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991.
Robin D. Graham 《Euphytica》1986,35(2):621-629
Summary Because copper is extremely important to the development of normal polllen, an attempt was made to induce male sterility in wheat by applying specific copper-binding ligands to wheat plants. Four different chelates were used at two rates in three methods of application. All four chelates, cupferron, neocuproine, benzotriazole and cuprizone, reduced grain yield at high concentration applied to the soil at sowing but benzotriazole was most effective, even when applied at late tillering to either soil or foliage, and it also reduced yield to a lesser extent when applied at low concentration. At high concentration of benzotriazole (50 mg kg-1 of dry soil) the percentage of pollen staining with I2/KI was very low (0–7%) depending on method of chelate application), and this soil treatment resulted in complete male sterility. The appearance of the pollen, anthers, grain, ears and leaves in many cases mimicked that of normal copper deficiency, and also that caused by other recognised gametocides. These results raise the question of whether binding of copper or some other disturbance of copper metabolism may be the mechanism by which andro-gametocidal chemicals work and if so, dictate a theoretical basis for selecting such chemicals for testing.  相似文献   
992.
A. C. Zeven 《Euphytica》1981,30(1):41-43
Summary It is shown that the near-isogenic line Michigan Amber/8*Chancellor cannot derive from Michigan Amber. Marquillo is suggested as the donor cultivar.  相似文献   
993.
Summary In a comparative study of reaction patterns and by analysis of segregation ratios in cross progenies, Triticum dicoccoides Koern. sel. G-25 was shown to possess a yet unknown gene for resistance to yellow rust. It is suggested to assign provisionally the symbol Yr15 to this gene.  相似文献   
994.
抽穗期是对普通小麦(Triticum aestivum L.)安全生产有重要影响的农艺性状,也是一个复杂的受多基因协调互作控制的性状。对普通小麦抽穗期基因控制系统、普通小麦抽穗期基因之一——Ta Hd1的克隆与功能、基因组定位、直向同源区微进化研究进展等方面进行了概述,以期为普通小麦抽穗期性状改良提供一定的理论参考。  相似文献   
995.
Summary A set of 21 monosomics of Novosadska Rana-1 was used to locate the rust resistance genes of Lüqiyu, a stripe rust resistant line developed by BAU and Yantar, a leaf rust resistant wheat introduced from Bulgaria. The resistance of the former to p. striiformis race C25 was conditioned by a dominant gene located on chromosome 2B, whereas that of the latter to P. recondita race CL3 was controlled by two complementary dominant genes located on chromosomes 5A and 1D, respectively. The relationship of the stripe rust resistance gene in Lüqiyu to Yr5, Yr7 or Yr Suwon' all located on chromosome 2B is unknown. The two complementary leaf rust resistance factors in Yantar appear to be new.  相似文献   
996.
L. Vapa  G. E. Hart 《Plant Breeding》1987,98(4):273-280
The zymogram phenotypes of 14 enzymes were determined for 80 Yugoslav wheat cultivars in order to identify probable allelic variants at structural gene loci. Enzyme phenotypes that differ from the one produced by Triticum aestivum cv.‘Chinese Spring’ were detected for six enzymes, namely, aromatic alcohol dehydrogenase-1, aconitase-1, amino peptidase-l, lipoxygenase-1, NADH dehydrogenase-1 and endopeptidase-1, and one or more probable allelic variants at the Aadb-B1, Aco-A1, Aca-B1, Amp-Al, Amp-B1, Ep-A1, Ep-B1, Lpx-A1, Lpx-B1 or Lpx-D1, and Ndh-B1 loci were identified.  相似文献   
997.
The male-sterile lines with Ms2 gene were highly evaluated in recurrent selection in wheat (Triticum aestivum L.). Three populations C6 (population after six cycles of selection), C7 (population after seven cycles of selection), and C8 (population after eight cycles of selection) were constructed through recurrent selection with 12 parental materials (P). Acid polyacrymide gel electrophoresis (A-PAGE) analysis was used to identify gliadin patterns and evaluate the genetic diversity in 12 parents and three populations. A total of 63 bands were identified, of which 17 polymorphic bands and 7 unique bands were present in populations and seven polymorphic bands and four unique bands were present in parents. The number of polymorphic and unique bands decreased gradually from C6 to C8, especially for to- and y-gliadins. The genetic distances in C6, C7, and C8 were calculated. The distributions of genetic distance were different in three recurrent selection populations. From C6 to C8, the genetic distance was 0.2687, 0.2652 and 0.1987, respectively. Statistically significant differences were detected between C7 and C8 with the T value of 37.9718. The result of cluster analysis based on genetic similarity matrix of three populations fitted well to those of principle coordinates analysis (PCoA). Compared with 12 parents, almost all individuals of three populations are new genotypes. Most of the individuals from C6 and C7 could be divided into two groups, while most individuals of C8 were in one cluster. In conclusion, the results indicated that the genetic diversity was decreased severely according to the information revealed by A-PAGE, although some variations could be created in the recurrent selection. It was necessary to introduce diverse germplasm based on the genetic database of recurrent population to maintain and improve the breeding efficiency in the further program.  相似文献   
998.
为给小麦品质性状的标记辅助选择提供备选分子标记,并进一步定位和克隆小麦部分品质相关性状的QTL,本研究利用普通小麦Heyne×Lakin杂交F2代单粒传获得的145个F8代重组自交系(Recombinantinbred line, RIL)群体,构建了含有2 082对标记(1 980对SNP标记和102对SSR标记)、总长度为2 120.13 cM的遗传连锁图谱,并利用该图谱对小麦连续两年的品质性状(蛋白质含量,湿面筋含量,淀粉含量和Zeleny沉降值)进行了 QTL分析。结果表明,共检测出11个QTL,其中,蛋白质含量有2个QTL,位于2A和5A染色体上,可解释的表型变异率6.94% 12.55%;湿面筋含量QTL有1个,位于5A染色体上,可解释的表型变异率8.40%~ 12.96%;淀粉含量QTL有3个,位于2A和5A染色体上,可解释的表型变异率9.78%~11.23%;Zeleny沉降值QTL有5个,位于2A、5A和7D染色体上,可解释的表型变异率4.75% 20.15%。其中5A染色体上存在这些品质性状QTL富集区,同时具有“一因多效”QTL位点。这个区段的发现,为小麦品质育种提供了参考依据。  相似文献   
999.
X. C. Zhao  P. J. Sharp   《Plant Breeding》1998,117(5):488-490
Null alleles of the three loci coding for ‘waxy’ proteins in bread wheat have been identified. Plants carrying different null alleles were collected and segregation of the null alleles in both selfed and doubled haploid progeny of plants simultaneously heterozygous for the null alleles at each of the three loci were examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Mendelian segregation of these alleles in both types of progeny was shown, indicating that they can easily be utilized in breeding programmes. Iodine staining of the eight possible null phenotypes showed that only the triple null type had zero amylose in its endosperm starch.  相似文献   
1000.
M. C. Luo  C. Yen  J. L. Yang 《Euphytica》1993,70(1-2):127-129
Summary The crossability percentages of 282 accessions of wheat (Triticum aestivum L.) collected in Tibet, China with rye (Secale cereale L.) have been tested. Five collections have a similar to and 277 accessions have a lower crossability percentage than Chinese Spring or are non-crossable with rye. The accessions with high crossability percentage occur along the highway near Lhasa. No landraces with higher crossability than Chinese Spring and rare landraces with similar crossability to Chinese Spring indicated that the landraces in Tibet region are different from those in Sichuan, Shaanxi and Henan provinces in the distribution frequency of high crossability, and there is no distribution of recessive kr4 alleles.  相似文献   
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