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51.
Tomosaburo Yabuno 《Euphytica》1987,36(2):529-534
Summary It is shown that the restorer gene Rf
j
extracted from the Japanese rice variety Akebono is effective on pollen restoration in the cytoplasm substitution line having the nucleus of Oryza glaberrima and japonica or indica cytoplasm of O. sativa, and is of the sporophytic type.The Asian perennial type of the wild rice species O. rufipogon is considered to be the progenitor of O. sativa. Two substitution lines having the cytoplasm of a perennial strain of O. rufipogon from Sri Lanka and the nucleus of O. glaberrima with or without the gene Rf
j
in homozygous condition have been bred by means of successive backcrosses. These lines have now reached the BC5 generation. Plants of the lines resemble morphologically the recurrent parent, but do not show pollen restoration, indicating that the cytoplasm of the rufipogon strain induced male sterility and that the gene Rf
j
does not act as the restorer. 相似文献
52.
Summary The group 1 and 6 inter-varietal chromosome substitution lines of Cappelle-Desprez (Bezostaya 1) were intercrossed along with the donor and recipient varieties, Cappelle-Desprez and Bezostaya 1, to give 36 genetically different families. The analysis of the means of these families showed that variation in SDS-sedimentation volume fitted a predominantly additive model. There were no significant within or between chromosome interactions among the group 1 and 6 chromosomes. Nor was there any evidence for interactions between these chromosomes and those of the background. Significant dominance/within chromosome interactions amongst the background chromosomes were however detected. Some of the positive effects on SDS-sedimentation were associated with increased grain hardness. Chromosome effects on % grain protein were not correlated with SDS-sedimentation. 相似文献
53.
Among the wheatgrasses that are possible sources of genetic resistance for wheat to barley yellow-dwarf-virus disease (BYD) are those that have been commonly subsumed under the name Agropyron elongatum (Host) P. Beauv. Two of these wheatgrass species are the diploid Lophopymm elongatum (Host) Á. Löve (2n = 2x = 14) and the decaploid L. ponticum (Podp.) Á. Löve (2n = 10x = 70). These two species, the addition and substitution lines of L. elongatum chromosomes in hexaploid wheat (Triticum aestivum L.), and derivatives of hybrids between hexaploid wheat and L. ponticum, were screened for resistance to BYD, as defined by visual symptoms in field-grown plants. The two species, an amphiploid derived from L. elongatumבChinese Spring’ wheat, and the derivatives involving L. ponticum chromosomes were all highly resistant. The substitution and addition lines of L. elongatum chromosomes in ‘Chinese Spring’ revealed that the genetic control of resistance in L. elongatum must be complex, with more than one critical locus involved. Chromosomes 2E and 5E are involved and there are lesser contributions to resistance from the remaining wheatgrass chromosomes. One highly resistant derivative was determined to have only three pairs of L. ponticum chromosomes. It has a wheat-like morphology and shows promise for further characterization. 相似文献
54.
Tomosaburo Yabuno 《Euphytica》1981,30(3):867-873
Summary In common rice, Oryza sativa L. (n=12), the gene Am for non-glutinous is dominant over the gene am for glutinous. In African rice, O. glaberrima Steud. (n=12), no spontaneous glutinous strain has been found, but recently a glutinous strain of glaberrima was induced by EMS-treatment.The interspecific cytoplasm substitution line with sativa cytoplasm and glaberrima nucleus is male sterile. It has been confirmed that the complete restoration of pollen fertility in this male sterile line is attributed to a single dominant nuclear gene Rf
j.Trial to transfer gene am from sativa to glaberrima was commenced with backcrosses of the F1 hybrid (glutinous sativa cv. Iwai-mochi × glaberrima ) to glaberrima type plants of the substitution line homozygous for Rf
j,using the latter as the pollen parent. At the B1 step, highly fertile glaberrima type Am/am plants were obtained. Thereafter plants of this type were backcrossed to normal glaberrima as the recurrent pollen parent to complete the nuclear substitution. It was confirmed that the EMS-induced glutinous character of glaberrima was a monogenic recessive and that the same gene controls the expression of glutinous character in the different rice species, sativa and glaberrima. 相似文献
55.
Hikmet Budak P. Stephen Baenziger Brian S. Beecher Robert A. Graybosch Benjamin T. Campbell Marry J. Shipman Mustafa Erayman Kent M. Eskridge 《Euphytica》2004,137(2):261-270
Hexaploid triticale (X Triticosecale Wittmack) (2n= 6x= 42, AABBRR) and wheat (Triticum aestivum L.) (2n= 6x= 42, AABBDD) differ in their R and D-genomes. This produces differences in both agronomic and end-use quality characteristics. Our objective was to determine how introgressions of individual chromosomes from the D-genome of wheat affect these characteristics of a winter triticale 'Presto'. We studied the effects of 18 D-genome chromosome substitution lines, 15 sib-lines as controls, and five check cultivars at Lincoln, NE in 1996, using a randomized complete block design with two replications. The experiment was repeated at Lincoln and Mead, NE in 1997 and 1998 with 15 substitution lines that survived the first winter in Lincoln, along with their 12 control sibs and five check cultivars. Few D-genome chromosomes had positive effects. Chromosomes 2D, 4D, and 6D significantly reduced plant height when substituted for 2R, 4B, and 6R, respectively. No grain yield increases were associated with any of the D-genome chromosomes tested, but three substitutions decreased the grain yield. Depending on the allele of the hardness gene present, chromosome 5D increased or decreased kernel hardness when substituted for 5R or 5A, respectively. Introgressions of chromosomes 1D and 6D improved end-use quality characteristics of Presto. These results suggest that apart from beneficial effects of individual loci located on the D-genome chromosomes, no major benefit can be expected from D-genome chromosome substitutions. 相似文献
56.
利用分子标记、细胞学、基因组原位杂交(GISH)等技术,结合田间农艺性状调查,对小麦–华山新麦草七倍体材料H8911与硬粒小麦D4286杂交F4代分离群体中株系DH2322进行了综合鉴定。华山新麦草基因组特异SCAR标记鉴定表明,DH2322含有华山新麦草遗传物质;细胞遗传学观察显示,DH2322染色体构型为2n=42=21 II;有丝分裂和花粉母细胞减数分裂中期I基因组原位杂交(GISH)鉴定表明,DH2322的染色体由40条小麦染色体和2条华山新麦草Ns染色体构成,且2条Ns染色体能完全配对为一个二价体;SSR和STS分子标记分析表明,DH2322缺失小麦D基因组的2D染色体,而含有华山新麦草的2Ns染色体;农艺性状分析结果表明,DH2322具有双亲的形态学特征,结实性好,穗长和穗粒数显著大于亲本。 相似文献
57.
Fine mapping of the genetic locus L1 conferring black pods using a chromosome segment substitution line population of soybean 下载免费PDF全文
Qingyuan He Hongyan Yang Shihua Xiang Dong Tian Wubin Wang Tuanjie Zhao Junyi Gai 《Plant Breeding》2015,134(4):437-445
The colour of plant organs is a useful trait in crop breeding. The pod colours of soybeans primarily include black, brown and tan types, which are controlled by two classical genetic loci, L1 and L2. Most wild soybeans have black pods, which reflect a possible role in adaptation to the natural environment. Here, an improved chromosome segment substitution line (CSSL) population SojaCSSLP3 was established to identify the L1 gene. The segment on the 19th chromosome represented by the SSR marker Satt313 was found to link with locus L1. The region was further delimited three times with increased SSR and InDel markers using a population derived from a heterozygous plant of CSSL124 from SojaCSSLP3. The L1 gene was finally located in a 184.43‐kb region between SSR_19p09 and Indel_19P7. Thirteen putative genes in this region were analysed with qRT‐PCR. The expression level of Glyma19 g27460, which is a member of the SANT superfamily with a MYB DNA‐binding domain, was significantly upregulated in black pods and was recognized to be the most likely candidate for the L1 gene. 相似文献
58.
Zhi-Shan Lin Zhi-Fu Cui Xiang-Yan Zeng You-Zhi Ma Zeng-Yan Zhang Toshiki Nakamura Goro Ishikawa Kazuhiro Nakamura Hisashi Yoshida Zhi-Yong Xin 《Euphytica》2007,158(1-2):109-118
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat-Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that
line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452
were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was
a double ditelosomic line with the mitotic chromosome number of 2n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain
terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably
2Ai-2S telosomes with BYDV-resistance. These wheat-Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines. 相似文献
59.
Adam J. Lukaszewski 《Euphytica》1997,94(3):257-261
Complete chromosomes 1R and 1B were reconstructed in wheat from the centric wheat-rye translocation 1RS.1BL. Three substitutions:
1R(1A), 1R(1B), 1R(1D), and three new centric translocations: 1RS.1AL, 1RS.1BL, 1RS.1DL were produced from the reconstructed
chromosome 1R. Each one of these has the same rye chromosome arm 1RS which was present in the original translocation 1RS.1BL
of ‘Kavkaz’ wheat. Reconstructed chromosome 1B and a normal chromosome 1R were used to produce a new 1RS.1BL translocation.
This translocation has the long arm from the original 1RS.1BL translocation of ‘Kavkaz’, but a different 1RS arm. The third
generation centric translocations were mitotically stable and were normally transmitted to progeny. Misdivision frequency
of the reconstructed chromosomes 1R did not change relative to normal 1R, whereas the misdivision frequency of the two reconstructed
chromosomes 1B tested was significantly higher relative to normal 1B. These experiments demonstrate that repeated cycles of
centric breakage and fusion do not impair the function of centromeres in wheat and rye but may change chromosome's susceptibility
to misdivision.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
60.
Fluorescence in situ hybridization (FISH) with a genome‐specific repeat, Spelt1, and wheat simple sequence repeat (SSR) markers were used to analyse the chromosome constitution of two Triticum aestivum×Aegilops speltoides introgressive lines. The lines 170/98i and 178/98i carried one and two subtelomeric regions of Ae. speltoides (per haploid genome), respectively, marked by Spelt1 repeats according to FISH data. SSR analysis detected homoeologous substitution of wheat chromosome 7D with Ae. speltoides chromosome 7S in the lines 178/98i and 170/98i as well as the assumed terminal translocation in the short arm of chromosome 3A in the line 178/98i. Anthocyanin pigmentation of the coleoptiles was found in the lines 170/98i and 178/98i and resulted from the 7S (7D) substitution. It was demonstrated that Spelt1 could be effectively used for the rapid identification (without DNA isolation) of terminal translocations of T. aestivum×Ae. speltoides introgressive lines as well as for further analysis of the stability of the hybrid plants. 相似文献