普通小麦－华山新麦草异附加系的选育及细胞遗传学研究

利用普通小麦与华山新麦草（２ｎ＝１４,ＮＮ）杂交与回交产生的七倍体杂种（ＡＡＢＢＤＤＮ,２ｎ＝４９）,再与普通小麦回交,即产生单体附加（２ｎ＝４３）,当以七倍体作父本时,产生单体附加的频率（２４．２％）高于七倍体作母本的频率（１２．２８％）。单体附加自交产生二体附加的频率为７．１９％。不同附加系的细胞学稳定性有差异,并随着逐代选择而有所提高。     

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。     

普通小麦——华山新麦草异附加系的选育及细胞遗传学研究

利用普通小麦与华山新麦草（２ｎ＝１４,ＮＮ）杂交与回产产生的七倍体杂种（ＡＡＢＢＤＤＮ,２ｎ＝４９）再与普通小麦回交,即产生单体附加（２ｎ＝４３）当以七倍体作父本时,产生单体附加的频率（２４．２％）高于七倍体母本的频率（１２．２８％）单体了会加自交产生二体附加的频率为７．１９％,不同附加系的细胞学稳定性有差异,并随着逐代选择而有所提高。     

普通小麦与东方旱麦草属间杂种的形态和细胞遗传学研究

本文对普通小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．ｅｖ．Ｆｕｋｕｈｏ,２ｎ＝６ｘ＝４２,ＡＡＢＢＤＤ）与东方旱麦草（Ｅｒｅｍｏｐｙｒｕｍｏｒｉｅｎｔａｌｅ（Ｌ．）Ｊａｕｂ．ｅｔＳｐａｃｈ,２ｎ＝４ｘ＝２８,Ｂ′Ｂ′Ｃ′Ｃ′）属间杂种Ｆ_１进行了形态和细胞遗传学方面的探讨。首先,在形态方面的研究表明：（１）杂种Ｆ_１植株生长旺盛,分蘖力强;（２）绝大部分性状如株高、穗长、芒长等介于双亲之间而呈中间型,少数性状如颖脊、颖壳茸毛可作为鉴别杂种的形态标记;（３）花粉粒空秕、无可染性,花粉高度不育,自交完全不结实。其次,从杂种Ｆ_１的细胞遗传学研究表明：（１）染色体平均构型为：２６．０９Ⅰ＋４．３６Ⅱ＋０．０９Ⅲ,二价体数目从０－７个均有分布,但大多数为棒状二价体;（２）每细胞平均交叉数为４．７８;（３）染色体臂平均配对频率（Ｃ值）为０．１７。由上可知,在普通小麦ＡＢＤ基因组与东方旱麦草Ｂ′Ｃ′基因组之间存在微弱的部分同源关系,或在东方旱麦草基因组中可能存在一种抑制普通小麦Ｐｈ基因作用的抑制因子（ｓｕｐｐｒｅｓｓｏｒ）。     

普通小麦×大麦杂种后代细胞遗传学研究

普通小麦×大麦杂种与普通小麦回交,产生了具有普通小麦细胞质带有部分大麦细胞核的普通小麦－大麦属间杂种后代,对其连续多年套袋自交,测交、细胞学鉴定和定向选择,从自交后代群体中筛选出一部分异附加系、异代换系和易位系街人有大麦某些特性的小析类型,并系统地对本和二体附加系自交后代染色体的分离行为作了遗传分析。结果表明：２ｎ＝４３的单体附加标株自交分离出单体附加的频率为２５．６％,二体附加的频率为１．２％;     

普通小麦：华山新麦草异代换系的选育及细胞遗传学研究

利用缺体小麦－华山新麦草七倍体杂种（２ｎ＝４９,ＡＡＢＢＤＤＮ）杂交,Ｆ１再瑟相应的缺体小麦回交２次,在ＢＣ２Ｆ１镜检选出２ｎ＝４１的植株,同时套代自交,选育出５Ａ和３Ｄ两种异代换系。单体找换植侏自交产生二体代换植侏的频率为２３．１６％。５Ａ代换植侏在减数分裂中期Ⅰ２１Ⅱ的出现频率平均为８４．５２％,３Ｄ代换植侏２１Ⅱ的出现频率平均为６２．６１％。异代换系均生长旺盛,结实正常,说明异染色体能较好地     

八倍体小滨麦与普通小麦杂交后代的细胞遗传学研究

本文对八倍体小滨麦与普通小麦杂交后代的细胞遗传学及附加染色体的传递及丢失规律进行了研究和讨论。结果表明,ＢＣ１Ｆ１与Ｆ２相比较,染色体分离范围小,并且分离向染色体数目减少偏移,有利于４３、４４条染色体的分离;双单体附加和单体附加后代异染色体丢失严重,分别为６５．７９％和６１．９９％,双单体附加分离出单体附加占１０．５３％,单体附加的传递率为２６．９２％,单体附加后代分离出的二体附加为５．５６％,二体附加自交世代中,异染色体的丢失率为２９．０３％,传递率为５６．４５％;ＰＭＣＭＩ染色体构型为２１．７０Ⅱ＋０．０５Ⅰ＋０．０２Ⅲ＋０．０１Ⅳ,２ｎ＝２２Ⅱ的细胞占８８．９６％。选育的附加系及具４２条染色体的株系,不同程度地表现出大穗、大粒、优质、抗病等滨麦的优良性状。     

VE161小麦的外源染色体鉴定

通过染色体原位杂交、ＲＦＬＰ分析和染色体重双端体分析,对在小麦遗传育种研究中具有重要理论和应用价值的ＶＥ１６１小麦不育异代换系及其附加系进行了染色体鉴定。结果表明,ＶＥ１６１小麦代换的或附加的外源染色体为来自长穗偃麦草的４Ｅ染色体,被代换的小麦染色体为４Ｂ。过去曾鉴定为７Ｂ,可能是由于ＶＥ１６１早代染色体易位较多所致。同时发现,ＶＥ１６１小麦在５Ｂ,７Ｂ和１Ｄ所在的３个部分同源群中仍有染色体相互易     

八倍体小滨麦与缺体小麦杂交的细胞遗传学研究

八倍体小滨麦与缺体小麦杂交和回交,其后代ＢＣ１Ｆ１与Ｆ２相比较,染色体分离范围小,有利于４１条染色体类型的分离,若用异源双单体附加作父本与缺体回交,４１条染色体类型的分离率还会提高２倍左右;单体代换在自交世代的传递率为３１．９１％,二体代换的分离率为１９．３７％,异染色体的丢失率为２９．３４％;二体代换在自交世代的传递率为８５．２６％,异染色体的丢失率为９．２１％;ＰＭＣＭＩ染色体构型为２０．７６”＋０．３１’＋０．０３＂＋０．０１””,相对紊乱系数为０．０１,２ｎ＝２１”的细胞占８６．０９％。选育的二体代换系,不同程度地表现出大穗、多花、优质、抗多种病害等滨麦的优良性状。     

一种小麦蓝粒标记单体代换系4E（3D）的创制

以中国春3D单体和小麦-长穗偃麦草4E二体异附加系为材料,通过杂交、回交结合染色体鉴定等方法,培育出了一种具有蓝粒标记的小麦4E(3D)单体代换系.该小麦4E(3D)单体代换系籽粒为浅蓝色,能够正常生长,自交结实率为36.1%,其自交后代可分离出深蓝籽粒小麦4E(3D)二体代换系、浅蓝籽粒小麦4E(3D)单体代换系和白粒小麦3D缺体.结果表明,长穗偃麦草4E染色体对小麦3D染色体缺失有一定的补偿功能,对以染色体定向代换方式快速创制蓝粒标记小麦单体系统具有一定的参考价值.     

大白菜-结球甘蓝5号和8号单体异附加系的筛选和鉴定

为建立成套的大白菜-结球甘蓝异附加系,以大白菜-结球甘蓝异源三倍体（AAC,2n=3x=29）与二倍体大白菜（AA,2n=2x=20）回交世代BC1为材料,对其进行细胞学观察并从中筛选单体异附加系。结果表明,BC1群体植株发生了染色体数目变异,变异范围为2n=20～29,其中以2n=23～24的非整倍体植株居多,占总观察株数的51．44％;对2个2n=21的植株进行核型分析,初步鉴定为大白菜-结球甘蓝5号和8号单体异附加系,分别命名为CO-5—1和CO-8—2。     

四倍体小麦背景中长穗偃麦草E染色体传递特征

通过细胞学方法和染色体特异分子标记鉴定六倍体小偃麦(AABBEE)与硬粒小麦(AABB)杂交的自交后代F₂和F₃植株,探讨长穗偃麦草染色体在硬粒小麦背景中世代间的传递特征,并筛选硬粒小麦-长穗偃麦草E染色体附加系。对218个F₂单株染色体数检测表明,2n=28植株占41.7%,2n=29植株占18.3%,其余40.0%植株的染色体数在2n=31~42范围内。分子标记鉴定表明,在F₂代2n=29单体附加植株中,不同的长穗偃麦草染色体传递率之间存在明显差异,1E传递率最高,3E和6E传递率最低。在F₂代2n=30单株中,1E、4E、7E和5E染色体相互组合产生的双单体多,6E参与组合较少,未检测到2E或3E与其他染色体的组合单株。在1E~7E单体附加株自交后代F₃中,E染色体传递率变化范围为9.1%~27.5%,1E传递率最高,6E传递率最低,与F₂的传递率一致。从F₃代中选育出1E~7E单体附加及少数二体附加,所有单体附加均可育。这些附加E染色体材料将对小麦代换系和易位系的创制提供有益的中间材料。     

A complete set of maize individual chromosome additions to the oat genome

All 10 chromosomes of maize (Zea mays, 2n = 2x = 20) were recovered as single additions to the haploid complement of oat (Avena sativa, 2n = 6x = 42) among F(1) plants generated from crosses involving three different lines of maize to eight different lines of oat. In vitro rescue culture of more than 4,300 immature F(1) embryos resulted in a germination frequency of 11% with recovery of 379 F(1) plantlets (8.7%) of moderately vigorous growth. Some F(1) plants were sectored with distinct chromosome constitutions among tillers of the same plant and also between root and shoot cells. Meiotic restitution facilitated development of un-reduced gametes in the F(1). Self-pollination of these partially fertile F(1) plants resulted in disomic additions (2n = 6x + 2 = 44) for maize chromosomes 1, 2, 3, 4, 6, 7, and 9. Maize chromosome 8 was recovered as a monosomic addition (2n = 6x + 1 = 43). Monosomic additions for maize chromosomes 5 and 10 to a haploid complement of oat (n = 3x + 1 = 22) were recovered several times among the F(1) plants. Although partially fertile, these chromosome 5 and 10 addition plants have not yet transmitted the added maize chromosome to F(2) offspring. We discuss the development and general utility of this set of oat-maize addition lines as a novel tool for maize genomics and genetics.     

小麦-大麦异代换系的创制及鉴定研究

利用"缺体回交法"以小大麦二体异附加系WBA9816作父本与阿勃缺体小麦杂交,创制小大麦异代换系.F1再用该异附加系回交,回交后代通过细胞学鉴定,筛选2n=43的双单体植株套袋自交,从自交后代群体培育出WBS02126;用原位杂交GISH和染色体C-分带技术鉴定表明,WBS02126为2D/2H异代换系;田间试验结果显示,WBS02126生长发育良好,育性基本正常,表现弱春性,叶片宽厚上挺,叶色淡绿,棒状穗,小穗排列紧密,长芒,早熟,综合抗病性好.     

小麦-黑麦附加系的创制及5R抗白粉病新基因的发现

以重复序列pAS1和pSc119.2为探针,对八倍体小黑麦×普通小麦的F5代植株进行了FISH分析,同时对这些材料进行了田间抗病性鉴定。从中鉴定出了1R、2R、3R、4R、5R、6R、7R单体附加系和1R、2R二体附加系,1R和4R附加系出现频率相对较高。5R和6R单体附加系对白粉病免疫,推测5R染色体上带有新的白粉病抗性基因。此外,还检测到不少植株染色体组发生了变异,且小麦4B染色体优先缺失。     

Barley chromosome identification using genomic in situ hybridization in the genome of backcrossed progeny of barley-wheat amphiploids [H. geniculatum All. (2n = 28) x T. aestivum L. (2n = 42)] (2n = 70)

Genomic in situ hybridization (GISH) has been used to study characteristics of the formation of alloplasmic lines detected among self-pollinated backcrossed progeny (BC1F5-BC1F8) of barley--wheat amphiploids [Hordeum geniculatum All. (2n = 28) x Triticum aestivum L. (2n = 42)] (2n = 70). The chromosome material of the wild barley H. geniculatum has been shown to contribute to these lines. For example, fifth-generation plants (BC1F5) had genotypes (2n = 42w + 2g), (2n = 42w + 1g + 1tg), and (2n = 41w + 1g), where w is common wheat chromosomes, g is barley (H. geniculatum) chromosomes, and tg is the telocentric chromosome of wild barley. Beginning from the BC1F6 generation, alloplasmic telocentric addition lines (2n = 42 + 2tg) and (2n = 42 + 1tg) appear. This lines has been found cytogenetically unstable. The progeny of each of these cytological types include not only the (2n = 42 + 2tg) and (2n = 42 + 2tg) addition plants, but also plants with the monosomic (2n = 41 + 1tg) and the disomic (2n = 40 + 2tg) substitutions, as well as the (2n = 41 + 2tg) plants, which lack one wheat chromosome and have two telocentric barley chromosomes. It has been demonstrated that the selection for well-filled grains favors the segregation of telocentric addition lines (2n = 42 = 2tg) and (2n = = 42 + 1tg).     

Identification of Brassica oleracea monosomic alien chromosome addition lines with molecular markers reveals extensive gene duplication

Summary Chromosomes of Brassica oleracea (2n=18) were dissected from the resynthesized amphidiploid B. napus Hakuran by repeated backcrosses to B. campestris (2n=20), creating a series of monosomic alien chromosome addition line plants (2n=21). Using morphological, isozyme and restriction fragment length polymorphism markers (RFLPs), 81 putative loci were identified. Of nine possible synteny groups, seven were represented in the 25 monosomic addition plants tested. Sequences homologous to 26% of the 61 DNA clones utilized (80% were cDNA clones) were found on more than one synteny group, indicating a high level of gene duplication. Anomalous synteny associations were detected in four 2n=21 plants. One of these plants showed two markers from one B. oleracea chromosome associated with a second complete B. oleracea synteny group, suggesting translocation or recombination between non-homologous chromosomes in Hakuran or the backcross derivatives. The other three 2n=21 plants each contained two or more B. oleracea synteny groups, suggesting chromosome substitution.     

Induction of small-segment-translocation between wheat and rye chromosomes

A new approach to produce wheat-rye translocation, based on the genetic instability caused by monosomic addition of rye chromosome in wheat, is described. 1 283 plants from the selfed progenies of monosomic addition lines with single chromosome of inbred rye line R12 and complete chromosome complement of wheat cultivar Mianyang 11 were cytologically analyzed on a plant-by-plant basis by the improved C-banding technique. 63 of the plants, with 2n = 42, were found containing wheat-rye translocation or substitution, with a frequency of 4. 91% . Compared with the wheat parent, other 32 plants with 2n = 42 exhibited obvious phenotypic variation, but their com-ponent of rye chromosome could not be detected using the C-banding technique. In situ hybridization with a biotin-la-beled DNA probe was used to detect rye chromatin and to determine the insertion sites of rye segments in the wheat chromosomes. In 20 out of the 32 variant wheat plants, small segments of rye chromosomes were found being inserted into dif     

Transmission of alien chromosomes from selfed progenies of a complete set of Allium monosomic additions: the development of a reliable method for the maintenance of a monosomic addition set.

Selfed progeny of a complete set of Allium fistulosum - Allium cepa monosomic addition lines (2n = 2x + 1 = 17, FF+1A-FF+8A) were produced to examine the transmission rates of respective alien chromosomes. All eight types of the selfed monosomic additions set germinable seeds. The numbers of chromosomes (2n) in the seedlings were 16, 17, or 18. The eight extra chromosomes varied in transmission rate (%) from 9 (FF+2A) to 49 (FF+8A). The complete set of monosomic additions was reproduced successfully by self-pollination. A reliable way to maintain a set of Allium monosomic additions was developed using a combination of two crossing methods, selfing and female transmission. FF+8A produced two seedlings with 18 chromosomes. Cytogenetical analyses, including GISH, showed that the seedlings were disomic addition plants carrying two entire homologous chromosomes from A. cepa in an integral diploid background of A. fistulosum. Flow cytometry analysis showed that a double dose of the alien 8A chromosome caused fluorescence intensity values spurring in DNA content, and isozyme analysis showed increased glutamate dehydrogenase activity at the gene locus Gdh-1.