组内杂交和组间杂交的差异、现代百合品种的育种途径、非整倍体百合的培育以及百合杂交中特殊现象的机制与新假说(即:百合倍性间杂交的胚乳中含有5个或以上相同基因组是其发育和杂交成功之关键)等方面进行了概述,为百合育种工作者提供有益的参考资料。     

不同倍性苎麻的细胞学观察

化学药剂诱导的苎麻孤雌生殖后代植株的染色体数目变化很大, 有单倍体、 混倍体和非整倍体细胞。 在28株孤雌生殖后代植株中, 有6株单倍体细胞超过50%。 秋水仙素诱变株及多倍体杂交后代的染色体数目也呈现多样性, 不同植株甚至同一植株的染色体数目均不一致, 变化在12～84之间。 对不同倍性苎麻植株分生组织的有丝分裂行     

利用六倍体小黑麦×普通小麦培育伴随易位的非整倍体

用核型和GiemsaC—带技术对六倍体小黑麦×普通小麦的杂种后代（F4）83C3796和83C3804混系今的非整倍体进行了分析。在74个随机抽样的细胞中，染色体数从35条到43条都有分布，比率分别是4．05％、5．40％、2．7O％、9．46％、9．46％、12．16％、12．16％、41．89％和2．70％．发生小麦染色体丢失的植株频率超过55．39％，2n－13植株出现的比率最低（占2．70％）．并从一般核型中观察到染色体游离片段和染色体“断裂一融合”过程．C一带分析观察到高频率的小麦一黑麦染色体易位，都属罗伯逊易位．易位包含了小麦的A、B、D组染色体和黑麦所有14条染色体臂，其中IRS易位频率最高（占48．3％），且全为纯合易位，其它易位染色体纯合的程度各自不同．研究中还观察到在一个细胞中有多个小麦一黑麦染色体易位共存的现象．文中还讨论了易位非整倍体在小麦育种上的利用问题。     

CYTOMIXIS AND CELL FUSION OF POLLEN CELLS IN F_1 HYBRID OF WHEAT CROSSED WITH RYE, WITH REFERENCE TO THE FORMATION OF ANEUPLOIDS

<正> Cytomixis refers to the migration of chromatin from one cell to an adjacent one. The cytological investigation demonstrated that cytomixis and direct fusion of two cells occurred in early stage of pollen development, and resulted from genetic controlled behaviour in hybrid plants of wheat (Triticum aestivum L. cv. Xiaoyuer mai) crossed with rye (Secale cereale L. cv. Winter rye). The frequency of occurrences of cytomixis and cell fusion was about 10％. Spontaneous seed settings in the hybrid plants were obtained.     

水稻非整倍体无性繁殖过程中的遗传稳定性

无性繁殖是保存非整倍体的一个有效手段。为研究该过程中非整倍体的遗传稳定性, 从水稻第8染色体短臂端三体(2n+·8S)自交后代中筛选出相应端四体(2n+·8S+·8S), 其田间性状表现为植株矮小, 叶片非常窄且内卷, 结实率差。在多年无性繁殖过程中, 该端四体所添加的其中1条·8S容易丢失使无性系产生性状变异。通过FISH分析发现该无性变异系的原始系中所添加的2条·8S, 其中1条·8S在着丝粒区域检测不到水稻着丝粒的基本组分CentO序列, 但可以检测到水稻着丝粒的另一基本组分CRR序列, 该染色体可以稳定遗传; 另外1条·8S在着丝粒区域同时检测不到CentO和CRR序列, 该染色体不能稳定遗传。而在最初保存的相应端三体亲本材料的·8S中, 同时包含CentO和CRR序列。说明·8S上的CentO和CRR在多年的组织培养过程中会随机丢失, 导致含有·8S的非整倍体在无性繁殖过程中的遗传不稳定性。     

Cytological and microsatellite mapping of mutant genes for spherical grain and compact spikes in durum wheat

Two mutants for sphaerococcoid seed (MA 16219) and compact spike (MA 17648) were isolated from M₃ progeny of durum wheat cultivar, Altaiskaya Niva, mutagenized with chemical mutagens. The chromosomal locations of the genes involved were determined by the use of a complete set of D-genome disomic substitutions in durum cultivar, Langdon. The gene for sphaerococcoid grain, s ¹⁶²¹⁹ , was allelic to S2, located in the centromeric region of chromosome 3B in hexaploid wheat. The gene for compact spike, C ¹⁷⁶⁴⁸ , was located on chromosome 5AL distal to the Q locus. Using microsatellite markers, C ¹⁷⁶⁴⁸ and awn inhibitor B1 were located in the F₂ of LD222 × MA17648. The gene order was Xbarc319—C ¹⁷⁶⁴⁸ —Xgwm179—Xgwm126—Xgwm291—B1.