Characterization of T.aestivum-H.californicum chromosome addition lines DA2H and MA5H

In order to transfer useful genes of Hordeum californicum into common wheat （Triticum aestivum L.）, the T. aestivum c.v. Chinese Spring （CS）-H. californicum amphiploid was crossed to CS, and its backcrossing and self-fertilized progenies were analyzed by morpho- logical observation, cytological, biochemical and molecular marker techniques. Alien addition lines with two H. californicum chromo- somes were identified and their genetic constitution was characterized. STS-PCR analysis using chromosome 2B specific markers indi- cated that chromosome H3 of H. californicum belongs to homoeologous group 2, and was thus designated 2H. SDS-PAGE showed that chromosome H2 of H. californicum belongs to homoeologous group 5, and was designated 5H. The CS-H. californicum amphiploid and the chromosome addition lines （DA2H and MA5H） identified were evaluated for powdery mildew （Erysiphe graminis f. sp. triticii） resis- tance in field. The preliminary results indicated that the amphiploid showed higher powdery mildew resistance than CS. However, chro- mosome addition lines DA2H and MA5H were highly susceptible to powdery mildew, indicating that major powdery mildew resistant genes of H. californicum should be located on chromosomes other than 2H and 5H.

Monosomic Addition Lines of Flowering Chinese Cabbage(B.campestris L.ssp.chinensis var.parachinensis L.H.Bailey)-Chinese Kale(B.oleracea L.var.alboglabra L.H.Bailey)

Interspecific alien addition lines have played significant roles in gene mapping, intergenomic gene transfer and chromosomal homoeological identification between closely related species. Selection of alien addition lines was conducted by karyotype analysis and morphological observation with the reference of parents. Triploid interspecies hybrid （AAC, 2n = 3x = 29） was obtained from Brassica campestris ssp. chinensis var. parachinensis Qinglu 9601 （tetraploid, AAAA, 2n = 4x = 40） x B. oleracea var. alboglabra Baihua 9705 （diploid, CC, 2n = 2x = 18） by immature hybrid embryo culture in vitro. Five different alien monosomic addition lines （AA ＋ C2, AA ＋ C3, AA ＋ C4, AA ＋ C6, AA ＋ C7） were obtained from the backcross progenies of AAC x AA. Each alien monosomic addition line has some specific morphological characters. It is feasible to obtain alien addition lines from the progenies of AAC × AA by karyotype analysis and morphological observation based on the reference of parents

Identification of Molecular Markers for the Thinopyrum intermedium Chromosome 2Ai-2 with Resistance to Barley Yellow Dwarf Virus

The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridization (GISH) was used to analyze the chromosome constitution of Z1,Z2 by using genomic DNA probes from Th. intermedium and Pseudoroegneria strigosa . The results showed that the chromosome constitution of either Z1 or Z2 composes of 42 wheat chromosomes and two Th. intermedium chromosomes (2Ai_2). The 2Ai_2 chromosome is St_E intercalary translocation, in which the E genomic chromosome segment translocated into the middle region of the long arm of chromosome belonging to St genome. With the genomic DNA probe of Ps. strigosa , the GISH pattern specific to the 2Ai_2 chromosome may be used as a molecular cytogenetic marker. A detailed RFLP analysis on Z1, Z2 and their parents was carried out by using 12 probes on the wheat group 2 chromosomes. Twenty RFLP markers specific to the 2Ai_2 chromosome were identified. Two RAPD markers of OPR16 -350 and OPH09 -1580 , specific to the 2Ai_2 chromosome, were identified from 280 RAPD primers. These molecular markers could be used to assisted_select translocation lines with small segment of the 2Ai_2 chromosome and provide tools to localize the BYDV resistance.

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.

Progress on Transferring Elite Genes from Non-AA Genome Wild Rice into Oryza sativa through Interspecific Hybridization

The progress of research on transferring elite genes from non-AA genome wild rice into Oryza sativa through interspecific hybridization are in three respects, that is, breeding monosomic alien addition lines （MAALs）, constructing introgression lines （ILs） and analyzing the heredity of the characters and mapping the related genes. There are serious reproductive barriers, mainly incrossability and hybrid sterility, in the interspecific hybridization of O. sativa with non-AA genome wild rice. These are the ＇bottleneck＇ for transferring elite genes from wild rice to O. sativa. Combining traditional crossing method with biotechnique is a reliable way to overcome the reproductive barriers and to improve the utilizing efficiency of non-AA genome wild rice.

THE DEVELOPMENT OF MINOR-CALIBER COMPOSITE PIPES ON CORROSIVE WEAR-RESISTANT

The ceramic lined pipes had been produced by gravitational separation SHS method and influential factors on combustion synthesis was investigated.The experimental results showed that the ceramic lined pipes had been produced easily under condition that selecting pipes well distributed on the wall thickness ,proper preheating temperature and appropriate additive.

Molecular Cytogenetic Characterization of Wheat-Thinopyrum elongatum Addition,Substitution and Translocation Lines with a Novel Source of Resistance to Wheat Fusarium Head Blight

Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study, a series of wheat （cv. Chinese Spring, CS） substitution and ditelosomic lines, including Th. elongatum additions, were assessed for Type II resistance to FHB. Results indicated that the lines containing chromosome 7E of Th. elongatum gave a high level of resistance to FHB, wherein the infection did not spread beyond the inoculated floret. Furthermore, it was determined that the novel resistance gene（s） of 7E was located on the short-ann （7ES） based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm. On the other hand, Th. elongatum chromosomes 5E and 6E likely contain gene（s） for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines. Genomic in situ hybridization （GISH） analysis revealed that the alien chromosomes in the addition and substitution lines were intact, and the lines did not contain discernible genomic aberrations. GISH and multicolor-GISH analyses were further performed on three trans- location lines that also showed high levels of resistance to FHB. Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th. elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E, while line TA3493 was found to contain one pair of wheat-Th, elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat. Thus, this study has established that the short-arm of chromosome 7E of Th. elongatum harbors gene（s） highly resistant to the spreading of FHB, and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance, implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.

Characterization of Three Novel Wheat LThinopyrum intermedium Addition Lines with Novel Storage Protein Subunits and Resistance to Both Powdery Mildew and Stripe Rust

Wide hybridization is an effective approach for enhancing the resistance of bread wheat （Triticum aestivum L.） to biotic and abiotic stresses by introducing favorable alien genes （Sepsi et al., 2008）. Wheatgrass, Thinopyrum intermedium （Host） Barkworth ＆ D.R. Dewey or Agropyron intermedium （Host） Beauvoir （2n = 42; genome formula JJjSjSstst）, is a perennial species in the tribe Triticeae and an important source of wheat improvement for biotic and abiotic stress resistance and quality-related traits, such as high grain protein concentration （Chen et al., 1998; 2001; 2003; Han et al., 2004; Li and Wang, 2009）. In addition, the ready crossing ability of wheatgrass with various Triticum species has made it popular in germ- plasm development.

Establishment and characterization of new wheat-Thinopyrum ponticum addition and translocation lines with resistance to Ug99 races

Ug99, also designated as TFKSK, is a race of Puccinia graminis Pers.：Pers f. sp. tn＇tici Eriks. and E. Henn （Pgt） with broad virulence to wheat. It is the first known Pgt race possessing virulence to Sr31, a stem rust resistance （Sr） gene deployed in wheat varieties world- wide （Singh et al., 2011 ）. Since the first detection of TFKSK in 1998, a total of 13 Ug99 variants have been identified in several African countries.

Glucosinolates in Self-crossed Progenies of Monosomic Cabbage Alien Addition Lines in Chinese Cabbage

Brassica species have been reported to possess cancer preventive activity due to glucosinolates(GLS) and their derived properties. Many studies on GLS have focused on Brassica oleracea and Brassica rapa. However, information on GLS in progeny between Chinese cabbage(B. rapa ssp. pekinensis) and cabbage(B. oleracea var. capitata) remains limited. In this study, eight GLS were detected in the self-crossed progenies of monosomic cabbage alien addition lines in Chinese cabbage(Chinese cabbage–cabbage MAALs) and parental Chinese cabbage, and nine GLS were detected in the parental cabbage. The variation of GLS content ranges was greater in the progeny than in the parental Chinese cabbage. The nine GLS identified were subjected to PCA to evaluate the differences among progeny and parents. Eight progeny samples had a comprehensive principal component score closer to or greater than that of cabbage, and four of them exhibited glucoraphanin(GRA) and total GLS contents greater than that of Chinese cabbage with the relative content of total indolic GLS was greater than 50%. These results offered new opportunity to improve GLS-containing of Chinese cabbage using genes from cabbage.

Alteration of Terminal Heterochromatin and Chromosome Rearrangements in Derivatives of Wheat-Rye Hybrids

Wheat-rye addition and substitution lines and their self progenies revealed variations in telomeric heterochromatin and centromeres, Furthermore, a mitotically unstable dicentric chromosome and stable multicentric chromosomes were observed in the progeny of a Chinese Spring-lmperial rye 3R addition line. An unstable multicentric chromosome was found in the progeny of a 6R/6D substitution line. Drastic variation of terminal heterochromatin including movement and disappearance of terminal heterochromatin occurred in the progeny of wheat- rye addition line 3R, and the 5RS ditelosomic addition line. Highly stable minichromosomes were observed in the progeny ofa monosomic 4R addition line, a ditelosomic 5RS addition line and a 6R/6D substitution line. Minichromosomes, with and without the FISH signals for telomeric DNA （TTTAGGG）n, derived from a monosomic 4R addition line are stable and transmissible to the next generation. The results indicated that centromeres and terminal heterochromatin can be profoundly altered in wheat-rye hybrid derivatives.

Variation of wheatgrass chromosomes in wheat-wheatgrass alien addition line"TAI-27"revealed by fluorescence in situ hybridization(FISH)

The karyotype of the primary wheat wheatgrass alien addition line TAI 27 was 2 n=44 in which all of the chromosomes were metacentric and submetacentric.However,in the progeny of TAI 27 a pair of chromosomes had become small chromosomes in the two morphologically different plants.Fluorescence in situ hybridization(FISH)technique was used to analyze the two different plants.The observations indicate that a pair of small chromosomes in one variation line are from wheatgrass.In another variation line,a pair of small chromosomes are also from wheatgrass,while another pair of wheatgrass chromosomes have substituted the wheat chromosomes.TAI 27 and its variant lines showed a high level of resistance to barley yellow dwarf virus(BYDV).The possible explanation for such a variation and the potential use of the variant lines were discussed briefly.

Effects on Genome Constitution and Novel Cell Wall Formation Caused by the Addition of 5RS Rye Chromosome to Common Wheat

The cytological instability of common wheat-rye addition lines was investigated in the present study. The chromosome numbers of almost all addition lines were considerably stable, but those of CS ＋ 5R were very variable. The rye chromosome added in this line was found to be much shorter than expected. Fluorescent in situ hybridization with 5S rDNA and the centromere-speciflc probes clearly revealed that the short rye chromosome contains only a short arm of chromosome 5R （5RS）. In this line, chromosome numbers of both 5RS and common wheat were changeable. The chromosome numbers ranged from 2n = 36 to 2n = 44 in the cells carrying two 5RS, and ranged from 2n = 31 to 2n = 44 in one 5RS cells. In addition to the chromosome instability, the muIticells wrapped in a sac-like structure were frequently observed in the root meristematic tissues of CS ＋5RS after the enzyme treatment for chromosome preparation. Genomic in situ hybridization with rye DNA as a probe showed that all cells in sacs investigated were at the interphase stage and contained one or two 5RS chromosomes. An electron microscopic analysis revealed that the cells of CS＋5RS, particularly in sacs, have abnormal （irregular and curved） cell walls. These results indicate that 5RS has （a） specific factor（s） influencing the cell wall development as well as the genome stability.