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杂交水稻高产优质高效制种技术研究沈森和（龙岩农业学校）一、序言杂交水稻高产优质高效制种技术研究是杂交水稻生产中的一项重要科研新课题。三系法杂交水稻在制种技术研究上取得了突破性的进展，现已发展为超高产（高产、优质、带效）制种技术研究的新阶段。近年来，我... 相似文献
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对优质杂交籼稻丰优香占（粤丰A/R6547）及其亲本的特征特性和品质分析结果表明，丰优香占糙米率、长宽比、透明度、直链淀粉含量和碱消值接近双亲中值；整精米率明显高于双亲中值，偏向于高值亲本；垩白粒率、垩白度和胶稠度明显低于双亲中值，偏向于低值亲本；香味源自母本。针对杂交稻米垩白粒率高、垩白度大和胶稠度低的突出问题，提出优质杂交籼稻育种的关键是选育优质不育系和优质恢复系，特别是优质不育系的选育，通过广泛收集水稻种质资源，筛选理想材料作亲本，对现有不育系和恢复系进行遗传改良，优化组配，可达到培育优质杂交籼稻的目标。 相似文献
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杂交水稻品种改良的遗传基础和途径 总被引：3，自引：0，他引：3
阐述了杂交稻稻米品质的特点以及各品质性状的遗传特征，指出选育优质杂交组合必须以收集优质亲本资源为前提，并通过杂交选育、回交选育以及群体改良等手段加以改进，在创造出更为优良的亲本（不育系与恢复系）之后，采用优质亲本与中等或中等偏上米质的亲本配组，可以选育出适合广大群众所需要的普食型高产优质组合；采用优质亲本配优质亲本，可以选育出符合特殊消费和出口要求的高档优质组合。 相似文献
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通过试验，筛选出适应性广、抗逆性强、丰产性好的杂交玉米新品种，加快杂交玉米新品种的试验、示范、审定和推广步伐，促进丽江市杂交玉米生产向高产、优质、高效的方向发展，增加农民的经济效益。按照杂交玉米新品种区域试验项目实施方案要求，于2011年在丽江市永胜县永北镇金家村设置了杂交玉米区域试验。 相似文献
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杂交稻米及其亲本淀粉粒形态的扫描电镜观察 总被引：3，自引：2，他引：3
用扫描电镜观察了品质级别有显著差异的3个水稻不育系和3个恢复系及其所配的9个杂交组合共15个材料的胚乳淀粉粒。结果表明：不同品质的稻米均有其固定的淀粉粒形态。杂交稻米淀粉粒的形态因双亲米质的优劣而具有明显差异。双亲优质的杂交稻米，表现优质米淀粉粒形态；优质与中质杂交，表现中亲淀粉粒形态；优质与普通品质杂交，表现为超中亲淀粉粒形态；双亲均是普通品质者，表现质量超亲淀粉粒形态；中质与普通品质杂交，趋向高亲淀粉粒形态；双亲均是中质者，表现中质米淀粉粒形态。据此，淀粉的形态特征可作为鉴定稻米品质优劣的一个重要指标，又可为杂交稻品质育种从淀粉粒形态上选择亲本提供依据。 相似文献
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中国近25年来育成杂交籼稻组合的米质分析 总被引：4，自引：0，他引：4
为了解我国近25年来育成的杂交籼稻组合的米质状况和未来品质改良重点,分析了我国自1984年以来育成的4495份杂交籼稻组合的10项米质指标及其优质达标率。结果表明,检测的4495份杂交籼稻材料10项米质性状的优质达标率为34.2%～98.1%,平均78.5%。5项主要米质指标（整精米率、垩白度、透明度、直链淀粉含量和质量指数）全部达到优质标准的材料占29.9%。20世纪80年代、90年代和2001-2008年3个不同时期育成的杂交籼稻组合10项米质性状的平均优质达标率分别为64.2%、71.1%和81.4%,质量指数优质达标率分别为84.5%、86.4%和88.5%。2001-2008年期间育成的杂交籼稻材料5项主要米质指标全部达到优质标准的占32.9%,比20世纪80年代和90年代的分别高18.0和11.9个百分点,表明2001-2008年育成的杂交籼稻组合的米质总体优于20世纪80年代和90年代育成的组合。博优、中优和培优系列组合的米质较好。分析同时指出,我国杂交籼稻组合的垩白粒率和垩白度的优质达标率较低,仅34.2%和55.1%,是未来杂交籼稻米质改良的重点。 相似文献
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广西杂交早稻的现状和育种策略 总被引：10，自引：4，他引：10
从产量，米质和抗性等方面分析了广西目前生产上应用的杂交早稻组合的现状，认为优质化和多元化是杂交早稻的发展方向，以现有高产水平为基础，改良品质和抗性，选育适应市场的优质高产组合是广西“十五”杂交早稻育种攻关的重点。 相似文献
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论北方杂交粳稻的育种攻关 总被引：2，自引：0，他引：2
北方杂交粳稻的优势是显著的，对其育种攻关应持积极乐观的态度．对杂交粳稻生产上停滞滑坡的原因作了分析，在选育力量相对较弱和繁殖制种体系不健全的条件下，其推广利用的速度要求不能过急。从新组合高产、优质、多抗和易于制种的要求出发，在继续改良恢复系的同时，强调了矮秆、优质、抗病、配合力高、开花习性好的保持系的选育及不育系的转育。 相似文献
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F. W. Kirkham A. Bhogal B. J. Chambers R. M. Dunn J. R. B. Tallowin 《Grass and Forage Science》2013,68(2):260-270
The technique of enhancing species diversity by spreading species‐rich green hay following turf scarification was tested in a semi‐improved meadow site in Cumbria, UK. Botanical assessments were carried out in May 2008 (prior to treatment), May and October 2009, and May 2010. Both total species‐richness (number of species per m2) and the richness and aggregate cover of positive indicator species were enhanced by hay spreading, with an average of 21·8 species per m2 compared with 17·0–18·7 species per m2 for other treatments by May 2010. Significant increases in all three variables occurred by May 2009, with even greater increases between this assessment and May 2010. Hay spreading introduced seven new species, most of which subsequently increased over time, and enhanced the frequency of a further seven. All these species together accounted for only about 5% of vegetation cover in 2010, but the level of species‐richness achieved was equivalent to that of good quality semi‐improved grassland and also equivalent to that achieved in studies where the technique was developed. Results are discussed in detail in relation to the seeding phenology of species at the donor site, as are other factors affecting the technique's potential and possible means of enhancing it. 相似文献
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以播种面积集中度指数、波动指数为主要指标,对湖南近10年优质稻生产集聚与波动状况进行了研究.结果表明,全省播种面积的集中度指数、波动指数排序分别为优质晚稻＞优质早稻＞优质中稻及一季优质晚稻、优质中稻及一季优质晚稻＞优质晚稻＞优质早稻.明确了湖南优质稻播种面积稳定区、相对稳定区、波动区,并提出了湖南优质稻发展建议. 相似文献
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对通过四川省审定的13个川香29A所配三系杂交稻中籼迟熟组合的品质性状进行了分析,并研究了各品质性状间的相关关系。结果表明,13个组合的整精米率平均为58.5%,其中有12个组合达到国颁优质稻谷3级标准以上;长宽比平均为2.8,有5个组合达到国颁优质稻谷3级标准以上;垩白粒率平均为38.2%,有7个组合达到国颁优质稻谷3级标准以上;垩白度平均为7.6%,有6个组合达到国颁优质稻谷3级标准以上;胶稠度平均为63mm,有11个组合达到国颁优质稻谷3级标准以上;直链淀粉含量平均为22.4%,有9个组合达到国颁优质稻谷3级标准以上。在13个组合中只有3个组合的综合米质指标达国颁优质稻谷3级标准,制约综合米质达标的主要因子是长宽比、垩白度和垩白粒率。在各项品质指标中,长宽比与垩白粒率、垩白度呈极显著负相关;垩白粒率与垩白度呈极显著正相关;整精米率与垩白粒率呈显著负相关;直链淀粉含量与垩白粒率、垩白度呈显著正相关。因此,要进一步提升川香29A所配组合的稻米品质,应注重选用粒型细长、垩白粒率低和垩白度小的恢复系来进行配组。 相似文献
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Predicting anthesis date of perennial ryegrass (Lolium perenne L.) with growing degree‐days at heading 
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下载免费PDF全文 The agronomic significance of heading date in crop species is well documented; however, the date of anthesis is often less emphasized even though it has important applications for seed quality and yield. Moreover, the relationship between heading and anthesis is not well defined. We propose that growing degree‐days to heading can be used as a good predictor of anthesis date. Using a broad range of 520 diploid perennial ryegrass accessions, anthesis was found to be highly correlated with growing degree‐days to heading, and growing degree‐days to heading could be used to predict anthesis date in historical data sets collected over many years. The ability to adequately predict anthesis will allow seed‐producing farmers to improve seed quality by identifying times when high disease pressure will coincide with anthesis, thus allowing control measures to be applied. 相似文献
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E. Maccarone B. Fallico F. Fanella G. Mauromicale S. A. Raccuia S. Foti 《Industrial Crops and Products》1999,10(3):453-237
The grain oils extracted from six genotypes of Cynara species: two globe artichokes (Cynara scolymus L.), two cultivated cardoons (C. cardunculus L. var. altilis DC.) and two wild cardoons (C. cardunculus L. var. sylvestris Lam.), were analysed in order to ascertain their alimentary value. Oil yield, moisture, acidity, peroxide number, UV spectrophotometry and CIE colour parameters, fatty acids, phytosterols and -tocopherol were determined by standard methods. Cynara species which are most promising in terms of quality and quantity of oil were the cardoons, especially those belonging to the wild cardoon genotypes. Triacylglycerols were the dominant constituents together with very little amounts of phospholipids and glycolipids. The high content of oleic and linoleic acids in a balanced ratio, and the low amount of free acids, peroxides, saturated and linolenic acids ensure a good alimentary quality. Distribution of phytosterols was typical of oil from grain of Asteraceae such as sunflower and safflower. Moreover the optimal -tocopherol content offers a guarantee of stability against oxidation. 相似文献
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Interacting effects of yak dung deposition and litter quality on litter mass loss and nitrogen dynamics in Tibetan alpine grassland 下载免费PDF全文
下载免费PDF全文 The effects of grazing‐induced dung deposition on plant growth and soil attributes are well established, but little is known about dung effects on litter decomposition. Here, we tested effects of yak dung on litter decomposition and nutrient content in a Tibetan alpine meadow. We incubated litter of four common alpine meadow species using litter bags in the field. Two low‐quality species (Kobresia capillifolia and Elymus nutans) with low nitrogen (N), high C/N and Lignin/N, and two high‐quality species, (Saussurea nigrescens and Thermopsis lanceolata) were incubated in monoculture with and without dung addition. Mass loss of leaf litter, fibre fraction (cellulose, hemi‐cellulose and lignin), N and phosphorus (P) were measured after 6, 12 and 18 months of incubation in the field. Dung addition significantly increased decomposition constants for low‐quality litter species, but not for high‐quality litter species. Dung addition promoted cellulose and hemi‐cellulose loss, but lignin loss was not affected by dung addition, except after 12 months for high‐quality litter species. Dung reduced N immobilization after 6 months and did not affect subsequent release in low‐quality litter species, and promoted N release after 6 and 12 months in high‐quality litter species. Regardless of litter quality, dung increased P release after 6 and 12 months. Our results suggest grazing‐induced dung deposition may accelerate C and nutrient turnover, primarily through increasing the mass loss of low‐quality litter, P release from litter and N release from high‐quality litter. The mechanisms underlying the effects of dung deposition need to be clarified in future studies. 相似文献