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杂交水稻不育系的配合力分析许旭明,余永安,张爱刚,黄显波,谢小丹(三明市农科所沙县365509)水稻不育系是水稻杂种优势利用的基础。70年代野败型不育系的选育成功,使我国杂交水稻实现了三系配套,至今珍汕97A、V20A仍然是杂交水稻生产上主要应用的不... 相似文献
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两系杂交水稻制种的安全性问题及其对策 总被引:3,自引:0,他引:3
我国两系杂交水稻在生产上已大面积推广应用,但由于两用核不育系只有在一定的温光生态条件下,其雄性不育基因才能表达,因而在实际的两系杂交水稻制种中存在着风险。综述了两系杂交水稻在制种过程中存在的安全性问题,提出了解决问题的技术策略及今后两系杂交水稻安全制种技术应重点研究解决的问题. 相似文献
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我国两系杂交水稻在生产上已大面积推广应用,但由于两用核不育系只有在一定的温光生态条件下,其雄性不育基因才能表达,因而在实际的两系杂交水稻制种中存在着风险.综述了两系杂交水稻在制种过程中存在的安全性问题,提出了解决问题的技术策略及今后两系杂交水稻安全制种技术应重点研究解决的问题. 相似文献
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水稻三系不同提纯方法浅析 总被引:2,自引:0,他引:2
水稻三系不同提纯方法浅析周天理,郑秀萍,张轼,张功宙(福建省农科院稻麦所福州350019)(福建省种子公司福州350003)林庆伟,苏容理(福建省大田县良种场)籼型杂交水稻是我国的一项在国内外具有重大意义的农业科技成果。1964年袁隆平首先提出了水稻... 相似文献
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杂交水稻三系不育系选育的实践与思考 总被引:18,自引:2,他引:18
回顾了杂交水稻三系不育系15 a来选育的实践,总结了选育杂交水稻三系不育系的经验与体会.1)利用籼粳交加花药培养快速稳定技术选育三系不育系及其保持系,育种难度大,成效低;2)选育优质不育系,低代品质鉴定是关键;3)不育系异交结实率的选择,应从柱头外露率和田间自然异交结实率两方面考虑;4)有针对性地进行个别性状的遗传改良选育新的不育系,可以达到事半功倍的效果;5)选育抗稻瘟病水稻不育系是非常必要的,应加强这方面的工作. 相似文献
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W. L. Porter 《American Journal of Potato Research》1967,44(10):382-382
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Effects of timing and rate of N fertilizer application on concentrations of P, K, S, Ca, Mg, Na, Cl, Mn, Fe, Cu and Zn in herbage from perennial ryegrass/white clover pastures were studied at two sites in south-western Victoria, Australia. Nitrogen fertilizer (0, 15, 25, 30, 45 and 60 kg ha–1 ) was applied as urea in mid-April, early May, mid-May, early June and mid-June 1996 to pastures grazed by dairy cows. At Site 1, N fertilizer resulted in a linear increase in P, K, S, Mg and Cl concentrations in herbage and a linear decrease in Ca concentration. For all times of application, concentrations of P, K, Ca, Mg and Cl in herbage increased by 0·0048, 0·08, −0·010, 0·0013 and 0·053 g kg–1 dry matter (DM) per kg N applied respectively. For S concentration, maximum responses occurred in mid-May (0·012 g kg–1 DM per kg N applied). At Site 2, N fertilizer resulted in a linear increase in P, S and Na concentrations in herbage, a linear decrease in Ca concentration and a curvilinear increase in K and Cl concentration. The maximum responses for P, S and K concentrations in herbage occurred for the N application in mid-June and were 0·015, 0·008 and 0·47 g kg–1 DM per kg N applied respectively. For Cl concentration, the maximum response occurred for the N application in early June and was 0·225 g kg–1 DM per kg N applied. Overall, applications of N fertilizer up to 60 kg ha–1 did not alter herbage mineral concentration to levels that might affect pasture growth or animal health. 相似文献
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Krishna Kumari S Thayumanavan B 《Plant foods for human nutrition (Dordrecht, Netherlands)》1998,53(1):47-56
Scanning electron microscope (SEM) pictures of small millet starch granules showed more large polygonal and few small spherical or polygonal granules. The granules of small millets resembled those of rice starch granules. The size of the starch granules ranged from 0.8–10 m. The size of the granules was larger in barnyard millet and smaller in proso millet. Several granules showed deep indentation caused by protein bodies. SEM of starch isolated from 24 hour-germinated kodo millet showed pitting or pinholes at some points due to the attack of amylases (preferentially on bigger granules). Brabender viscoamylograph studies on small millet starches revealed that the gelatinization temperatures ranged from 75.8 to 84.9 ° C. Barnyard millet possessed lower amylograph viscosity, minimum breakdown, and relative breakdown values when compared to the other small millets. 相似文献