用气孔保卫细胞叶绿体计数法鉴定烟草染色体倍性方法初探

经不同浓度秋水仙碱液加倍处理的烟草花粉植株，用叶片气孔保卫细胞叶绿体计数法鉴定染色体倍性。研究表明：气孔保卫细胞叶绿体数平均值差异极显著，单倍体95％以上的叶绿体数在14个以下，双倍体95％以上的叶绿体数则在14个以上。经开花结实验证其准确率达91％，且展开到第5叶时就可鉴定。     

水稻多倍性育种中的倍性鉴定方法研究

从水稻花粉粒、植株形态、种子形态和染色体计数等方面分别对不同倍性水稻植株的染色体倍性进行了鉴定.鉴定结果表明,随着细胞染色体倍性的增加,植物细胞和器官体积一般趋于增大,水稻花粉粒大小与染色体数目和倍性存在正相关性,可作为鉴定水稻倍性的参考指标;水稻植株形态和籽粒大小、芒的有无、着粒密度和结实率高低等性状与染色体倍性同样具有相关性,亦可作为鉴定水稻倍性的参考指标.     

黄瓜染色体制片及倍性研究

以黄瓜卷须为材料，对黄瓜染色体制片中的一些主要参数和方法进行了研究，建立了黄瓜染色体制片的系统操作规程。研究发现，黄瓜染色中心直径和异染色质数目与植株倍性呈正相关，可作为黄瓜倍性鉴定的间接指标，其中单倍体染色中心直径平均为5．1μm，双单倍体为13．3μm，单倍体异染色质数目平均5．0，双单倍体为11．9。     

燕麦染色体C—分带研究

以二倍体燕麦Ａｖｅｎａ ｓｔｒｉｇｏｓａ为材料，进行染色体Ｃ－分带方法研究，确定了最佳分带流程。以Ｇｉｅｍｓａ与Ｗｒｉｇｈｔ混染效果最好，Ａ．ｓｔｒｉｇｏｓａ的７对染色体Ｃ－带差异明显，各对染色体带型互异，但都有两条端带，对每要色体的Ｃ－带特征作了分析。最后讨论了影响Ｃ－分带效果的因素及燕麦染色体Ｃ－分带的意义。     

组织培养中大葱染色体倍性变异的研究

采用大葱茎尖分生组织直接成苗及分化丛生苗、茎盘诱导愈伤组织培养再生植株,通过染色体压片,对大葱愈伤组织及幼苗染色体数目变化进行了研究。结果表明,茎尖分生组织培养的幼苗及丛生苗遗传稳定,其染色体未发生倍性变异,均为2n=16;愈伤组织及其再生苗遗传稳定性较差,愈伤组织染色体数变异率为43.4%,其中单倍体占6.7%、三倍体占2.5%、四倍体占10%、五倍体占4.2%、六倍体占3.3%、七倍体占4.2%、八倍体占3.3%、非整倍体占9.2%;愈伤组织分化苗染色体变异率为11.7%,其中单倍体占6.7%,三倍体占1.7%,四倍体占3.3%。     

西葫芦胚囊再生植株的倍性鉴定

通过气孔保卫细胞叶绿体记数法和流式细胞仪测定法对西葫芦胚囊再生植株进行了倍性鉴定。结果表明：气孔的大小、形态和胚囊再生植株的倍性比例因基因型而异．而气孔叶绿体数量及其密度不受基因型的影响。气孔类型相同的胚囊再生植株．两种方法鉴定的倍性一致率较高：其中类型1和2为100％．类型3为80％。流式细胞仪测定法适宜于大批量材料的鉴定,方便、快捷且准确,但费用较高：气孔保卫细胞叶绿体记数法是初步鉴定倍性的有效手段。     

与燕麦耐冬性有关的细胞标记

秋播和春播六倍体燕麦（Avena sp．）种质中出现不同频率的染色体组间易位T7C-17。本试验的目的是评估品种Wintok（有T7C-17，具耐冬性）和Fulghum（无T7C-17，耐冬性稍差）杂交后的94个F4代随机衍生系的根冠分生组织的耐冻性和冬季田间成活率。并检验这些耐冬性性状与T7C-17的相关关系。在人工控制环境生长室内采用3次重复随机完全区组设计，评估这些衍生系的根冠分生组织的耐冻性。     

辣椒花药培养再生株群体染色体倍性构成的多样性

采用流式细胞分析术和染色体计数法对辣椒花药培养再生株群体的染色体倍性构成情况进行了鉴定。显示了花药培养再生株中染色体倍性构成的多样性。观察到染色体倍性在不同检测组织器官中的差异现象,说明对同一材料不同器官进行倍性检测以确定植株倍性的必要性,以及植株上部器官的染色体倍性对于结籽能力的决定性。观察到再生株中个别细胞染色体的丢失现象。对流式细胞检测技术和染色体计数法的相关性进行了研究,得出2种检测技术下二者的吻合度为0.95,并对流式检测技术中的偏峰现象进行了初步的分析。     

一种野生燕麦的染色体核型分析

对安徽风阳地区麦田里的一种野生燕麦的染色体核型进行了分析，结果如下：该物种的染色体数为2n=42，各染色体间形态差异明显，但均为中着丝粒染色体（m）或近中着丝粒染色体（sm），最长与最短染色体相对长度比为2．34，并在全套染色体中的第9号和16号染色体上发现了2对随体，核型公式为2n=6x-42=22m＋20sm（2SAT），核型类型舅比较对称的2B型。同时讨论了燕麦作为小麦遗传改良的重要种质资源，对普通小麦远缘杂交和品质改良的意义。     

二倍体野燕麦染色体的C-带分析

采用C-带技术对二倍体野燕麦根尖细胞染色体进行了带型分析,以研究该野燕麦染色体的C-带特点.结果表明:二倍体野燕麦具有7对染色体,其上共有35条带,其中长臂具有带纹19条,包括13条中间带(I),6条末端带(T);短臂具有8条带纹,包括2条中间带(I),6条末端带(T),另外还有l条随体带(S)以及7条着丝点带(C),其带型公式为2 n=14=2CIT+ +2 CIT+8 CI+ T+2 CI+ T+S.二倍体野燕麦染色体组成为CC,核型为2A,属于较对称核型,进化指数为7.     

The Use of Stomatal Chloroplast Number for Rapid Determination of Ploidy Level in Maize

The usefulness of using the chloroplast number in epidermal guard cells as an indirect ploidy indicator was evaluated on seed-grown and tissue culture-derived maize plants. For seed-grown plants, two maize genotypes (B89 and R75) which had both diploid and tetraploid seeds available were used as experimental materials. The ploidy levels of seed-grown plants were confirmed by flow cytometric analysis of nuclear suspensions from these plants. For regenerated plants, haploid and diploid levels were examined and the ploidy levels of these plants were determined by chromosome counts of cells from root tips. A positive relationship between the chloroplast number and ploidy level was observed for both seed-grown and regenerated plants. The stomatal guard cells of tetraploid plants had nearly double the number of chloroplasts as the diploid plants. Similar results were found from the regenerated plants. The differences in the mean chloroplast number between diploid and tetraploid seed-grown plants and between haploid and diploid regenerated plants were highly significant. The results of this study demonstrate that counting chloroplasts in guard cells can be an efficient means of screening a large number of plants for ploidy levels. In addition, this study suggests the possibilities of using this method for detecting contaminated seed lots by different ploidy seed and for distinguishing plants of different genotypes.     

Chromosome Studies in the Genus Alstroemeria

Chromosomes of 11 cultivars of Alstroemeria were studied to determine their somatic constitutions. Two cultivars, ‘Eureka’ and ‘Zebra’, were diploid (2n = 2×= 16), six cultivars, ‘Yellow King’, ‘King Cardinal’, ‘Mona Lisa’, ‘Appelbloesem’, ‘Pink Triumph’ and ‘Rosita’ were triploid with 2n = 3×= 24, one cultivar, ‘Orange Beauty’ was a hypertriploid (2n = 3×+ 1 = 25), one cultivar, ‘Luciana’ was a hypotetraploid (2n = 4×– 1 =31) and one cultivar, ‘Jubilee’, was true tetraploid (2n = 4×= 32). This result suggests that polyploid cultivars may have more market value in this cut flower, Alstroemeria.     

河北省桑属植物染色体倍数性研究

研究了桑属植物５个种３２个品种的染色体倍数性，发现宽城１０号等９个品种为三倍体（２ｎ＝３ｘ＝４２），其余为二倍体（２ｎ＝２ｘ＝２８）。     

Determination of the Ploidy Level of Pure and Mixed Plant Populations of Sugar Beet (Beta vulgaris L.) by Flow Cytometry

To improve estimates of the true ploidy level of pure diploid triploid, and tetraploid sugar beet (Beta vulgaris L.) plants, and of populations of mixed ploidy, the effect of leaf age/size was evaluated on ploidy determination by flow cytometry. There were significant differences between old and young leaves, with young leaves giving the best estimate of the true ploidy level of the plants. The old leaves seemed to express a high degree of endopolyploidy.     

Determination of Ploidy of Single Plants and Plant Populations by Flow Cytometry

An efficient method for the determination of the ploidy level is described, based on a measurement of the DNA content of interphase nuclei by flow cytometry. Both individual plants as well as plant populations can be used to obtain the desired DNA-histograms Compared to conventional chromosome counting flow cytometry turned out to be highly competitive in terms of simplicity, accuracy, and costs.     

西葫芦胚囊再生植株倍性鉴定方法研究

利用根尖细胞染色体压片和叶片保卫细胞叶绿体压片方法对西葫芦胚囊再生植株进行了倍性鉴定,结果表明,单倍体、二倍体和四倍体植株叶片表皮保卫细胞叶绿体数的均值分别为(4.15±0.37),(8.05±0.76)和(16.05±0.69),其比例约为1:2:4,说明叶片保卫细胞叶绿体压片方法能有效用于倍性鉴定;单倍体、双单倍体和四倍体叶片表皮保卫细胞的长度分别为(20.31±3.38)μm、(30.80±2.19)μm和(41.78±1.03)μm,其比例约为1:1.5:2,在胚囊再生植株倍性鉴定时也可以参照。     

流式细胞术在植物学研究中的应用——检测植物核DNA含量和倍性水平

流式细胞仪作为高效的检测工具,在植物学研究的多个领域都发挥了重要作用。兰州大学干旱与草地生态教育部重点实验室分子生态所通过大量的植物流式细胞术实验,针对检测植物核DNA含量和倍性水平,总结出一套详细通用的实验方法。同时着重阐述了各个实验环节的关键点。分析因碎片过多而导致实验失败的原因,并提供了切实可行的解决方法。对今后检测各种植物具有重大指导意义,同时也促进了流式细胞术在植物学研究中的应用。     

不同因素对小麦根尖染色体制片的影响

以小麦根尖为材料,探讨了低温、秋水仙素、8-羟基喹啉和对二氯苯4种预处理对小麦根尖细胞有丝分裂积累中期分裂相的效果.结果表明,这4种预处理方法积累有丝分裂中期分裂相效果的明显程度由大到小依次为秋水仙素、低温、对二氯苯和8-羟基喹啉,前2种方法效果明显且差异不大,后2种方法效果略差.在此基础上,对低温预处理后的根尖在制片过程中的一些因素进行了摸索,发现影响制片效果的主要因素是低温预处理时间和HCl解离时间.最终得到以小麦根尖为取样对象的体细胞染色体制片的最适方法.为小麦族物种的染色体加倍、异染色体系的鉴定、细胞遗传学研究等领域提供方法依据.     

Short-duration colchicine treatment for in vitro chromosome doubling during ovule culture of Beta vulgaris L.

Colchicine uptake into ovules of sugar beet after 7 days of culture and its chromosome-doubling effect on ovule-derived plants were studied with high colchicine concentrations (0.4–6.0%) and short treatment duration (0–5 h). The best result of 4.2 diploid plants per 100 ovules was produced by treatment with 0.4% colchicine for 2.5 h. Both colchicine concentration and treatment time of ovules showed toxic effects on embryo formation, but it was stabilized at a low level with short exposure. The chromosome-doubling effect, by contrast, was unchanged with the colchicine concentrations used, but highly affected by the duration of exposure studied. A maximum percentage of 60% diploid plants was obtained after 3–5 h of uptake, which corresponds to only 31–39% of the total capacity for colchicine uptake in the ovules. Further uptake of the drug produced mainly toxic effects. Flow-cytometric measurements of the ploidy level in plantlets in vitro and of the same plants before flowering in soil were similar in about 80% of cases. Thus, flow-cytometric selection of diploid plants in vitro may be an efficient tool.     

甘蓝未受精子房离体培养及再生植株倍性的鉴定

甘蓝通过未受精子房离体培养诱导获得的再生植株,对再生植株的倍性进行有效的鉴定是将其进一步应用于优良品种选育的基础。本研究利用3种基因型的甘蓝材料(PMQM、QMF、RMQM)培育再生植株,优化甘蓝未受精子房离体培养体系,并通过形态学鉴定法、根尖染色体计数法、流式细胞仪鉴定法对组培植株进行倍性鉴定。结果表明:在0.4 mg/L ZT的分化培养基中,3种基因型材料的愈伤组织分化率明显高于1.0 mg/L 6-BA培养基中的组培苗,其中基因型RMQM的分化效果最好;最终确定诱导愈伤组织分化不定芽的最适培养基配方为MS+0.4 mg/L ZT+2.0 mg/L 2,4-D+0.1 mg/L NAA,且通过3种鉴定方法,得出再生植株倍性:单倍体3.4%,双倍体49.8%,四倍体15.9%,嵌合体35.3%。