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本文总结了福建省水稻育种发展过程中,曾经历过矮化育种及三系法的杂种优势利用两次突破,目前正面临第三次突破,即两系法亚种间杂种优势利用。分析了引起三次破性发展的主要因素:一是新的设想,二是材料上的突破。记述了本省今后水稻育种发展战略:应以常规育种为基础,以杂交水稻研究为重点,不断发展育种新技术。常规育种的主攻方向是选育丰、抗、优、适兼顾的中熟早籼从并从类型、熟期、丰产性、抗性、米质等方面加以分析;杂交水稻的研究方向是,三系法发展为两系法,从品种间杂种优势利用发展为亚种间杂交优势利用,同时把两系法与亚种间杂种优势利用溶为一体。常规育种与杂交水稻是相互联系、相互渗透、相互促进的辩证关系。新技术育种必须与常规育种紧密结合,取长补短,发挥各自优势。 相似文献
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选育水稻亚种间杂交组合的策略 总被引：55，自引：8，他引：55
选育水稻亚种间杂交组合的策略袁隆平（国家杂交水稻工程技术研究中心，长沙４１０１２５）选育高产亚种间杂交稻，从根本上说，就是要应用育种艺术，克服各种障碍，将水稻亚种间强大的生物杂种优势协调地转化为经济产量优势，特别是要把解决杂种结实率低而不稳和籽粒充实... 相似文献
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水稻超高产育种问题初探 总被引：10，自引：2，他引：10
从历史发展的角度看，我国的水稻育种，已有两次突破，第一次是60年代初矮化育种的成功，把水稻产量提高了20％～30％；第二次是70年代中期杂交水稻的研究成功，水稻产量又在矮秆良种的基础上增长了20％左右[1]，水稻是我国最重要的粮食作物，依靠科技进步，大幅度提高水稻单产，是人多地少的我国面临严峻挑战的必然选择。一、水稻高产潜力与超高产目标80年代以来，国内外兴起了水稻超高产育种热潮。国内杨守仁教授提出理想株型和优势利用相结合的理论［’］。黄耀祥先生提出“半矮秆丛生快长超高产株型模式［’j，周开达提出“重穗型”模式… 相似文献
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水稻双胚苗的发现及其研究进展 总被引：2，自引：0，他引：2
著名杂交水稻育种专家袁隆平提出了杂交水稻育种分为三个发展阶段的战略设想,即:三系法品种间杂种优势利用,两系法亚种间杂种优势利用和一系法远缘杂种优势利用。“一系法”即利用无融合生殖法固定水稻品种间及更远缘的强大的杂种优势。这既是人们愿望,也是杂种优势育种发展的最高阶段。利用无融合生殖特性来固定杂种优势,成功的关键在于获得水稻的二倍体无融合生殖材料。早在1979年袁老师就对我们提出了固定杂种优势的途径和寻找无融合生殖材料的方法。其中不定胚就是二倍体无融合生殖的方式之一。它的主要表现形式是多胚现象。因此从大量… 相似文献
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特异亲和基因及其在杂交水稻育种上利用的设想 总被引：5，自引：0，他引：5
水稻籼粳亚种间杂种优势利用是水稻超高产育种的重要途径之一。然而,水稻籼粳亚种间的子一代普遍存在不育性,一般结实率很低。因此,水稻籼粳亚种间杂种优势利用的关键在于克服杂种的不育性。近年来,Ikehashi和Araki提出“广 相似文献
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杂交水稻的育种战略设想 总被引：130，自引：18，他引：130
(一) 农业生产和作物育种的历史表明,凡在育种上有所突破,就会给农业生产带来一次飞跃。如杂交玉米和高粱,矮秆水稻和小麦等的育成和应用,都大幅度地提高了这些作物的产量。 杂交水稻培育成功,属于水稻育种上的一项突破。生产实践证明,在相同条件下,杂交水稻一般比普通良种增产20%左右。近年来,杂交水稻的种植面积约占全国水稻面积的四分之一,其产量则占稻谷总产的三分之一左右(见表1)。由此可见,进一步发展杂交水稻,对提高我国粮食产量具有十分重要的战略意义。 事物的发展是无止境的,特别是在人为控制下,事物的发展规律是螺旋形上升的。我… 相似文献
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亚种间杂种优势利用的设想与实践 总被引：7，自引：2，他引：7
l亚种间杂种优势利用的提出 30年代日本加藤茂苞等为品种分类进行了籼粳杂交研究。50年代初杨守仁等为将籼稻中的有利基因导入粳稻开始了籼粳杂交育种研究。这些研究指出,籼粳杂种F;具有明显的植株高大、穗大粒多、苗期生长快、分蘖力强、茎粗抗倒、根系发达、再生力和抗逆性好等优势。但籼粳杂交F1的结实率低,长期成为杂种优势直接利用的最大障碍。由于广亲和基因与光敏核不育基因的发现,1986年袁隆平提出亚种间杂种优势直接利用的战略设想,接着全国掀起二系法、三系法亚种间杂交组合选育的热潮。2广亲和材料在籼粳亚种间杂交上的应用 冈… 相似文献
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导言本世纪30年代育成了杂交玉米,促使其它作物包括常异交作物高粱和自花授粉谷类作物例如小麦、水稻、大麦等育种工作者利用杂种产生的原理。品种间杂交F_1比其亲本品种有更好的生产性能,这种杂种活力或称杂种优势现象是遗传控制的。当中国的水稻专家报导杂交水稻在中国首先育成并在生产中应用时,使中国以外的科学家震惊(无名1977)。那时,杂交水稻在中国的推广面积大约200万公顷。这些组 相似文献
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《Journal of Crop Improvement》2013,27(2):81-114
Summary The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices. 相似文献
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Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity. 相似文献
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Whereas the concept that availability of resources drives seed production is sound in principle, it is incomplete as there are many solutions to the allocation of resources that derive from the trade-off between number and size. This paper examines evolutionary aspects of this trade-off in annual grain crops. The analysis is centred on the working hypotheses that, for a given species and environment, allocation of resources to reproduction involves (H1) high plasticity in seed number, which allows for variable resource availability, and (H2) a relatively narrow range of seed size that results from evolutionary and agronomic selection. Comparisons between crops and fish are used to highlight common evolutionary elements in taxa where parents provide little or no care to their offspring, with the consequence that both number and early survival of offspring, hence fitness of parents, are partially related to embryo size and reserves.
The plasticity of seed number in relation to availability of resources is analysed against the established relationship between offspring number and parent growth rate during critical stages. The notion that seed size is under stabilising selection is analysed against three conditions: (1) mean seed size is conservative for a given species and environment, (2) seed size affects fitness, and (3) seed size is heritable. Databases from published papers were compiled to analyse the relative variability of seed size and number, and the heritability of seed size. Evidence for and against the link between seed size and parental fitness is revised using the Smith–Fretwell model as framework (Am. Nat., 108, 499–506).
The proposal of high plasticity of seed number and narrow variability of seed size resulting from stabilising natural selection is generally consistent with evolutionary and genetic considerations. Agronomic selection may have reinforced natural selection leading to relatively narrow seed size in species such as wheat and soybean, where cultivated types retained high plasticity for seed number. In contrast, selection for one or few inflorescences in crops like sunflower and maize may have morphologically reduced seed number plasticity and increased variability of seed size and its responsiveness to resource availability in relation to their wild ancestors. 相似文献
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Yanhua Lu Chongwei Zhang Peter Bucheli Dongzhi Wei 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):55-63
Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China. 相似文献
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Summary The viability of five pathogens was decreased by treatment with hot water when tested in vitro.Polyscytalum pustulans was most sensitive andRhizoctonia solani least sensitive.
Potato tubers were exposed to 55°C for 5 min in a commercial continuous hot water treatment plant using naturally contaminated
seed tubers and tubers which had been inoculated by dipping in comminuted cultures. The frequency of eyes colonised byP. pustulans, Helminthosporium solani, andR. solani was reduced to virtually zero and the effect persisted on tubers subsequently stored at 4°C and at 15°C for up to 16 wk.
Results withColletotrichum coccodes were inconclusive. Treatment suppressedPenicillium spp. which, however, rapidly recolonised the eyes during storage, leading to higher contamination levels in the treated than
in the untreated tubers. With tubers inoculated withPhoma foveata, good control was achieved when the incubation period before treatment was 10 d but not when the period was 42 d. 相似文献
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《Journal of Crop Improvement》2013,27(2):379-400
Summary Heterocyclic 1,4-benzoxazin-3-ones and related benzox-azolinones are important natural products of the cereal crops maize, wheat and rye. Much research has focused on the role of these compounds as defensive agents against plant diseases and pests. Studies of a wide variety of biological effects on herbivores and nematodes, plant pathogenic fungi and bacteria are reviewed in this article. Phytotoxic activity of the compounds is also considered with respect to allelopathic interaction with higher plants. Recent investigations of molecular aspects of interactions of cyclic hydroxamic acids and related benzoxazo-linones with acceptor organisms have demonstrated different effective detoxification strategies and tolerance mechanisms. This research has greatly advanced our knowledge about the multiple roles that these allelochemicals play in ecological systems. 相似文献
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Potential of dry fractionation of wheat bran for the development of food ingredients,part I: Influence of ultra-fine grinding 总被引：1，自引：0，他引：1
Youna Hemery Marc Chaurand Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Vieno Piironen Abdelkrim Sadoudi Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is an undervalued by-product of white flour and has great nutritional potential due to its high content in fibres and bioactive compounds. Micronized bran could be used as a food ingredient to improve the nutritional potential of cereal products, or be used as a starting material for other processes (bioactive compound extraction or bran fractionation). The aim of this work was to find a way to efficiently decrease the particle size of bran. The influence of the grinding temperature (ambient or cryogenic grinding) on the granulometric distribution of particles, their composition, and their microstructure was studied, at lab-scale and pilot-scale. It showed that the intrinsic characteristics of bran (glass transition within intermediate layers at −46 °C) had more influence on its grinding behaviour than the type of grinding device used: the particles size distributions obtained after grinding at lab-scale and pilot-scale were very similar. At both scales, the granulometric curves were narrow for cryogenic grinding, while for ambient grinding they were spread over the whole particle size range. Ultrafine particles were obtained in both ambient and cryogenic conditions. Negative temperatures, by increasing the material’s brittleness, favoured a fast fragmentation of bran: one step of cryogenic grinding allowed a median particle size of nearly 50 μm to be reached, whereas three successive steps of ambient grinding were needed for the same result. On the other hand, ambient temperature favoured the dissociation of the different constituent layers of wheat bran, and produced less composite particles than cryogenic grinding. 相似文献
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Multiple use of plants: Studies on selenium incorporation in some agricultural species for the production of organic selenium compounds 总被引：3，自引：0，他引：3
The technique of spraying plants with inorganic forms of selenium can be employed for phytochemical production of organic selenium compounds. Fractionation of the plant material makes it possible to produce a highly concentrated and well defined selenium supplement with potential use in animal and human nutrition. The fractionation also gives opportunities to combine production of organic selenium compounds with other products, for example plant fibres. Multiple use of plants can contribute to a more efficient utilization of land area (in comparison to monocultures solely adapted to food production). It also gives the opportunity to develop systems suitable for long term fixation of carbon, as long as the plant material is not reoxidised to carbon dioxide. Plant fibres could provide raw material for the production of paper or building materials in combination with the production of organic selenium compounds preferentially accumulated in another fraction of the processed plant. 相似文献
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Summary
Macrosiphum euphorbiae, collected in the field from potato plants infected with potato leafroll virus (PLRV), transmitted the virus to fewer potato
plants in a field trial than did laboratory-rearedMyzus persicae. In the laboratory,M. persicae was the only efficient vector of PLRV fromPhysalis floridana seedlings, potato sprouts or excised leaves toP. floridana. Two clones ofM. euphorbiae and one clone ofAulacorthum solani transmitted PLRV from infected potato plants toNicotiana clevelandii as effeciently asM. persicae but a clone ofAphis gossypii was an inefficient PLRV vector. An isolate of PLRV, whichM. persicae transmitted inefficiently from potato toN. clevelandii, was also transmitted inefficiently byM. euphorbiae andA. solani. 相似文献