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31.
Two disomic barley chromosome addition lines and five translocated chromosome addition lines of common wheat cultivar Shinchunaga
were isolated. They were derived from a hybrid plant between Shinchunaga and cultivated barley Nyugoruden (New Golden) by
backcrossing with wheat and self pollination. Barley chromosomes added to chromosome arms involved in the translocated chromosomes
were identified by C-banding method and by crossing these lines with Chinese Spring/Betzes addition lines. Two disomic addition
lines were identified to have chromosome 6 and 7 of barley, respectively. Two of the five translocated chromosome addition
lines were clarified to have same chromosome constitution, 42 wheat chromosomes and a pair of translocated chromosomes constituted
with a long arm of chromosome 5B of wheat and a short arm of chromosome 7 of barley. The other three lines could not be identified
due to chromosome rearrangement. Performances of these seven lines on agronomic characters were examined. Addition of barley
chromosome 7 induced early heading, and chromosome 6 showed lated heading. Almost all of the lines except that of chromosome
6 showed short culm length and all showed reduced number of tillers, spikelets and grains per ear, and low seed fertility.
These lines would be useful for genetic analyses in wheat and barley and for induction of useful genes of barley into wheat.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
32.
大麦幼胚培养再生植株及其后代的细胞遗传学研究 总被引:3,自引:0,他引:3
从5个普通大麦品种的幼胚培养中均得到体细胞再分化植株。对214棵再生植株进行了细胞学检查,发现四倍体5株,占总数的2.3%;相互易位杂合体1株,占总数的0.46%。四倍体植株虽然得到少数大而瘪的种子,但它们次年没有发芽;易位杂合体减数分裂时的染色体构型为5Ⅱ+1Ⅳ,属于两对非同源染色体间的简单易位。其余所有二倍体植株的细胞 相似文献
33.
氮肥对杂交小麦果聚糖积累与转运及其杂种优势的影响 总被引:1,自引:0,他引:1
氮肥影响作物的碳氮代谢及生长发育。选用6个杂交小麦及其7个亲本材料在施氮(200 kg /hm2)和不施氮(0 kg /hm2)条件下,比较研究了不同生育期不同器官果聚糖的积累与转运及其杂种优势。无论施氮与否茎鞘和总麦草中果聚糖的积累模式基本相似。茎鞘是贮存果聚糖的主要营养器官,分配了总麦草果聚糖积累量的63%~87%,并在开花期其积累量达最大值。总麦草转运的85%以上的果聚糖来源于茎鞘,其对籽粒产量的贡献率最大(9.42%~19.36%)。氮缺乏减少叶片中果聚糖的积累量,但增加茎鞘和总麦草中果聚糖的积累量。穗轴及颖壳、茎鞘和总麦草的果聚糖积累在挑旗期、抽穗期和开花期存在一定的杂种优势(4.7%~51.7%),叶片、茎鞘和总麦草的果聚糖转运量、转运率也具有较强的杂种优势,施氮增强叶片中果聚糖的转运优势,但减弱茎鞘和总麦草中的转运优势。结果说明,杂交品种比其亲本具有更强的果聚糖转运能力,施氮对茎鞘果聚糖的积累与转运及其杂种优势均有抑制作用。 相似文献
34.
The use of anther culture in breeding winter wheat. II. Production of new doubled haploid lines of winter wheat with 1AL—1RS-translocation A total of 4472 anhers was cultured from 8 F1 populations of winter wheat with the 1AL—1RS wheat-rye translocation cultivar ‘Amigo’ as one of the crossing arents. When averaged over all populations a frequency of embruoid formation of 10% and of regeneration efficiency of green plants of 1% were observed. In addition to the 45 green regenerated plants, 93 albinos were obtained. 44% of the green plantlets had 21 chromosome in root tips and 29% were spontaneous diploids. Multiple peroxidases were used a biochemical markers in the subsequent characterization of the homogeneous breeding material. The electrophoretic patterns showed that 16 doubled haploids without rye chromosome segments were produced. In addition the features of dh0- plants showed, that several of the new 1AL—1RS-translocation lines were awnless. 相似文献
35.
P. Monneveux M. P. Reynolds J. González Aguilar R. P. Singh W. E. Weber 《Plant Breeding》2003,122(5):379-384
The 7DL.7Ag translocation from Lophopyrum elongatum that carries Lr19, a leaf rust resistance gene, was found to be associated with a significant increase in grain yield under irrigated, disease‐free conditions, but a generally lower yield under moisture stress conditions. These studies, however, involved a limited number of genetic recipients and environments, and the effect of the translocation on physiological traits was not considered. We examined the translocation effect in six different recipient genotypes and under five environmental conditions, including drought and heat stress. The increase in grain yield under irrigated conditions was associated with a higher rate of biomass production in the 7DL.7Ag lines and may be attributed to higher sink strength. Effect of the translocation on physiological traits was noted only under heat stress and was not associated with difference in yield. Under moisture stress conditions, 7DL.7Ag lines yielded less than their corresponding recipients, possibly because of a longer growing cycle. It is concluded that the effect of the 7DL. 7Ag translocation may very much depend on the phenological adaptation of the recipient genotype and the translocation may be useful for enhancing yield, mainly under favourable conditions. 相似文献
36.
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
37.
38.
根际是养分进入作物系统的门户,也是土壤-根系-微生物相互作用的微域。根际界面过程决定了氮磷养分的供应强度和有效性,最终影响了氮磷养分的利用效率和作物生产力。近年来,国内外在揭示农田土壤-根系-微生物系统中不同界面的养分转化、吸收和运输机制方面取得了一些新进展。在不同时空尺度上分析了影响土壤氮磷转化微生物组成的影响因子;研究了丛枝菌根系统形成的信号机制及其对氮磷吸收的基因调控机制;从信号网络、根系质子分泌和根构型的角度系统揭示了作物根系应对根际环境氮磷养分供应的形态和生理响应机制。未来针对根际氮磷高效利用问题,需要深入研究土壤-根系-微生物不同界面的协同机制和调控原理,在根际微域和土壤团聚体尺度开展微生物食物网及其关键功能微生物分布格局和演替规律的研究;揭示根构型对根系–微生物协同结构和功能的影响,研究养分缺乏条件下根内质子分泌和关键转运蛋白对根系生长和养分吸收的调控机制;针对粮食作物,研究根系-微生物对话中已知信号物质(如独脚金内酯和N-酰基高丝氨酸内酯)和新的信号物质(小RNA)的网络作用机制及其对多养分协同代谢的影响;最后,针对不同气候、土壤、作物类型区,提出提高氮磷利用效率的根际生物调控途径和措施。 相似文献
39.
Summary The occurrence of chromosomal interchanges was studied in F1 hyrids in two diallel schemes, including nine accessions of Triticum aestivum subsp. spelta, originating from Iran, Europe and North Africa, and the common wheat variety Chinese Spring as a reference. Seven accessions of subsp. spelta differed in one translocation from Chinese Spring. The European accession Grey differed in one or perhaps two interchanges from the reference variety, and Iran 417a showed a difference of three interchanges with Chinese Spring. In total six or perhaps seven interchanges were observed. Thus the number of translocation events in subsp. spelta appeared to be low. One translocation was unique and occurred only in the accession from North Africa. Also one accession from Europe, the landrace Schwarzwald, possibly carried a unique translocation. In both diallels an interchange with a relatively low coefficient of multivalent realisation at first meiotic metaphase was observed in most accessions. The two extra translocations in Iran 417a are considered to be the result of more recent translocation events, whereas the possible second translocation in accession Grey showed such a low coefficient of multivalent realisation that its existence could be doubted. 相似文献
40.
Shahbaz Khan Hafeez ur Rehman Muhammad Ashfaq Wahid Muhammad Farrukh Saleem Mumtaz Akhtar Cheema Shahzad Maqsood Ahmed Basra 《Journal of plant nutrition》2016,39(12):1681-1687
The impact of soil (1, 2 kg ha?1) and foliar (100, 200 mg L?1) boron (B) with control (no B) was evaluated on phenology and yield formation of Camelina each applied at stem elongation and flowering stages. Foliar (200 mg L?1) or soil B (2 kg ha?1) resulted in earlier flowering and maturity, increased fruit bearing branches (19.68%), number of siliqua, seeds per siliqua (4.6%), biological yield (15%), seed yield (24%), harvest index (11.4%) and oil contents (23%) than no B. Increased fruit bearing branches, seed filled siliqua or seed numbers, harvest index and oil quality can be attributed to changes in dry matter accumulated of stem with simultaneous increase in siliqua dry weight with foliar or soil applied B. In crux, foliar (200 mg L?1) or soil applied (2 kg ha?1) B seems promising to improve seed and oil yield, harvest index of Camelina sativa under B deficient condition. 相似文献