高粱体细胞无性系变异的筛选与利用

选用幼穗、幼胚、茎尖等五种外植体进行组培,结果表明,幼穗和幼胚的分化率最高,最适宜选用进行高粱体细胞克隆变异利用研究。对9个高粱品系的166个R2代株系进行了观察分析,除两个品系外,其余7个均有变异株系出现,其中晋粱5号的变异频率高达26%,9个品系的平均变异频率为11.24%。筛选到多个高粱骨干恢复系的无性系变异材料,并且以优良变异系R111为父本育成了优良杂交种一个,已通过审定,定名为晋杂18号。     

不同来源高粱品系农艺性状及品质性状遗传多样性分析

选用来自中国、美国、印度的61份高粱品系作为试验材料,采用随机区组设计,成熟期对高粱的9个性状进行统计分析和聚类分析。研究表明,不同品系间性状表现具有丰富多样性,其中生育期和淀粉的变异程度最低,株高、穗长、单宁的变异程度较大,穗粒重、千粒重、粗蛋白、脂肪的变异程度较为明显。株高、穗粒重与穗长呈显著正相关,千粒重与穗粒重呈极显著正相关,单宁、粗蛋白与脂肪呈极显著正相关,单宁、粗蛋白、脂肪与总淀粉呈极显著负相关。聚类分析结果显示,61份高粱品系可划分为三个类群,各类群都表现出独特的地域性特征。供试高粱品系的农艺性状和品质性状均有着巨大的改良潜力,为进一步改良高粱品种和亲本选育提供科学依据。     

高粱DNA导入水稻后代主要性状分析

本研究利用花粉管通道法,将高粱无融合生殖系SSA-1 (Shanxi sorghum apomict-1)的全基因组DNA导入水稻‘辽盐28号’、‘辽盐6号’两个品种,子代的遗传性状发生了明显变化,经过连续自交选择和鉴定,获得了27个表型稳定的D_4代株系。通过田间种植,对导入株系的抽穗期、分蘖数、株高、千粒重等农艺性状的表型进行了统计分析。结果表明:D_4代株系的农艺性状存在广泛变异,部分D_4代株系茎秆、穗粒颜色更偏向供体高粱,表明高粱全基因组DNA成功导入受体细胞,并对受体基因的表达产生了影响,与受体亲本相比,导入株系在抽穗期、分蘖数、株高、每穗粒数、每穗粒重、穗长、千粒重等主要性状上都表现出明显变异。进一步对变异株系分析筛选有助于挖掘新种质材料,为选育水稻新品种提供丰富的种质资源。     

小麦无性系抗赤霉病突变体2870

在崇阳红麦×鄂恩一号杂交当代14天胚龄的幼胚离体培养获得的再生植株R2代中,选得抗性较好的1个单株。1989年(湖北省该年为赤霉病大流行年)种的为R3株系,编号为2870,经麦穗接种赤霉病菌分生孢子,抗性表现突出,仅接种小花发病至该小穗病,未扩展至穗轴。早熟(5月中下旬收获)、中秆(88cm),每穗20个小穗。R4代按接种穗     

高粱转基因再生体系建立初探

为建立高粱转基因再生体系,本研究以XL52、‘三尺三’、M81-E、07-27、BJ-285幼穗和幼胚的愈伤组织及幼胚为材料,利用农杆菌介导法进行高粱转Bar基因转基因体系研究。结果表明:以XL52幼胚、XL52和M81-E幼胚愈伤组织、‘三尺三’幼穗愈伤组织为外植体转化都获得了抗性愈伤组织,通过分化培养只有XL52幼胚转化所获得的愈伤组织获得转基因苗。本研究成功获得了抗性愈伤组织,为以后高粱转基因再生体系建立提供借鉴。     

水稻籼粳杂交BC2F5代株系花药培养H2代株系的主要变异性状分析

通过对水稻籼粳杂交BC2F5代10个株系进行花药培养,在494个H2代株系中选择出32个变异株系进行变异性状分析,我们将其分离变异样式归为简单分离变异和激烈分离变异两大类.其中简单分离变异型以株高变化为标准又划分为3个亚类,即:株高变矮且其他性状发生变异;株高不变但其他性状发生变异株高变高且其他性状发生变异.激烈分离变异型的变异样式类似F2分离模式.我们进一步对株高、育性、穗伸出度、千粒重、着粒密度、穗型、穗芒、抽穗期等性状的变异频率进行了分析,发现株高、育性和穗伸出度的变异频率较高,着粒密度和抽穗期次之,变异频率最小的是穗型、千粒重和穗芒.     

组织培养途径改良定型小麦品种的研究

选用ＣＡ９０７０、ＣＡＤ８６９４,京４１１三个定型品种进行组织培养,比较了三种培养方式的培养效果,调查了Ｈ２,Ｒ２株系主要农艺性状的遗传变异情况,结果表明,幼胚培养效率最高,基因型间差异小,花药培养的基因型间差异显著,花药培养后代农艺性状的变异率高于幼胚培养,且其性状值向更小的方向变异,而幼胚培育诱花的变异范围大于花药培养,获得了ＣＡＤ８６９４的花培变异株系９５Ｈ０５５,株高降低了１１．５ｃｍ,获     

外源DNA导入水稻后代变异性的SSR分析

采用花粉管通道法,将高粱DNA导入水稻,获得了34个稳定的变异品系,从60对SSR引物中筛选出17对,对供体高粱、受体水稻及其外源DNA导入后代稳定材料进行了SSR分析,结果表明,高粱DNA导入水稻可以引起广泛的变异,在分子水平上产生了遗传多样性,聚类分析可将其分为五类,各类有其特有的遗传变异性。接受外源DNA三个片断,两个片断及一个片断的株系分别被聚成一类,与其他类的遗传差异分别为0.467,0.389及0.347,变异程度依次递减;未接受外源DNA两个片断的株系被聚成另一类。因此,接受外源DNA片断的多寡是水稻后代稳定品系变异程度的基础,也是它们分类的标准。     

幼穗无性系变异在小麦育种上的应用

冬小麦(综抗矮6号×泰山1号)F_1代花培H_1代纯系经幼穗离体培养建立的13—7管无性系获得一株R_0代种子,后代变异类型多、频率高,其R_2、R_3代株高、抽穗期都呈一个正态分布、连续性变异,调查的几个性状在R_3代稳定率已达84.85—100％。已从稳定品系中选择出一批不同株高和高蛋白材料,其中4个品系比对照冀麦6号增产17.2—35.8     

小麦-黑麦远缘杂交后代高分子麦谷蛋白亚基变异分析

采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE) 方法, 分析了小麦-黑麦远缘杂交后代的66个株系的高分子量谷蛋白亚基(HMW-GS) 组成.结果表明:(1)在29个母本为MY 11的株系中,有6个株系的Glu-1等位基因相对于母本MY 11发生了变异,1 B/1 R易位系中Glu-1位点发生变异的频率为66.67%,非1 B/1 R易位系中Glu-1位点发生变异的频率为8.69%.在36个母本为A 42912株系中,3个株系的Glu-1等位基因发生变异且这3个株系皆为1 B/1 R易位系,1 B/1 R易位系中Glu-1位点发生变异的频率为60.0%,非1 B/1 R易位系Glu-1位点没有变异;(2)对于母本为MY 11的株系,Glu-1三个位点上等位基因的变异均只有2种,即Glu-A 1 a(86.20%)、Glu-A 1 c(13.79%)、Glu-B 1 b(89.65%)、Glu-B 1 c(10.34%)、Glu-D 1 a(3.45%)、Glu-D 1 d(96.55%).对于母本为A 42912的株系,仅在Glu-B 1位点发生变异,即Glu-B 1 b(91.66%)、Glu-B 1 c(8.33%);(3)供试株系共出现6种高分子谷蛋白亚基组合,即(1,7 8,5 10)、(Null,7 8,5 10)、(Null,7 9,5 10)、(Null,7 8,2 12)、(1,7 8,5 10)、(1,7 9,5 10),两种母本不同的株系类型均是母本型HMW-GS组合(1,7 8,5 10)占绝对优势.本文分析了1 B/1 R易位株系具有高频率HMW-GS变异的原因,并就这些材料在小麦优质育种中的利用策略作了探讨.     

高粱不同外植体离体培养

不同材料愈伤组织诱导培养结果表明，幼穗，茎尖和成熟胚的最高出愈率达１００％，子粒达９３％，幼胚仅为７４％。幼穗不但出愈率高，且愈伤组织胚性状况好，分化出苗率高。幼胚出愈率虽低，但其分化率明显主茎尖，成熟胚和子粒了的分化率。     

In Vitro Culture of Hybrid Indica Rice Combined with Mutagenesis

The mutagenic effects of gamma radiation and sodium azide (SA) immersion of explants on culturability and frequency of somaclonal variation in indica rice were investigated. The results showed that young inflorescence and mature embryo were satisfactory explants both for in vitro culture and for mutagenesis. 1 kR gamma rays applied to immature embryos and exposure of calli derived from mature seeds at the dose range of 250—500 R led to a higher rate of callusing and plantlet regeneration, 0.5—1 kR would be the appropriate exposure for young inflorescence to produce a better culture response and higher variability, and 2.5—5.0 kR the optimal dose range for mature embryos. Immersion of mature seed in 2—4 mM sodium azide solution is a concentration level to induce these effects in indica rice. Application of optimal gamma exposure and chemical mutagen to rice explants enhanced the somaclonal variation frequency and provided a large number of variants useful for rice breeding.     

我国部分主推小麦品种组织培养再生能力评价

小麦细胞工程育种和基因工程育种存在强烈的基因型特异性, 从目前推广的优良小麦品种中筛选不同外植体再生能力强的基因型, 对于提高小麦生物技术育种效率和加速育成品种的生产应用具有重要意义。本研究以全国大面积推广的24个优良小麦品种和抗白粉病优良品系CB037为材料, 连续2年进行花药培养、幼胚培养和成熟胚培养, 统计愈伤组织诱导率、愈伤组织分化率和植株再生率, 分析、评价这些小麦品种(系) 3种外植体的组织培养再生性能。结果表明, 25个小麦品种(系)花药、幼胚、成熟胚的植株再生率分别为0~41.75%、2.25%~531.92%和3.24%~84.34%, 基因型差异显著; 组织培养再生能力以幼胚最强(119.79%), 成熟胚其次(36.23%), 花药最弱(4.91%)。CB037的3种外植体组织培养再生效率均最高, 轮选987、扬麦16、内麦836、科农199、新春6号、郑麦366、郑麦9023、新冬20、烟农19和川麦42幼胚培养植株再生能力表现较强, 新春6号、京冬8号、石麦4185、科农199和轮选987成熟胚培养植株再生率较高, 石麦4185和邯6172花药培养绿苗诱导率较高。小麦组织培养效率与基因型和外植体类型密切相关, 不同品种同一外植体再生能力差异显著, 同一品种不同外植体再生能力也存在显著差异, 并且3种外植体的组织培养再生能力不存在相关性。本研究筛选到不同外植体再生能力较好的优良小麦基因型, 可进一步用于小麦转基因育种和单倍体育种。     

谷子体细胞无性系变异及其在育种上的应用

本研究对谷子(Setaria italica Beauv.)7个品种的体细胞无性系性状变异和遗传进行了分析. 结果表明: 以R2株系为计算单位的谷子体细胞无性系农艺性状变异频率平均为13.0%, 不同基因型的变幅为4.3%～32.9%; 变异涉及株高、抽穗期、穗粒重、出谷率、育性、抗病性、米色等多个性状; R1代表现半不育的植株, 其R2代出现变异的机率     

Progress made in FEC transformation of cassava

In cassava friable embryogenic callus (FEC) has been used to obtain transgenic plants using particle bombardment, electroporation, and Agrobacterium tumefaciens. FEC cultures have been obtained in 6 of the10 tested genotypes. In all genotypes FEC could be regenerated into plants,however the efficiency differed between the genotypes. Almost all plants regenerated from 6 months old FEC cultures of TMS604444, Adira 4,Thai 5 and M7 were morphological similar to control plants. However, in R60 and R90 a large number of plants were not identical to control plants. Older FEC lines of TMS60444 have a reduced ability to regenerate plants and the plants show somaclonal variation. Somaclonal variation is observed in the same extend in transgenic and non-transgenic plants. The origin of this variation is both genetic and epigenetic. Luciferase based selection is less efficient in producing transgenic lines than chemical selection. Furthermore Agrobacterium tumefaciens mediated transformation is much more efficient than particle bombardment with respect to the production of transgenic lines. A tentative model is introduced which best describes the effect of different selection regimes on the time period required to produce transgenic plants. Kanamycin and stringent luciferase selection required a shorter period of time than selection based on hygromycin, phosphinothricin or non-stringent luciferase. However, a more significant reduction of time was obtained if young instead of old FEC lines of genotype TMS60444 were used for genetic modification. In accordance to the model these young FEC lines of TMS60444 produced transgenic plants within 4 months with both Agrobacterium tumefaciens combined with kanamycin selection and particle bombardment combined with stringent luciferase selection. This revised version was published online in July 2006 with corrections to the Cover Date.     

Improvement of somatic embryogenesis and plant regeneration from durum wheat (Triticum turgidum var. durum Desf.) scutellum and inflorescence cultures

Scutellum and inflorescence explants of four genotypes of durum wheat(Triticum turgidum var. durum Desf.) were used to define culture conditions to obtain high frequencies of embryogenesis and plant regeneration in vitro. Under all conditions tested, scutellum cultures gave higher frequencies of embryogenesis and plant regeneration than inflorescence cultures. Two different auxins, 2,4-D(2,4-dichlorophenoxyacetic acid) and picloram(4-amino-3,5,6-trichloropicolinic acid), were compared for their effect on scutellum and inflorescence explant response in vitro. Picloram was found to significantly increase the frequency of plant regeneration from both explants. When cultures were grown on regeneration medium containing zeatin for two three-week passages, the frequency of plant regeneration increased by between 20–30% compared with cultures exposed to hormones for a single three-week passage. Finally, the addition of 1 mg/l 6-BAP (6-benzyl aminopurine) to the plantlet growth medium was found to enhance tiller production in regenerants. The optimized culture conditions were applicable to the four genotypes tested and frequencies of plant regeneration varied between 97% to 100% for scutellum cultures (2 mg/l picloram in induction medium) and between45% and 80% for inflorescence cultures (4 mg/l picloram in induction medium). The number of plants regenerated per explant was improved over previous procedures, with means of 34 plants per scutellum, and 16 plants per inflorescence explant. This revised version was published online in July 2006 with corrections to the Cover Date.     

高粱体细胞克隆变异化学诱导方法研究

高粱组培育种仍以传统的常规培养技术为主,变异属于自然发生,变异频率不太高,因而制约了该方法应用的有效性。此研究旨在通过采用化学方法进行人工诱变以期达到提高诱变率的目的,采用的试验材料以高粱主要恢复系三尺三和晋粱5号为主,诱变剂以硫酸二乙酯为主。由于对生物体具有诱变效果的化学物质一般对人体具有很大毒性,所以探索安全无污染的处理方法则是非常必要的。通过几年的研究探索,达到了预期的目的,创立了有毒化学物质安全无污染诱变处理方法,同时明确了硫酸二乙酯诱变处理高粱愈伤组织的浓度一般为0.5%~1%。