Genetic determination of wheat resistance against <Emphasis Type="Italic">Puccinia graminis</Emphasis> (f. sp. <Emphasis Type="Italic">Tritici</Emphasis>) derived from <Emphasis Type="Italic">Aegilops cylindrica,Triticum erebuni</Emphasis>, and amphidiploid 4

Lines of winter soft wheat with introgressed new and effective Sr genes were developed as a result of interspecies hybridization at the Plant Breeding and Genetics Institute. The 85/06 line possesses the SrAc1 gene; the 47/06, 54/06, 82/06, 85/06, 87/06, 238/06, and 367/06 lines carry the SrAc1 and SrAc2 genes originated from Aegilops cylindrica; the 352/06 line has the SrTe1 and SrTe2 genes from Triticum erebuni; and the 12/86-04 line contains the SrAd1 and SrAd2 genes from Amphidipoid 4 (Triticum dicoccoides × Triticum tauschii).     

Natural or induced nucleocytoplasmic heterogeneity in Triticum longissimum.

Alien cytoplasms produce a variety of phenotypes in durum wheat (Triticum turgidum) and common wheat (Triticum aestivum) cultivars, which indicate the prevalence of cytoplasmic variability in the subtribe Triticinae. Intraspecific cytoplasmic differences have been demonstrated between the subspecies of Triticum speltoides, Triticum dichasians, and Triticum comosum. In this study, durum wheat lines with cytoplasm from two accessions, B and C, of Triticum longissimum were compared, and meiotic chromosome pairing between the group 4 homoeologues from the same two accessions was examined in common wheat. First, monosomic addition or monosomic substitution lines of common wheat with cytoplasm and one chromosome (designated B) from accession B were crossed with those having cytoplasm and a chromosome designated C-1 or C-2 from accession C. In each substitution line, an alien chromosome substituted for a group 4 homoeologue. Each alien chromosome had a "selfish" (Sf) gene, which remained fixed in the wheat nucleus. The F1s had greatly reduced meiotic pairing between chromosomes B and C-1 and B and C-2, which indicated greatly reduced homology between the group 4 homoeologues from the two accessions. Second, by using Triticum timopheevii as a bridging species, chromosome B in a common wheat line was eliminated and an euploid durum line with cytoplasm from accession B was obtained. This line was fertile. In contrast, a similarly produced durum line with cytoplasm from accession C was male sterile and retained a species cytoplasm specific (scs) nuclear gene from T. timopheevii. In conclusion, nuclear and cytoplasmic heterogeneity pre-existed between accessions B and C and they represent varieties or incipient subspecies in T. longissimum. Alternatively, the Sf genes produced chromosomal heterogeneity and mutated cytoplasmic genes from one or both accessions. Key words : meiotic drive, selfish gene (Sf), gametocidal gene (Gc), Triticum, Aegilops.     

利用基于PCR的分子标记区分普通小麦-提莫菲维小麦渐渗系

采用定位于小麦2B染色体上的72对分子标记对含小麦抗白粉病基因Pm6的8份普通小麦（T.aestivum L.）-提莫菲维（T.timopheevii zhuk.）渐渗系材料进行分析, 通过分子标记标图确定8份材料中渗入的提莫菲维小麦染色体片段的大小, 同时结合连锁图谱对这些材料进行了遗传和物理标图。参考本研究所用的分子标记在染色体2B上的定位结果, Pm6基因被位于2B 染色体长臂近末端2BL-6区域, 提莫菲维小麦2G染色体渐渗片断长度由短到长排列顺序为: IGV1-465相似文献   

Standard karyotype of Triticum longissimum and its cytogenetic relationship with T. aestivum.

C-banding polymorphism was analyzed in 17 accessions of Triticum longissimum from Israel and Jordan, and a generalized idiogram of this species was established. C-banding analysis was further used to identify two sets of disomic T. aestivum - T. longissimum chromosome addition lines and 13 ditelosomic addition lines and one monotelosomic (6S1L) addition line. C-banding was also used to identify T. aestivum - T. longissimum chromosome substitution and translocation lines. Two major nucleolus organizing regions (NORs) on 5S1 and 6S1 and one minor NOR on 1S1 were detected by in situ hybridization using a 18S-26S rDNA probe. Sporophytic and gametophytic compensation tests were used to determine the homoeologous relationships of T. longissimum chromosomes. The T. longissimum chromosomes compensate rather well and fertility was restored even in substitution lines involving wheat chromosomes 2A, 4B, and 6B that contain major fertility genes. Except for the deleterious gametocidal genes, T. longissimum can be considered as a suitable donor of useful genes for wheat improvement.     

不同细胞质的普通小麦"中国春"(Triticum aestivum var.Chinese Spring)与小偃麦杂交F1代的育性与减数分裂行为的研究

15个不同细胞质“中国春”小麦与八倍体小偃麦杂交 ,杂种F1减数分裂的染色体行为表明 :普通小麦与天蓝偃麦草的F或E组染色体之间存在着部分同源关系 ;D2 型细胞质促进部分同源染色体配对、但却抑制同源染色体配对 ;Sv 型细胞质对同源染色体或部分同源染色体的配对均有抑制作用 ;G型细胞质促进同源染色体配对。1 5个不同细胞质“中国春”小麦与六倍体小偃麦杂交 ,F1结实率很低 ,减数分裂中期的染色体行为混乱 ,单价体过多 ,或许意味着在天蓝偃麦草 (Elytrigiain termedium)与长穗偃麦草 (E .elongatum)的E组染色体之间存在着很大差别。随着回交代数的增加 ,选出G型、D2 型、Mt 型、Mu 型等细胞质雄性不育的八倍体小偃麦品系 ,其中D2 型细胞质八倍体小偃麦具有光周期敏感性雄性不育的特征 ;G型细胞质“远中 3”育性正常 ,表明八倍体小偃麦“远中 3”的E组染色体中存在G型胞质的育性恢复基因。     

Genotypic variation in tetraploid wheat affecting homoeologous pairing in hybrids with Aegilops peregrina.

The Ph1 gene has long been considered the main factor responsible for the diploid-like meiotic behavior of polyploid wheat. This dominant gene, located on the long arm of chromosome 5B (5BL), suppresses pairing of homoeologous chromosomes in polyploid wheat and in their hybrids with related species. Here we report on the discovery of genotypic variation among tetraploid wheats in the control of homoeologous pairing. Compared with the level of homoeologous pairing in hybrids between Aegilops peregrina and the bread wheat cultivar Chinese Spring (CS), significantly higher levels of homoeologous pairing were obtained in hybrids between Ae. peregrina and CS substitution lines in which chromosome 5B of CS was replaced by either 5B of Triticum turgidum ssp. dicoccoides line 09 (TTD09) or 5G of Triticum timopheevii ssp. timopheevii line 01 (TIMO1). Similarly, a higher level of homoeologous pairing was found in the hybrid between Ae. peregrina and a substitution line of CS in which chromosome arm 5BL of line TTD140 substituted for 5BL of CS. It appears that the observed effect on the level of pairing is exerted by chromosome arm 5BL of T turgidum ssp. dicoccoides, most probably by an allele of Ph1. Searching for variation in the control of homoeologous pairing among lines of wild tetraploid wheat, either T turgidum ssp. dicoccoides or T timopheevii ssp. armeniacum, showed that hybrids between Ae. peregrina and lines of these two wild wheats exhibited three different levels of homoeologous pairing: low, low intermediate, and high intermediate. The low-intermediate and high-intermediate genotypes may possess weak alleles of Ph1. The three different T turgidum ssp. dicoccoides pairing genotypes were collected from different geographical regions in Israel, indicating that this trait may have an adaptive value. The availability of allelic variation at the Ph1 locus may facilitate the mapping, tagging, and eventually the isolation of this important gene.     

Characteristics of somatic cell hybrids (mouse x Chinese hamster) with a different ratio of chromosome sets from the parent species. II. Thymidine kinase activity]

The activity of thymidine kinase (TK) was studied in series of somatic cell hybrids between the mouse cell line 3T3-4E (TK-) and Chinese hamster cells M-15-1 (HGPRT-). Four groups of hybrid lines with different ratio of parental chromosome sets have been investigated: 1) three lines containing one hamster and one mouse chromosome set (1 hs+1 ms); 2) one line with 2 hs+1 ms; 3) one line containing 3 hs+1 ms and 4) one line containing 1 hs+2 ms. Mixtures of extracts from the parental cells were shown to possess the expected TK activity. The calculation of the activity per cell revealed that the 1 hs+1 ms and 2 hs+1 ms hybrid lines possessed about 50% of the initial hamster cell TK activity. The decreased TK activity in these hybrids might be due either to a loss of hamster chromosomes or to some inhibitory effect of mouse genome in cells with the studied ratio of parental sets. The enzyme activity in the 3 hs+1 ms hybrid was as expected, about three times greater than that of hamster cells.     

Development and molecular cytogenetic identification of new winter wheat--winter barley ('Martonvásári 9 kr1' - 'Igri') disomic addition lines.

This paper describes a series of winter wheat - winter barley disomic addition lines developed from hybrids between winter wheat line Triticum aestivum L. 'Martonvásári 9 kr1' and the German 2-rowed winter barley cultivar Hordeum vulgare L. 'Igri'. The barley chromosomes in a wheat background were identified from the fluorescent in situ hybridization (FISH) patterns obtained with various combinations of repetitive DNA probes: GAA-HvT01 and pTa71-HvT01. The disomic addition lines 2H, 3H, and 4H and the 1HS isochromosome were identified on the basis of a 2-colour FISH with the DNA probe pairs GAA-pAs1, GAA-HvT01, and pTa71-HvT01. Genomic in situ hybridization was used to confirm the presence of the barley chromosomes in the wheat genome. The identification of the barley chromosomes in the addition lines was further confirmed with simple-sequence repeat markers. The addition lines were also characterized morphologically.     

小麦耐盐种质的筛选鉴定和耐盐基因的标记

通过对 40 0份材料的芽期、苗期鉴定 ,筛选出 11份耐盐性较强的普通小麦 (TriticumaestivumL .)、小麦和黑麦 (SecalecerealeL .)、小麦和延安赖草 (Leymuschinensis (Trin .)Tzvel.)杂交后代材料 ,其中耐盐性突出的材料有 :普通小麦品种“红蚂蚱”、“科遗 2 6”、“希望”(Hope) ;小麦与黑麦杂交后代材料 98_46、98_113、98_131;小麦与延安赖草杂交后代材料 98_16 0、98_16 1、98_16 3。耐盐性表现最突出的材料是 98_113和 98_16 0。细胞学鉴定和原位杂交及醇溶蛋白酸性聚丙烯酰胺凝胶电泳 (A_PAGE)分析和低分子量谷蛋白SDS_PAGE分析 ,证明 98_113是稳定的小麦 黑麦二体附加系 ,但具体附加的是黑麦的哪条染色体还不清楚 ;98_131是小麦 黑麦 1B/ 1R易位系。结合其他 1B/ 1R材料的耐盐表现 ,提出了黑麦 1R染色体短臂上存在耐盐基因的可能性。对 (98_16 0×BanacakaMska)F2 代分离群体苗期抗盐鉴定分析 ,表明在这一杂交组合中的耐盐性状可能由一个主效基因控制。应用SSR标记技术 ,筛选到了与 98_16 0耐盐性状连锁的SSR标记WMS6 7和WMS2 13,它们与耐盐基因的遗传距离分别为 13.9cM (centMorgan)和 31.0cM。结合小麦SSR图谱分析 ,将该主效抗性基因定位在 5BL上。     

Regeneration of somatic hybrids in relation to the nuclear and cytoplasmic genomes of wheat and Setaria italica.

Somatic hybridization via PEG (Polyethylene 6000)-mediated protoplast fusion was achieved between two different wheat culture lines (Triticum aestivum L., "Jinan"177, T1 and T2) and Setaria italica (L.) P. Beauv. The T1 recipient originated from non-regenerable long-term cell suspensions, while T2 was derived from embryogenic calli with a high regeneration capacity. Donor protoplasts were obtained from embryogenic calli of S. italica (S) (with low regeneration capacity) irradiated with different doses of ultraviolet light. Twenty-three putative hybrid cell lines were produced in fusion combinations with the donor protoplasts treated with UV light for 30 s (combination I) and 1 min (combination II), but only one (from combination II) differentiated into green plants. Three cell lines from combination I and five cell lines from combination II possessed the nuclear genomes of T1, T2, and S. italica as revealed by cytological, isozyme, RAPD, and 5S rDNA spacer sequence analyses. Genomic in situ hybridization (GISH) analysis showed that most hybrid cell lines had 22-36 wheat chromosomes, 0-2 S. italica chromosomes, and 1-6 wheat - S. italica recombinant chromosomes, whereas the regenerable cell line had 44-56 wheat chromosomes and 3-6 recombinant chromosomes, but no intact S. italica chromosomes. RFLP analysis of organellar DNA revealed that mitochondrial and chloroplast DNA of both parents coexisted in all hybrid cell lines and recombined in most hybrid cell lines. These results indicate that the regeneration of hybrid plants involves not only the integration of S. italica nuclear and organellar DNA, but also the genome complementation of T1 and T2.     

<Emphasis Type="Italic">MlAG12</Emphasis>: a <Emphasis Type="Italic">Triticum timopheevii</Emphasis>-derived powdery mildew resistance gene in common wheat on chromosome 7AL

Wheat powdery mildew is an economically important disease in cool and humid environments. Powdery mildew causes yield losses as high as 48% through a reduction in tiller survival, kernels per head, and kernel size. Race-specific host resistance is the most consistent, environmentally friendly and, economical method of control. The wheat (Triticum aestivum L.) germplasm line NC06BGTAG12 possesses genetic resistance to powdery mildew introgressed from the AAGG tetraploid genome Triticum timopheevii subsp. armeniacum. Phenotypic evaluation of F₃ families derived from the cross NC06BGTAG12/‘Jagger’ and phenotypic evaluation of an F₂ population from the cross NC06BGTAG12/‘Saluda’ indicated that resistance to the ‘Yuma’ isolate of powdery mildew was controlled by a single dominant gene in NC06BGTAG12. Bulk segregant analysis (BSA) revealed simple sequence repeat (SSR) markers specific for chromosome 7AL segregating with the resistance gene. The SSR markers Xwmc273 and Xwmc346 mapped 8.3 cM distal and 6.6 cM proximal, respectively, in NC06BGTAG12/Jagger. The multiallelic Pm1 locus maps to this region of chromosome 7AL. No susceptible phenotypes were observed in an evaluation of 967 F₂ individuals in the cross NC06BGTAG12/‘Axminster’ (Pm1a) which indicated that the NC06BGTAG12 resistance gene was allelic or in close linkage with the Pm1 locus. A detached leaf test with ten differential powdery mildew isolates indicated the resistance in NC06BGTAG12 was different from all designated alleles at the Pm1 locus. Further linkage and allelism tests with five other temporarily designated genes in this very complex region will be required before giving a permanent designation to this gene. At this time the gene is given the temporary gene designation MlAG12.     

Comparative characteristic of Triticum aestivum/Triticum durum and Triticum aestivum/Triticum dicoccum hybrid lines by genomic composition and resistance to fungal diseases under different environmental conditions

The genetic diversity of common wheat hybrid lines Triticum aestivum/Triticum durum and Triticum aestivum/Triticum dicoccum (2n = 42, F_6–7) using chromosome-specific microsatellite (SSR) markers and C-banding of chromosomes was studied. Cluster analysis of data obtained by 42 SSR markers indicated that the hybrid lines can be broken into three groups according to their origin. There were two cases of complete genetic similarity between lines 183₂-2/184₁-6 and 208-3/213-1, which were obtained using common wheat as the parental plants. In cross combinations, when the stabilization of the nuclear genome of hexaploid lines occurred against a background of the cytoplasmic genome of tetraploid wheats, there was a high level of divergence between sister lines, in some cases exceeding 50%. The evaluation of the degree of susceptibility of the lines to powdery mildew, leaf and stem rust, and septoria leaf blotch was performed under different environmental conditions. It was shown that resistance to powdery mildew and leaf rust significantly depended on the region where assays were conducted. An evaluation of the field data showed that the lines 195-3, 196-1, and 221-1 with T. durum genetic material displayed complex resistance to fungal pathogens in Western Siberia and the Republic of Belarus. For lines 195-3 and 196-1, one shows a possible contribution of chromosomes 4B and 5B in the formation of complex resistance to diseases. Hybrid lines with complex resistance can be used to expand the genetic diversity of modern common wheat cultivars for genes of immunity.     

Introgression of Resistance to Powdery Mildew Conferred by Chromosome 2R by Crossing Wheat Nullisomic 2D with Rye

Using the nulUsomic back-cross procedure, four wheat-rye chromosome substitution 2R （2D） lines with different agronomic performance, designated WR02-145-1, WR01-145-2, WR02-145-3, and WR02-145-4, were produced from a cross between 2D nullisomic wheat （Triticum aestivum L. cv. ＂Xiaoyan 6＂） and rye （Secale cereale L. cv. ＂German White＂）. The chromosomal constitution of 2n=42=21 in WR02-145 lines was confirmed by cytological and molecular cytogenetic methods. Using genomic in situ hybridization on root tip chromosome preparations, a pair of intact rye chromosomes was detected in the WR02-145 lines. PCR using chromosome-specific primers confirmed the presence of 2R chromosomes of rye in these wheat-rye lines, indicating that WR02o145 lines are disomic chromosome substitution lines 2R （2D）. The WR02-145 lines are resistant to the powdery mildew （Erysiphe graminis DC. f. sp. tritici E. Marchal） isolates prevalent in northern China and may possess gene（s） for resistance to powdery mildew, which differ from the previously identified Pm7gene located on chromosome 2RL. The newly developed ＂Xiaoyan 6＂- ＂German White＂ 2R （2D） chromosome substitution lines are genetically stable, show desirable agronomic traits, and are expected to be useful in wheat improvement.     

普通小麦99-2439 中的白粉病抗性遗传

普通冬小麦品系99-2439在郑州连续4年对田间白粉菌(Blumeria graminis sp. tritici)表现高抗,但其抗性基因来源不清。通过染色体C-分带和1RS染色体特异性SCAR标记鉴定, 表明它是一个小麦-黑麦(Triticum aestivum - Secale cereale)1BL/1RS异易位系。通过对中国春×99-2439杂交F2代分离群 体抗性鉴定和1RS染色体臂检测结果分析, 证明该抗病基因不在1RS染色体臂上。用单孢小麦白粉菌分离株对其抗性遗传进行研究, 结果表明, 99-2439的白粉病抗性由一对小种专化、隐性抗病基因控制。由于携带Pm5a的Hope/8Cc对中国的21个小麦白粉菌分离菌株均高度感病, 而99-2439高抗混和白粉菌和5个单孢分离菌株, 所以, 99-2439所携带的抗白粉病基因不同于Pm5a。     

The detection of nonallelic to known genes of resistance to Tilletia caries (DC) Tul. in wheat strains from interspecific hybridization (Triticum aestivum x Aegilops cylindrica)

It was established by hybridological analysis that winter bread wheat lines 1/74-91, 3/36-91, 5/55-91 possess single dominant gene of resistance to bunt (Tilletia caries (DC) Tul.), but lines 8/2-91, 5/43-91, 4/11-91 and 8/16-91 have two independent dominant genes for this character. These genes originated from Aegilops cylindrica are not identical to Bt1-Bt17 genes and are unknown to date. The lines were obtained from crosses between winter bread wheat variety Odeskaya polukarlikovaya and Aegilops cylindrica.     

Recent advances in optical fiber devices for microfluidics integration

This paper examines the recent emergence of miniaturized optical fiber based sensing and actuating devices that have been successfully integrated into fluidic microchannels that are part of microfluidic and lab‐on‐chip systems. Fluidic microsystems possess the advantages of reduced sample volumes, faster and more sensitive biological assays, multi‐sample and parallel analysis, and are seen as the de facto bioanalytical platform of the future. This paper considers the cases where the optical fiber is not merely used as a simple light guide delivering light across a microchannel, but where the fiber itself is engineered to create a new sensor or tool for use within the environment of the fluidic microchannel.

Detection and trapping of molecules can be achieved with optical fibers directly located within the fluidic microchannel.     

普通小麦99-2439中的白粉病抗性遗传

普通冬小麦品系99-2439在郑州连续4年对田间白粉菌(Blumeria graminis sp.tritici)表现高抗,但其抗性基因来源不清.通过染色体C-分带和IRS染色体特异性SCAR标记鉴定,表明它是一个小麦-黑麦(Triticum aestivum-Secale cereale)lBL/1RS异易位系.通过对中国春×99-2439杂交F2代分离群体抗性鉴定和1RS染色体臂检测结果分析,证明该抗病基因不在1RS染色体臂上.用单孢小麦白粉菌分离株对其抗性遗传进行研究,结果表明,99-2439的白粉病抗性由一对小种专化、隐性抗病基因控制.由于携带Pm5a的Hope/8Cc对中国的21个小麦白粉菌分离菌株均高度感病,而99-2439高抗混和白粉菌和5个单孢分离菌株,所以,99-2439所携带的抗白粉病基因不同于Pm5a.     

Identification, mapping, and application of polymorphic DNA associated with resistance gene Pm21 of wheat.

A new powdery mildew resistance gene designated Pm21, from Haynaldia villosa, a relative of wheat, has been identified and incorporated into wheat through an alien translocation line. Cytogenetic and biochemical analyses showed that chromosome arms 6VS and 6AL were involved in this translocation. Random amplified polymorphic DNA (RAPD) analysis was performed on recipient wheat cultivar Yangmai 5, the translocation line, and H. villosa with 180 random primers. Eight of the 180 primers amplified polymorphic DNA in the translocation line, and the same results were obtained in four replications. Furthermore, RAPD analysis was reported for substitution line 6V, seven addition lines (1V-7V), and the F1, as well as F2 plants of (translocation line x 'Yangmai 5'), using two of the eight random primers. One RAPD marker, specific to chromosome arm 6VS, OPH17-1900, could be used as a molecular marker for the detection of gene Pm21 in breeding materials with powdery mildew resistance introduced from H. villosa. Key words : RAPD analysis, 6VS-specific marker, Pm21, Erysiphe graminis f.sp. tritici, Triticum aestivum - Haynaldia villosa translocation.     

Enhancement of somatic embryogenesis and plant regeneration in Japanese red pine (Pinus densiflora)

The highest proliferation rate (9.8-fold) of embryogenic suspensor mass (ESM) was obtained from half-strength Litvay (½LM, Litvay et al. 1985) medium supplemented with 3.42 mM l-glutamine, while the lowest rate was noted when 0.84 mM l-glutamine (0.6-fold) was added to the medium. The highest growth ratio with brassinolide (BL) was observed for 1.0 μM (2.3-fold, line 05-21) and 0.05 μM (2.9-fold, line 06-22). However, in the ESM lines 05-21 and 06-22, high ESM growth rates (2.3-fold, line 05-21 and 2.1-fold, line 06-3) were seen without BL when compared with 1.0 μM (05-21) or 0.05 μM (06-22). BL-supplemented medium has been shown to have diverse, genotype-specific effects on the degree of ESM proliferation. For somatic embryo maturation with 0.05 % activated charcoal (AC), the highest number (798 g^?1 FW) of cotyledonary somatic embryos (line 06-29) were obtained on a maturation medium supplemented with AC. The influence of light-emitting diode (LED) sources on the germination of somatic embryos (four genotypes) in this species was studied and was strongly genotype-dependent. Germination of somatic embryos from ESM line 05-3 was strongly inhibited by fluorescent, and red + blue light, while lines 05-12, 05-29, and 05-37 showed a similar germination frequency for the five LED sources, where red light most stimulated somatic embryo germination.     

Categories of resistance to greenbug (Homoptera: Aphididae) biotype K in wheat lines containing Aegilops tauschii genes

The wheat lines (cultivars) 'Largo', 'TAM110', 'KS89WGRC4', and 'KSU97-85-3' conferring resistance to greenbug, Schizaphis graminum (Rondani), biotypes E, I, and K were evaluated to determine the categories of resistance in each line to greenbug biotype K. Our results indicated that Largo, TAM110, KS89WGRC4, and KSU97-85-3 expressed both antibiosis and tolerance to biotype K. Largo, KS89WGRC4, and KSU97-85-3, which express antixenosis to biotype I, did not demonstrate antixenosis to biotype K. The results indicate that the same wheat lines may possess different categories of resistance to different greenbug biotypes. A new cage procedure for measuring greenbug intrinsic rate of increase (r(m)) was developed, by using both drinking straw and petri dish cages, to improve the efficiency and accuracy of r(m)-based antibiosis measurements.