Molecular Cloning and Characterization of a DFR from Developing Seeds of Blue-grained Wheat in Anthocyanin Biosynthetic Pathway

Blue-grained wheat derived from the hybrid Triticum aestivum L. X Thinopyrum ponticum (Podp.) Barkworth et D. R. Dewey (Agropyron elongatum (Host) P. Beauv., 2n=70). The molecular biological mechanism of the biosynthetic pathway of blue pigments in the blue grain remains unclear yet. Dihydroflavonol 4-reductase (DFR) is one of the key enzymes controlling flavonoid synthesis in anthocyanin biosynthetic pathway, and may directly participate in the formation of blue pigment in the aleurone layer of blue-grained wheat. Here we cloned a DFR cDNA (TaDFR) from the developing seeds of blue-grained wheat, and four DFR genomic DNAs from Th. ponticum (ThpDFR.t), blue-grained wheat (TaDFR.bg), white-grained offspring of light blue-grained wheat (TaDFR.wg) and Chinese Spring (2n=42) (TaDFR.csg), respectively. TaDFR cDNA encodes a 354 amino-acids polypeptide with high identity to DFR from Hordeum vulgare L. (94%), Oryza sativa L. (83%), Zea mays L.(84%). The result of cluster analysis showed that TaDFR cDNA nucleotide sequence has 100% identity with that of TaDFR.csg. The four DFR genomic DNAs have extraordinary high homology and each has three introns. The differences of the four DFR genomic DNAs mainly exist in introns. Southern blotting analysis showed that there are at least 3-5 DFR copies in wheat, the copy numbers in different color grain wheats are not significantly different. The hybridization band patterns were the same, but different from that of Th. ponticum. DFR in blue-grained wheat belongs to a DFR superfamily. Northern blotting analysis indicated that the DFR expressed in the developing seeds of both blue- and white-grained wheat at 15 d after flowering (DAF), the mRNA levels of DFR reached the highest at 18 DAF, then declined quickly and disappeared at 33 DAF But the expression levels in blue-grained seeds were higher than that in white grain at the same seed developing stages. DFR transcripts accumulated in young leaves, and leaf sheaths of blue- and white-grained wheat and Th ponticum, but not detected in roots from different color wheats and developing seeds of Th. ponticum. Results indicated that there may exist some regulatory gene(s) which can increase the expression of DFR in the aleurone layer of blue-grained wheat, and thus resulting in the formation of blue pigments.

Genetic Analysis of Monosomic Alien Addition Line MAAL8 of O. officinalis(CC)-O. sativa(AA)

[Objective] By carrying out the anther culture on the monosomic alien addition line MAAL8 of O.officinalis-O.sativa and the back crossing with O.sativa H1493,the genetic characteristics of monosomic alien addition line were studied.[Method] The phenotype analysis was used to study the separation proportion of progeny.Moreover,SSR and the methylation analysis were used to study the transmission behavior of nonhomologous chromosome.[Result] 78 plants of 145 backcross progenies preserved the rolled leaf mark trait of MAAL8.In 32 anther culture plants,five plants had the normal rolled leaves,and two plants had the extremely rolled leaves.The rest had the flat leaves.14 couples of SSR markers were used to analyze,and it indicated that all the rolled-leaf plants could obtain the characteristic band type of O.officinalis,but the flat-leaf plants showed none of them.11 polymorphic RFLP markers were used to carry out Methylation-Sensitive Southern analysis.It showed that the methylation variation manners of eight markers between AA and CC genomes were different.[Conclusion] The nonhomologous chromosome of MAAL8 could pass to the progenies independently and integrally via the meiosis,and the phenotype characteristics didn＇t change.Moreover,the methylation manner of O.officinalis could inherit stably in the hybrid progeny as the addition of single chromosome.The stability of methylation might have the certain effect on the relatively independent inheritance of nonhomologous chromosome in the genome environment of O.sativa.

Assignment of unanchored scaffolds in genome of Brassica napus by RNA-seq analysis in a complete set of Brassica rapa-Brassica oleracea monosomic addition lines

The economically valuable oil crop Brassica napus(AACC,2 n=38),which arose from interspecific hybridization between the diploid ancestors Brassica rapa(AA,2 n=20) and Brassica oleracea(CC,2 n=18),has a complex genome.More than 10% of the assembled sequences,most of which belong to the C subgenome,have not been anchored to the corresponding chromosome.Previously,a complete set of monosomic alien addition lines(MAALs,C1–C9) with each of the nine C-subgenome chromosomes added to the extracted A subgenome was obtained from the allotetraploid B.napus donor Oro,after the ancestral B.rapa(RBR Oro) genome was restored.These MAALs effectively reduced the complexity of the B.napus genome.Here,we determined the expression values of genes on unanchored scaffolds in the MAALs and RBR Oro.Then,multiple comparisons of these gene expression values were used to determine the affiliations of the nonanchored scaffolds on which the genes were located.In total,54.68%(44.11 Mb) of the 80.67 Mb of non-anchored scaffolds belonging to the C subgenome were assigned to corresponding C chromosomes.This work highlights the potential value of these MAALs in improving the genome quality of B.napus.

The Meiotic Behavior of an Alien Chromosome in Triticum aestivum-Haynaldia villosa Monosomic Addition Lines

By the combination of cytological analysis and using genomic in situ hybridization technique to identify an alien chromosome in wheat-Haynaldia villosa monosomic addition lines, we studied the meiotic behavior of the alien chromosome. The results indicated that the frequency of bivalent pairing was lower than the value expected in PMCs of two monosomic addition lines, the frequency of wheat chromosomes unpairing increased, and the wheat homologous chromosome pairing was interfered with by the added chromosome 6V at metaphase I. The chromosome 6V lagged in 20.3% -29.3% of PMCs, sister chromatids 6V early divided in 29.0% - 34.1% of PMCs, the single chromosome 6V in 18.2% - 26.1% of PMCs went to a pole randomly, the breakage frequency of chromosome 6V was 1.2% - 2.9%. Meanwhile, it was also found that several wheat chromosomes showed earlier division, lagging and breakage in a few PMCs. It revealed that the added chromosome 6V influenced the behavior of wheat chromosomes at anaphase. It was also found that the translo-cation was produced between 6V and wheat chromosomes in 1.2% of PMCs. It offered evidence for transloca-tion between wheat and Haynaldia villosa 6V chromosomes.

Morphological characteristics and identification of new monosomic stocks for cotton (Gossypium hirsutum L.)

The presence of distinct morphological markers in monosomics is important for selection and maintenance of the monosomic plants in subsequent generations and for a well-targeted chromosome substitutions. Here we present cytological and morphological features of the cotton (Gossypium hirsutum L.) monosomic lines developed in Uzbekistan, and their identification by means of translocation tests. We report “reduced” stigma as a new phenotypic marker for cotton monosomics, which makes it possible to distinguish cytotypes without cytological analyses. We identified eleven cotton monosomes by translocation tests using our 28 translocation cotton lines. We determined such features of the cotton monosomic lines as significant lowering of the pollen fertility, genetic determination of variation in pollen fertility in different flowers of the same monosomic plants and variation of both meiotic index and tetrads with micronuclei in different buds. New features of cotton monosomic lines, described herein, should be useful for future cotton genome investigation and development of new chromosome substitution lines.

Development of New Interspecific Monosomic F_1 Substitution Stocks for Investigations in Cotton Genome

As it is known a complete coverage of cotton(Gossypium hirsutum L.) genome with hypoaneuploids is not still realized.Therefore the detection of new types of aneuploids especially in different cytogenetic collections is very useful.In Uzbekistan,long-term investigations towards development

倾斜摄影三维建筑模型自动单体化与轮廓提取方法

针对当前倾斜摄影建筑物三维模型单体化和轮廓提取存在的问题和不足,提出一种对倾斜三维模型分层“切割”和基于多边形几何相似性判定的单体化及轮廓提取方法。该方法以倾斜摄影三维Mesh模型为对象,通过在不同的高程平面上对建筑物的三角格网进行投影、栅格二值化以及栅格-矢量转换等方法,提取建筑物的初始轮廓集,再采用一种多边形空间相似性判别的方法对轮廓集数据进行单体化计算和建筑轮廓提取,最后实现建筑模型的单体化渲染。研究表明,该方法具有不需要依赖第三方数据、自动化程度高、单体化和轮廓提取一体化的优点。该研究可以为当前城市级实景三维数据的实体化处理提供技术参考和方法选择。

重要抗源京核8811品系抗小麦条锈病主效基因的单体分析

采用单体分析技术 ,用中国小麦条锈菌优势小种 CY31和埃塞俄比亚菌系 35E134的单孢菌系对重要抗源京核 8811品系进行抗条锈基因分析及定位。结果表明 :京核 8811含有抗 35E134菌系、位于 2 A染色体上和抗 CY31菌系、位于 4 D染色体上的两对显性抗条锈基因 ,二者均控制 0 - 0 ;的侵染型。异同比较显示 ,定位基因不同于国际上已定名的抗条锈基因 ,谓之新基因 ,暂定名为 Yr Jh1和Yr Jh2。 Yr Jh2具有比 Yr Jh1更宽的抗性谱 ,二者同时存在 ,使京核 8811具有较强的抗条锈性 ,抗中国目前所有小种 。

小麦新材料“J-11”与黑麦可杂交性的遗传研究

新材料“J-11”比众所周知的高亲和性品系“中国春”具有明显更高的与黑麦的可杂交性。遗传分析表明,“J-11”与“中国春”的可杂交性基因一样表现为完全隐性。但控制“J-11”和“中国春”与黑麦可杂交性的基因型确实不尽相同。“J-11”除具有“中国春”的3对可杂交性基因,即5B上的kr_1、5A上的kr_(?)和5D上的kr_3外,还具有1个新的可杂交性基因kr_4,位子1A染色体上。新基因kr_4表现为强效,其效应比kr_1的弱,但比kr_2和kr_3的强。小麦可杂交性基因间存在互作,表现为纯合隐性等位基因对其它显性等位基因的抑制作用,而纯合隐性等位基因间的效应具有可加性。

小偃6号抗条锈性遗传分析

目的小偃6号是20世纪70年代末利用长穗偃麦草基因育成的著名品种,具有高温抗条锈性,研究其抗条锈遗传规律,对揭示其抗病机制和培育持久抗病品种具有重要意义。方法在常温[(10±1)℃～(16±1)℃]下,以小偃6号和铭贤169的杂交群体为研究对象,分析遗传规律,利用中国春单体对抗条锈基因进行染色体定位,利用SSR对抗条锈基因进行分子标记。测定所用菌种为Cy28和Cy29-mut3。结果小偃6号对CY28、CY29 mut-3的抗病性均由1对显性核基因控制。该抗条锈基因定位在4B染色体上。用4B上的11对SSR引物对该抗条锈基因进行了分子标记,找到了一个与小偃6号抗条锈基因紧密连锁的SSR标记Xgwm 107,这个标记位于4B染色体的长臂上,连锁分析表明其遗传距离为7.08cM。结论经典遗传学分析、单体分析、分子标记研究均支持将小偃6号的常温抗条锈基因定位于4BL上,这为进一步研究其高温抗病遗传和高温诱导抗病基因的调控表达奠定基础。

黄瓜单体异附加系的筛选与观察

将甜瓜属异源三倍体与栽培黄瓜‘北京截头’杂交,经胚胎拯救获得了两个2n:15(14C+1H)的单体异附加系,编号分别为02-17和02-39。02-17植株叶形为戟形,02-39为深陷的掌状形,并且果刺均为白色,不同于异源三倍体的掌状心脏形和黑刺,果形比异源三倍体黄瓜长而更接近普通黄瓜。细胞学研究发现,单体异附加系在终变期和中期I染色体构型主要是由7个二价体和1个单价体构成,出现三价体的频率为4％-5％,中期Ⅱ不均等分裂形成不同的两极,一极染色体为8条,另一极为7条。RAPD分析证明它们分别附加了野生种Cucumis hystrix的染色体。

染色体工程法聚合小麦优质麦谷蛋白亚基研究

采用小偃6号1D单体材料作为受体,中优6号、安农91168和皖38为5+10亚基的供体进行杂交,F1代田间苗期取根尖进行细胞学检测,孕穗期镜检花粉母细胞选择单体植株,并对其套袋自交.F2代籽粒在室内进行SDS-PAGE电泳筛选14+15和5+10亚基聚合且纯合籽粒,将5+10优质亚基转入当地主要优质源之一的小偃6号,同时将其聚合效率与正常二体杂交F2籽粒分离结果相比较.分析认为单体材料在亚基聚合中,其亚基分离完全符合一对基因的独立遗传,具有较高的选育效率.

小麦品种中梁22抗条锈病基因的遗传分析和分子作图

对中梁22/铭贤169杂交F2群体苗期抗条锈病鉴定及中国春单体系抗病基因的染色体定位发现,中梁22携带1个显性(暂命名YrZhong22)和1个隐性抗病基因,前者位于5B染色体。由中梁22×铭贤169的F2群体构建抗病、感病池,用SSR标记结合集群分离分析法(BSA),建立了与YrZhong22连锁的4个微卫星标记Xwmc289、Xwmc810、Xgdm116和Xbarc232,并将YrZhong22定位于小麦5BL染色体。YrZhong22与相邻微卫星位点Xwmc810和Xgdm116的遗传距离分别是2.7cM和4.4cM。系谱分析及分子标记分析表明,YrZhong22可能是一个来自中间偃麦草的新抗条锈病基因。

小麦品种“高优503”抗条锈基因染色体定位

本试验利用感染条锈病的“中国春”单体系列与抗条中 2 9号生理小种的“高优 50 3”小麦进行杂交 ,通过细胞学观察和田间锈病鉴定 ,对其抗病基因进行单体分析。结果表明 :“高优 50 3”小麦抗条中2 9号生理小种的基因位于 4 B和 5B染色体上 ,是两对显性基因。

小麦-簇毛麦单体异附加材料外源染色体减数分裂行为的研究

借助基因组原位杂交技术检测小麦 簇毛麦单体异附加材料中的外源染色体 ,并结合细胞学分析 ,追踪研究减数分裂期外源染色体的遗传行为。结果表明 ,在中期I ,2份单体异附加材料花粉母细胞 (PMCs)中的二价体配对频率比预期值低 ,出现了未配对的小麦单价染色体 ,附加的簇毛麦 6V染色体在一定程度上干扰小麦同源染色体的正常配对 ;在后期I ,2 0 .3%～ 2 9.3%PMCs中的 6V染色体落后 ,2 9.0 %～ 34.1%PMCs中的 6V姐妹染色单体提早分裂 ,18.2 %～ 2 6 .1%PMCs中的 6V染色体随机走向一极 ,6V染色体断裂的频率为 1.2 %～ 2 .9% ,同时有少量小麦染色体也发生了不规则分裂现象 ,表明附加的 6V染色体也影响小麦染色体后期的正常分离。另外 ,在减数分裂后期 ,观察到 1.2 %的PMCs中有簇毛麦 6V染色体和小麦染色体发生重组易位的现象。这为小麦与簇毛麦染色体间产生易位提供了依据。

陆地棉单体和端体细胞学行为与鉴定技术

报道了陆地棉单体和端体的细胞学鉴定时的染色体构型表现及其鉴定技术方法 ,并就陆地棉花粉母细胞减数分裂研究的取样。

小麦粒重基因定位研究

本文以低粒重的多小穗品系“10阿”为被测材料,“中国春”和“阿勃”两套单体系列为测验系,对粒重性状进行了基因定位研究。结果表明,被测材料“10阿”粒重低受5A、1B、2B、6B、2D和7D等染色体上的隐性基因所控制。从其减小效应的程度来看,1B和2B染色体上的基因表现为强效。5A、6B、2D和7D染色体上的基因表现为弱效。

普通小麦抽穗期基因定位的研究

本文以特晚熟多小穗品系10阿为被测材料,中国春和阿勃两套单体系列为测验系,对抽穗期性状进行了基因定位研究。结果表明,被测系10阿晚抽穗,受5A、1B、2B、6B和2D染色体上的隐性基因所控制。其中,2D染色体上的基因表现为强效,5A、1B、2B和6B染色体上的基因表现为弱效。据前人研究和本试验结果分析认为,被测系10阿的1B和2B染色体上可能具有控制晚熟性的新基因。

普通小麦多子房基因单体分析的染色体定位及双端体分析的染色体臂定位

本研究以普通小麦——“中国春”的单体系统和多子房小麦杂交,确定控制多子房性状的基因数目及关键染色体。通过单体分析,初步确定多子房性状分别受染色体5D和6B上的2个非互补的同效异位被动隐性基因所控制,分别用m_1和m_2表示。 继续用“中国春”双端体5DL、6BL和6BS分别与多子房进行正反交,在5DL、6BL与多子房的正反交F_1植株上均出现多子房表型。由此确定,控制多子房性状的m_1、m_2基因分别位于染色体5D和6B的短臂上(5DS、6BS)。

陆地棉单体的诱发及鉴定

本文报道了利用不同剂量的γ射线辐照陆地棉花粉诱导单体株的效率。未研究共鉴定分离出了Ａ染色体亚组中的第１、２、４ 染色体的单体以及Ｄ染色体亚组中的另１８染色体的单体，讨论了花粉辐照诱导陆地棉单体株的有效剂量；没有鉴定分离出新单体的原因。