偃麦草与小偃麦染色体组构成的细胞遗传学研究V.硬粒小麦与中…

获得了硬粒小麦（２ｎ＝６ｘ＝２８,ＡＡＢＢ）与中间偃麦草（２ｎ＝６ｘ＝４２,ＮＮＥ１Ｅ１Ｅ２Ｅ２）杂种Ｆ１及回交后代材料。统计分析杂种Ｆ１及回交一代ＰＭＣＭＩ染色体配对构型,认为中间偃麦草具较远缘的同亲关系染色体组。由三价体出现频率分析,中间偃麦草不含小麦的Ｂ染色体组,建议用ＮＥ１Ｅ２为其染色体组公式。根据回交一代及其自交后代染色体数目,分析了六倍体小偃麦这一人工新物种的形成过程。     

甘蔗杂种的染色体和RAPD鉴定研究

采用体细胞染色体计数和RAPD (Random Amplified Polymorphism DNA) 分子标记的方法鉴定甘蔗与蔗茅属间杂交种F1的真实性.结果表明,杂种F1材料01/47、01/85、01/120的2n＝80～82,染色体遗传方式为n 2n.用110个随机引物进行RAPD扩增,63个引物可获得双亲的RAPD多态性,其中3个引物OPC-19、OPE-2、OPF-4可在杂种F1材料01/64和01/120的RAPD扩增标记中显示出双亲的特征谱带,分别为父本3500bp和母本1300bp、父本1350bp和母本900bp、父本550bp和母本900bp.     

He-Ne激光对小麦属间杂交影响的研究

1988年以来,作者采用He-Ne激光辐照黑麦花粉与杂交相结合的新方法,对小麦属间杂交(普通小麦×黑麦)进行了研究,获得了较好的效应.试验采用随机区组排列,重复三次,单粒条播.辐照方法,采用He-Ne激光分别以100秒、200秒、300秒辐照三个黑麦品种的花粉,与普通小麦授粉,配制成9个(普通小麦×黑麦)属间杂交组合.所得结果,采用方差分析、新复极差测验法,测定了组合与对照组合相比的差异显著性,也测定了各组合间相互比较的差异显著性.激光辐照小麦属间杂交所获种子的结实率极显著高于对照,为113.52～341.60%.籽粒千粒重和饱满度均超过对照,分别为84.07～295.43%、30.30～127.27%,差异均极显著.L1代籽粒出苗率和植株成活率分别比对照提高58.18～83.06%、41.35～87.78%,差异达到极显著水平.He-Ne激光的诱变作用,在于促进了小麦属间杂交的可交配性,提高了杂交籽粒的结实率,改善了籽粒的饱满度,提高了籽粒的千粒重,因而促进了杂种种子的出苗率和成活率.并且,在L1代植株中均获得了染色体自然加倍的双二倍体即小黑麦种子.现已获得L1～L8代的小黑麦后代材料和稳定株系.高科技的激光诱变育种,为小麦属间杂交育种工作开辟了新的简便途径.     

单倍体小麦与羊草的属间体细胞杂交

以失去植株再生能力的小麦单倍体愈伤组织和羊草二倍体愈伤组织为材料,游离原生质体,并用紫外线自理２羊草原生质体,用ＰＥＧ法融合,对融合克隆进行染色体和同工酶分析,在已贩２６个克隆中有２１个是杂种,其中有一个克隆再生出短命小植株,结果 体小麦与二倍体草的不对称融合虽然再生互补效应不如二倍体小麦,然而杂种优先生长的现象仍然比较明显。如果改善实验条件和双亲原始的再生能力,这种融合方式仍然可以利用。     

披碱草与新麦草属间杂种的细胞遗传学研究

将澳大利亚披碱草(Elymus scabervar.scaber,2n=6x=42,StYW)和华山新麦草(Psathyrostachys huas-hanica,2n=2x=14,Ns)进行属间杂交,成功获得杂种F1。分析亲本及其杂种F1的形态特征、繁育特性及花粉母细胞减数分裂染色体配对行为发现:杂种F1形态特征介于父母本之间,分蘖数等农艺性状超过双亲;花粉完全不育,结实率为0。亲本减数分裂染色体配对正常,但杂种F1花粉母细胞在减数分裂中期I染色体几乎没有配对,其构型为:27.31Ⅰ 0.01Ⅱ(环) 0.32Ⅱ(棒) 0.01Ⅲ,C值仅为0.01。以上结果表明:澳大利亚披碱草的StYW染色体组与华山新麦草的Ns染色体组间无同源性,它们之间的亲缘关系甚远。     

Paranepheliinae亚族(菊科,Liabeae族)的系统发育和可能的属间杂交

The nuclear ribosomal ITS region and the chloroplast trnL-trnF (trnLF) intergenic region were sequenced for 45 accessions of Paranephelius and six accessions of Pseudonoseris, the two genera of the subtribe Paranepheliinae (Liabeae, Asteraceae) distributed in the alpine regions of the Andes. This data set was used to estimate relationships between these genera and within each genus to aid in evaluating morphological variation and classification. Our results with both ITS and trnLF markers support the monophyly of subtribe Paranepheliinae, and place Pseudonoseris discolor as the first diverged taxon sister to the clade containing Paranephelius. Pseudonoseris szyszylowiczii exhibited intraspecific divergence supporting intergeneric hybridization between Pseudonoseris and Paranephelius. Within Paranephelius, genetic divergence is low and not adequate to fully resolve phylogenetic relationships at the species level, but two genetically and morphologically recognizable groups were revealed by the ITS data. Several accessions possessing multiple ITS sequences represent putative hybrids between the two groups. These putative hybrids have caused some taxonomic confusion and difficulties in establishing species boundaries in Paranephelius. The divergence time estimates based on ITS sequences indicated that the stem of subtribe Paranepheliinae dates to 13 million years ago, but the diversification of the crown clade of the extant members began in the early Pleistocene or late Pliocene, perhaps associated with the uplift of the Andes and the climatic changes of global cooling.     

长芒猬草与华山新麦草属间杂种的形态学和细胞学研究

为研究长芒猬草Hystrix duthiei ssp．longearistata的染色体组成,将其与华山新麦草Psathyrostachys huashanica进行了人工杂交,获得杂种F₁。对亲本及杂种F₁,花粉母细胞减数分裂染色体配对行为、繁育 特性和形态特征进行了比较分析。结果表明：杂种F₁的许多形态特征介于父母本之间,花粉完全不育, 结实率为0;杂种F₁花粉母细胞减数分裂中期Ⅰ染色体配对较高,55.12％的细胞形成5个或6个二价 体,其构型为：9.83Ⅰ+5.46Ⅱ+0.07Ⅲ,C-值为0.57。以上结果表明H．duthiei ssp．Longearistata含有Ns染色体组。本文还讨论了Hystrix与Leymus的关系。     

白菜型油菜,芥菜型油菜与诸葛菜的属间杂交合子胚的组织培养

TissueCultureofZygoticEmbryosofIntergenericHybridizationAmongBrassicacampestris,B．junceaandOrychophragmusviolaceusWUYan－You,JIANGJiu－Yu（InstituteofGeochemstry,TheAcademyofScience,Guiyang550002）1植物名称白菜型油菜（Brassicacampestris）品种川油8号（2n=20）、芥菜型油菜（B.juncea）品种沪州四棱（2n=36）和诸葛菜（Orychophragmusviolaceus,2n=24）。2材料类别白菜型油菜和芥菜型油菜作母本,诸葛菜作父本,人工授粉22d“萝卜”角果中的未成熟杂种胚。3培养条件分化培养基为MS＋6-BA2mg／L（单…     

白菜型油菜与蓝花子的属间杂交合子胚组织培养

TissueCultureofZygoticEmbryosofIntergenericHybridizationBetweenBrassicacampestrisandRaphanussativusvar．raphanistroidesWUYan-You,JIANGJiu-Yu（InstituteofGeochemstry,TheChimeseAcademyofScience,Guiyang550002）1植物名称白菜型油菜（Brassicacam－pestris）品种川油8号（2n=20）和蓝花子（Raphanussativusvar．raphanistroidesMakino,2n＝18）。2材料类别白菜型油菜作母本,蓝花子作父本,人工授粉22d“萝卜”角果中的未成熟杂种胚。3培养条件分化培养基为MS＋6－BA2mg／L（单位下同）＋NAA0．1;生根培…