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41.
《Communications in Soil Science and Plant Analysis》2012,43(12):1423-1436
Abstract From a field experiment in which wheat was supplied with nitrogen fertilizer at 0, 20, 40, 60, 80, 100, 150, 200, or 400 kg ha‐1N, a correlation existed between nitrate concentration in wheat stems at tillering and subsequent grain yield. At early tillering, NO3‐N concentrations around 8,000 μg g‐1 were indicative of sufficient nitrogen in the crop‐soil system for maximum grain yield. Averaging the results of this experiment with those from another seven field experiments, it was concluded that at tillering, the prognostic levels of NO3‐N concentration in stems were: below 4000 μg g‐1 deficient, between 4000 and 6000 μg g‐1 intermediate, between 6000 and 10000 μg g‐1 sufficient and above 10000 excessive for maximum grain yield. These values are applicable in a wide range of water supply conditions and to a number of cereal genotypes. 相似文献
42.
The importance of hybrid rye (Secale cereale L.) breeding has steadily increased over the last decades. This paper presents results of model calculations aiming to optimize the number of candidates, testers to assess combining ability and test locations at each selection stage of a standard scheme of seed‐parent line development. Two variants of the scheme differing in the number of stages and the cycle length are investigated. Optimization criterion is the expected selection gain per year under the restriction of a fixed budget. Prediction of selection gain rests on quantitative–genetic and economic parameters estimated from breeders’ data. Optimization covers different genetical and economical situations. Results show that the optimum number of testers to assess combining ability depends on the relative amount of dominance variance. The efficiency of a breeding scheme strongly increases with decreasing cycle length. A larger budget should mainly be used to increase the number of candidates at all selection stages. Recommendations for practical breeding schemes are given. We conclude that model calculations are a valuable tool for the optimization of breeding schemes. 相似文献
43.
小麦EST-SSR标记的开发和染色体定位及其在追踪黑麦染色体中的应用 总被引:7,自引:1,他引:6
根据小麦盐胁迫诱导和茎秆组织相关EST序列开发了81对EST-SSR引物, 其中67、46、18和61对分别在小麦、黑麦、簇毛麦和大麦基因组中稳定扩增, 在不同小麦和大麦品种间具有多态性的引物分别有22和23对。利用小麦缺体-四体系共定位了43对引物的81个位点, 其中A、B和D染色体组上分别有29、30和22个位点, 涉及除4B、3D和6D外的18条染色体。此外30对引物在黑麦基因组中具有特异扩增, 其中8对分别在黑麦1R、4R、5R和R7染色体上具有特异扩增, 7对在多条黑麦染色体具有相同扩增。这些新标记可有效用于小麦及其近缘物种的遗传作图与比较遗传研究。 相似文献
44.
Isolation of a new repetitive DNA sequence from Secale africanum enables targeting of Secale chromatin in wheat background 总被引:1,自引:0,他引:1
Cheng Liu Zu-Jun Yang Guang-Rong Li Zi-Xian Zeng Yong Zhang Jian-Ping Zhou Zhao-Hui Liu Zheng-Long Ren 《Euphytica》2008,159(1-2):249-258
A genome specific DNA sequence that detects Secale africanum chromatin incorporated into wheat was developed in this study. Random amplified polymorphic DNA (RAPD) analysis was used
to search for genome specific DNA sequences of S. africanum in lines, R111, “mianyang11” (MY11) and wheat-rye 1RS/1BL translocations R25 and R57. A high copy rye-specific DNA segment
pSaD15940 of the S. africanum genome was obtained. The sequence of pSaD15 did not show any significant homology to other reported sequences in databases
and it is therefore a new repetitive sequence of Secale. PCR primers were designed for pSaD15940, which amplify a clear 887 bp fragment in S. africanum but not in any wheat. The primers also amplified an 887 bp fragment in other accessions of rye, Chinese Spring-Imperial rye
chromosome additions and a diverse range of material carrying different rye chromosomes or chromosomal segments. In situ hybridization
showed that probe pSaD15940 was specifically hybridized throughout all rye chromosomes arms except for the terminal regions. The advantage of the rye-specific
probe developed herein compared to those of previous reports is that it has been shown to be widely applicable to other Secale species. The probe will be useful as a molecular marker for the introgression of S. africanum and other rye chromosome segments into the wheat genome. 相似文献
45.
Elzbieta G Magnucka Yoshikatsu Suzuki Stanislaw J Pietr Arkadiusz Kozubek Robert Zarnowski 《Pest management science》2009,65(10):1065-1070
BACKGROUND: Cycloate inhibits the biosynthesis of very‐long‐chain fatty acids, the essential constituents of plant waxes and suberin. Fatty acids also serve as precursors of aliphatic carbon chains in resorcinolic lipids, which play a fundamental role in the plant defence system against fungal pathogens. In this study, the effect of cycloate on the biosynthesis of 5‐n‐alkylresorcinols in rye seedlings (Secale cereale L.) grown under various light and thermal conditions was examined. RESULTS: The content of alkylresorcinols biosynthesised in rye was generally increased by the herbicide in both green and etiolated plants. The presence of cycloate also affected patterns of alkylresorcinol homologues in plants grown at 15 and 22 °C; very‐long‐side‐chain compounds were less abundant, whereas both short‐chain saturated and unsaturated homologues were generally accumulated. No cycloate‐related effects caused by homologue pattern modifications were observed at elevated temperature. CONCLUSION: This study extends present understanding of the mode of action of thiocarbamate herbicides. Cycloate markedly affected the biosynthesis of very‐long‐side‐chain resorcinolic lipids in rye seedlings, confirming the existence of parallels in both fatty acid and alkylresorcinol biosynthetic pathways. The observed cycloate‐driven accumulation of 5‐n‐alkylresorcinols may improve the resistance of cereals to infections caused by microbial pathogens. Copyright © 2009 Society of Chemical Industry 相似文献
46.
Annual rye grass ( Lolium multiflorum Lam.) is a serious and wide spread problem in cereal crops. A field experiment with a promising herbicide diclofop [(±)-2-[4-(2,4-dichlorophenoxy)phenoxy] propanoic acid] at 0.56, 0.84 and 1.12 kg ai/ha, in comparison to commonly used linuron [ N' -(3,4-dichlorophenyl)- N -methoxy- N -methylurea] at 0.84, 1.12 and 1.41 kg ai/ha was conducted to control rye grass ( Lolium multiflorum Lam.) in triticale (X Triticosecale Wittmack), wheat ( Triticum aestivum L.) and rye ( Secale cereale L.). The herbicides were applied as soil-incorporated, preemergence and post-emergence. Results showed that diclofop is less phytotoxic than Linuron and the postemergence application of these herbicides was more phytotoxic on all cereal crops. Diclofop applied at 1.12 kg/ha, gave almost 100 percent rye grass control and produced 45 and 115 kg/ha higher grain yields in pre- and postemergence methods, respectively, as compared to the soil-incorporated method. 相似文献
47.
Pollen Longevity in Wheat, Rye and Triticale 总被引:4,自引:0,他引:4
The duration of pollen life was measured for several varieties of wheat, rye and triticale to determine whether the inclusion of alleles for pollen longevity from alien sources would be necessary and effective in hybrid wheat production. Percent seed set was calculated from spikes in which emasculated flowers had been pollinated with pollen stored for specified time intervals under desiccation and under normal greenhouse conditions. Seed was set on wheat, rye and triticale lines using pollen stored for 45, 220, and 80 minutes, respectively. These results indicate that the duration of wheat pollen life is adequate for fertilization to occur under conditions normally used in hybrid wheat production, and that. Introgression of alien alleles is not necessary. 相似文献
48.
人工合成的双二倍体在遗传和植物育种中有重要作用。为探讨远缘杂交后代双二倍体育性提高及其细胞学稳定的分子机制,利用ALFP、MASP技术对节节麦-黑麦杂种及其双二倍体S1~S4代的基因组变异进行了分析。该双二倍的S1~S4代体细胞染色体数2n = 28的植株的比例从57.1%提高到92.5%,2n = 28的植株的花粉母细胞减数分裂中期二价体平均数目从11.7提高到12.25,平均结实率从24.5%提高到51.3%。利用两套分别扩增重复序列和单拷贝序列的酶切引物组合EcoR I/Mse I (E-M)、Pst I/Mse I (P-M)对节节麦–黑麦杂种F1和双二倍体S1~S4代扩增表明,基因组序列变异主要发生于F1代,且以序列消除为主。E-M和P-M引物扩增带中, 节节麦基因组在F1代的序列消除带数占各代总消失带数的70.00%和52.95%,而在黑麦基因组为96.88%和81.64%。MSAP分析表明节节麦和黑麦杂种和加倍能够导致节节麦和黑麦基因组序列甲基化状态改变,以甲基化为主,仅发生在F1和S1代。在S2~S4代中没有检测到甲基化变异。 相似文献
49.
冬牧70黑麦+箭舌豌豆混播草地生物量,品质及种间竞争的动态研究 总被引:19,自引:1,他引:18
作者在位于华北农牧交错的承德地区鱼儿山牧场中国农业大学科技蔟关试验站,对冬牧790黑麦和箭舌豌豆单播及混播的一年生人工草地进行了生物量动态,牧草品质及种间竞争的研究。结果表明,冬牧70黑麦单播最佳刈割期为抽穗期,混播的最刈割期为黑麦乳熟早期,箭舌豌豆下部呈荚充满时间。最佳的混播组合为冬牧70黑麦25%+箭舌豌豆75%和冬牧70黑麦50%+。从整个混播群落看,冬牧70黑麦生长快,植株高,其竞争力强于 相似文献
50.