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91.
92.
长芒猬草与华山新麦草属间杂种的形态学和细胞学研究 总被引:14,自引:0,他引:14
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。 相似文献
93.
以生产上应用的耐湿性存在差异的3个甘蓝型油菜品种为对照,采用盆栽模拟湿害胁迫的方法,对15份源自甘蓝型油菜与蔊菜属间杂交获得的遗传稳定的创新种质进行苗期耐湿性鉴定和综合评价。结果显示:(1)湿害抑制根系生长,导致植株变矮,叶片发黄,生物量降低,湿害对根系影响最为严重,其次是植株总生物量积累和地上部分的生长。(2)通过主成分分析和隶属函数法,将全展叶数、绿叶率、苗高、根长、地上部分鲜重、根鲜重、植株总鲜重、地上部分干重、根干重和植株总干重等10个性状指标值转化成单一的综合评价值(D值),客观、科学、准确地对参试的18份材料进行了综合评价,为甘蓝型油菜苗期耐湿性评价提供了方法参考。(3)15份创新种质除绿叶率外的9个测定指标的耐湿性系数均高于对照品种,耐湿性综合评价结果显示,15份创新种质的D值均高于渝黄2号,13份创新种质的D值高于综合抗耐性俱佳的中油821,3份创新种质的D值高于高耐湿品种中双9号,聚类得到的高耐湿类群的7份材料中创新种质占6份(85.71%)。可见,创新种质的耐湿性平均要优于对照品种,说明通过远缘杂交获得的创新种质对甘蓝型油菜的耐湿性有了较为明显的改良和提高。 相似文献
94.
Breeding bacterial blight-resistant hybrid rice with the cloned bacterial blight resistance gene Xa21 总被引:1,自引:0,他引:1
Zhai Wenxue Wang Wenming Zhou Yongli Li Xiaobing Zheng Xianwu Zhang Qi Wang Guoliang Zhu Lihuang 《Molecular breeding : new strategies in plant improvement》2002,8(4):285-293
The cloned bacterial blight (BB) resistance gene Xa21 was transferred into Minghui63, a widely used restorer line of indica hybrid rice in China, through an Agrobacterium-mediated system. Molecular and resistance analyses revealed that the Xa21 gene was integrated in the genomes of transgenic plants and their progeny inherited resistance stably. For the purpose of hybrid breeding, Xa21 transgenic homozygous restorer lines were selected through `within-lane' dosage comparison of hybridization signal in combination with PCR and resistance analyses. The selected transgenic restorer lines were then crossed with a commonly used sterile line, Zhenshan97A, to produce Xa21 transgenic hybrid rice, Shanyou63-Xa21. The hybrid rice plants with Xa21 displayed high broad-spectrum resistance to Xanthomonas oryzae pv. oryzae (Xoo) races and maintained elite agronomic characters of Shanyou63. The propagation of this BB-resistant hybrid variety with Xa21 will benefit rice production. 相似文献
95.
普通小麦"济南177"(Triticum aestivum L.cv.Jinan177)经继代培养和选择,形成了性质不同的愈伤组织,一种生长迅速,易于形成悬浮系,游离的原生质具有旺盛的分裂能力,但不能分化,称为Cha9;另一种具有一定能力,但游离原生质体分裂能力低,称为176.二者之一来源的原生质体与紫外线照射的青苗碱谷原生质体融合均不能获得再生植株.而将源于Cha9和176的两种原生质体混合,与经紫外线照射的青苗碱谷原生质体在PEG诱导下融合,融合产物再生了大量植株.再生的愈伤组织及植株经表现型、细胞学、有工酶、RAPD分析,证明了其杂种性质,用不麦叶绿体特异的简单得复序列(SSR)引物分析了再生杂种的叶绿体遗传组成情况.在不同的杂种克隆中,同时带有Cha9和176的遗传物质并含有供体核及胞质基因组的克隆4具有较高的分化能力,再生了大量生长旺盛的完整植株. 相似文献
96.
Zechner U Shi W Hemberger M Himmelbauer H Otto S Orth A Kalscheuer V Fischer U Elango R Reis A Vogel W Ropers H Rüschendorf F Fundele R 《Journal of evolutionary biology》2004,17(2):453-460
Interspecific hybridization in the rodent genera Peromyscus and Mus results in abnormal placentation. In the Peromyscus interspecies hybrids, abnormal allelic interaction between an X-linked locus and the imprinted paternally expressed Peg3 locus was shown to cause the placental defects. In addition, loss-of-imprinting (LOI) of Peg3 was positively correlated with increased placental size. As in extreme cases this placental dysplasia constitutes a post-zygotic barrier against interspecies hybridization, this finding was the first direct proof that imprinted genes may be important in speciation and thus in evolution. In the Mus interspecies hybrids, a strong role of an X-linked locus in placental dysplasia has also been detected. However, here we show by backcross and allele specific expression analyses that neither LOI of Peg3 nor abnormal interactions between Peg3 and an X-linked locus are involved in generating placental dysplasia in Mus hybrids, although the placental phenotypes observed in the two genera seem to be identical. In contrast to this, another dysgenesis effect common to Peromyscus and Mus hybrids, altered foetal growth, is caused at least in part by the same X-chromosomal regions in both genera. These findings first underline the strong involvement of the X-chromosome in the genetics of speciation. Secondly, they indicate that disruption of epigenetic states, such as LOI, at specific loci may be involved in hybrid dysgenesis effects in one group, but not in another. Thus, we conclude that even in closely related groups divergent molecular mechanisms may be involved in the production of phenotypically similar post-zygotic barriers against hybridization. 相似文献
97.
A hybrid anaerobic solid-liquid (HASL) bioreactor is an enhanced two-phase anaerobic system, that consists of a solid waste reactor as the acidification reactor and a wastewater reactor, i.e. an upflow anaerobic sludge blanket (UASB) reactor as the methanogenic reactor. Food waste digestion in HASL bioreactors with pre-acidification and HASL operation stages was investigated in two separate runs. After 8 days of pre-acidification in Run A and 4 days in Run B, total volatile fatty acid (TVFA) and chemical oxygen demand (COD) concentrations in the leachates of both acidification reactors were similar. During HASL operation stage, TVFA and COD removal in the methanogenic phase were 77–100% and 75–95%, respectively. Some 99% of the total methane generated was from the methanogenic phase with a content of 68–70% methane. At the end of operation, about 59–60% of the added volatile solids (VS) were removed with a methane yield of 0.25 l g–1 VS. 相似文献
98.
小麦条锈病是影响杂交小麦普及推广的重要因素。文章利用基因推导法和SSR分子标记技术,研究了温光型两系杂交小麦恢复系MR168的抗条锈性遗传规律及其控制基因染色体位置。结果表明,MR168对CY29、CY31、CY32、CY33等条锈菌生理小种表现高抗至免疫;对SY95-71/MR168杂交组合的正反交F1、BC1、F2和F3群体分单株接种鉴定显示,MR168对CY32号小种的抗性受1对显性核基因控制,该抗病基因来源于春小麦品种辽春10号。利用集群分离分析法(Bulked segregant analysis,BSA)和简单重复序列(Simple sequence repeat,SSR)分子标记分析抗病亲本MR168、感病亲本SY95-71及183个F2代单株,发现了与MR168抗条锈病基因连锁的5个微卫星标记Xgwm273、Xgwm18、Xbarc187、Xwmc269、Xwmc406,并将该基因初步定位在1BS着丝粒附近,暂命名为YrMR168;构建了包含YrMR168的SSR标记遗传图谱,距离YrMR168最近的两个微卫星位点是Xgwm18和Xbarc187,遗传距离分别为1.9 cM和2.4 cM,这两个微卫星标记可用于杂交小麦抗条锈病分子标记辅助育种。 相似文献
99.
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 相似文献
100.
以小麦(Triticum aestivum L.)与高冰草(Agropyron elongatum(Host)Nevski)体细胞杂种同一个克隆来源的F2-F6自交系Ⅱ-2、Ⅱ-Ⅰ-8以及由Ⅱ-Ⅰ-8 F2分离形成的8-1(F3-F6)为材料,利用小麦叶绿体基因组的微卫星(Microsatellite)特异引物及随机扩增多态性DNA(RAPD)引物进行分析.结果表明,杂种株系的叶绿体基因组组成一致,均以小麦叶绿体基因组为主,仅在rpl14和rpl16基因的间隔序列中检测到双亲的特征带,表明有高冰草的叶绿体DNA在杂种中存在,并稳定遗传至第六代.RAPD分析表明,不同杂种株系中存在不同的高冰草核DNA片段,核基因组在传代中基本稳定. 相似文献