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1.
多年来,育种家们一直致力于籼粳亚种间的杂种优势利用研究。由于亚种间的进化不同而产生的生殖隔离使其F_1的结实率低或近似不育。IKEHASHI·H(1982)研究籼粳不亲和性及由此引起的杂种结实率低的原因,强调“中间型”在克服水稻籼粳杂种低结实的作用,提出了“水稻广亲和现象”。筛选具有广亲和性的品种,成了育种极为重要的工作。1988年发现47粳与籼、粳杂交,F_1结实正常。1990年用广亲和标准测验种对47粳进行鉴定,现将结果报导  相似文献   

2.
水稻广亲和性的研究与利用   总被引:3,自引:2,他引:1  
水稻育种的突破关键是种质资源。进一步提高产量的关键将是籼粳亚种间杂种优势的利用,但结实率低是籼粳亚种间杂交育种的障碍之一,近年来利用广亲和品种是一个有效途径。本文对广东和遗传特性作了解释,评介了广亲和品种的筛选与选育方法,特别是就本院选育的广亲和中粳品系02428的利用与研究作了详细论述。  相似文献   

3.
水稻广亲和系的选育   总被引:5,自引:0,他引:5  
水稻广亲和基因的发现及其遗传研究 ,揭开了籼粳稻亚种间杂种一代半不育现象的遗传本质 ,为利用水稻亚种间杂种优势指明了方向。但是 ,已知的广亲和材料 ,绝大多数为古老的农家品种 ,农艺性状不良 ,如植株太高 ,株叶形披散和生育期很长等 ;不能直接作为选配优良组合的亲本加以利用。因此 ,培育具有优良农艺性状和经济性状、可供实用的水稻广亲和系就显得非常重要 ,这是开展亚种间杂种优势育种的首要任务之一。普通栽培稻有籼稻、粳稻和爪哇稻三个亚种 ,所以亚种间的杂交可分为籼粳交、籼爪交和粳爪交三种形式。初步研究表明 ,水稻杂种优势强弱的程度 ,具有籼粳交 >籼爪交 >粳爪交 >籼籼交 >粳粳交的一般趋势。也就是说 ,亚种间的杂种优势一般要强于品种间的。为了能充分利用各种形式的亚种间杂种优势 ,提高育成强优组合的几率 ,就有必要建立籼、粳、爪三个亚种类型的优良广亲和系。我们在以前工作的基础上 ,近年来开展了水稻广亲和系选育的研究 ,已取得一些进展和结果 ,育成了粳型广亲和系培C3 11,爪哇型广亲和系轮回 4 2 2 ,籼型广亲和系培矮 64以及广亲和光敏核不育系培矮 64S。  相似文献   

4.
几个新育成广亲和系的亲和性和配合力分析   总被引:1,自引:0,他引:1  
对6个新育成的广亲和系进行分类定位和亲和性测定表明,它们都属于偏籼或偏粳中间类型,755、855、1330具有相当于02428的广亲和性,247、275、297对粳稻的亲和性较差;主要经济性状的配合力也存在一定的差异。两系亚种间杂交水稻育种,广亲和系的亲和性好是基础,配合力高是关键,亲和性好且配合力高才有实用价值。  相似文献   

5.
酯酶同工酶在区分籼粳品种类型上是一个有效而可靠的指标.我们以前的研究已确定,水稻品种的酯酶同工酶谱型分为三大类:籼型、粳型和中间型.近年来又发现广亲和品种的酯酶同工酶谱型是属于中间型的13457或粳型的1457(仅Aus373是1247).根据这两种谱型(13457和1457),从种质资源中可初步检出广亲和品种.在这个试验里,试图用与籼粳杂交测试的方法,去验证具有广亲和酶谱型品种是否有广亲和性.  相似文献   

6.
水稻籼粳特异性RFLP标记及广亲和品种亲缘关系分析   总被引:14,自引:1,他引:14  
 应用160个RFLP标记分析了21个水稻广亲和品种6个籼粳测验种,发现其中68个标记可以区分籼粳测验种。21个广亲和品种根据与籼粳测验和共有片段比率的大小 可以分为籼,粳和籼粳中间型三类。68个标记在15个籼粳品种中进一步筛选,得到24个籼粳特异性RFLP标记。它们在亚种内杂交带型相同而亚种产不一样。其中RG358、G318为籼稻专一性探针,在粳稻中表现为零等位。以此24个探针为基础构建了广亲和品品种亲缘关系的树状图。讨论了籼粳特异性RFLP标记在水稻遗传育种实践中的应用。  相似文献   

7.
 搜集典型籼粳品种、广亲和品种、偏籼或偏粳品系及恢复系并进行杂交。选取25个籼粳亚种间杂种F1,将其划分为5类。以这5类25个组合的生物产量、茎叶重、秆高、出穗期、每穗颖花数、实粒数、结实率等性状为基本资料,分别计算其超亲优势与竞争优势。结果指出:籼粳亚种间杂种F1茎叶重与结实率存在负相关,杂种优势含可利用与非可利用两部分,典型籼粳F1杂种优势是难以利用的,利用广亲和系与偏籼或偏粳恢复系及其派生系或者偏籼广亲和系和偏粳广亲和系配组,实现部分利用亚种间杂种优势,应作为当前亚种间杂种优势利用育种战略的重要措施。  相似文献   

8.
 通过籼粳杂交、广亲和特性鉴定以及育性恢复能力测定等手段,选育出CH58、CH59、C18和C84四个籼粳中间型广亲和恢复系。生物学特性研究结果表明,CH58、CH59、C18和C84的程氏指数分别为11、13、13和15,其中CH58、CH59和C18的籼粳属性为偏籼,C84为偏粳。广亲和特性鉴定和育性恢复能力测定结果表明,四个恢复系具有良好的广亲和性,且都能恢复滇型、BT型、矮败型等粳稻不育系以及野败型、印水型等籼稻不育系的育性,恢复谱广。花时特性研究表明,籼粳中间型广亲和恢复系的开花高峰要明显早于粳稻不育系春江16A。粳不籼恢亚种间杂交稻在单株产量、每穗粒数、二次枝梗数、株高、一次枝梗数和剑叶宽等性状上表现出明显的中亲优势和竞争优势。利用CH58等四个籼粳中间型广亲和恢复系与粳稻不育系配组,已选育出春优58、春优658、春优59、春优618等粳不籼恢亚种间杂交稻,已通过国家、浙江省等品种审定。CH58等四个籼粳中间型广亲和恢复系广亲和性好,恢复谱广,在三系法籼粳亚种间杂种优势利用中具有良好的应用前景。  相似文献   

9.
利用广亲和性基因提高籼粳杂种育性的研究   总被引:3,自引:0,他引:3  
Ketamura.E、Ikehashi.H和笔者等人的先后研究认为,表面上看起来非常复杂的水稻亚远缘杂交的广亲和性由一对主基因起关键作用,如果将这种显性的广亲和性基因转入籼稻或粳稻品种中,可能培育出结实正常的强优籼粳交组合用于生产。袁隆平教授率先在我国利用这种广亲和性基因培育籼粳亚种杂交水稻,提出了杂交水稻超高产育种。作者在他的指导下,进行了本试验的研究。 材料和方法 采用7个籼稻品系和3个粳稻品种为目标亲本,以紫色稃尖为指示性状,目标亲本作为轮回亲本,将CPSLO;,或ketan Nan-zka的广亲和性基因口交导人目标亲本中。培育 T一系…  相似文献   

10.
水稻广亲和种质资源   总被引:1,自引:0,他引:1  
作物育种的实践和成就表明,只有采用崭新的材料与方法,才能在产量和其它方面取得突破。60年代矮化育种和70年代杂交籼稻的育成,主要利用了矮仔粘、低脚乌尖等矮源和野败胞质不育及有恢复基因的、具有良好株型的籼稻种质资源。南朝鲜在籼粳杂交育种上取得理想效果,是利用了IR667桥梁亲本种质等事例,表明水稻育种突破的关键之一是种质资源。根据袁隆平的“杂交水稻育种的战略设想”,积极利用水稻广亲和性种质资源,是加速育成、利用水稻亚种间杂种优势,提高水稻产量的重要途径和物质基础之一。  相似文献   

11.
12.
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   

13.
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   

14.
Evolutionary aspects of the trade-off between seed size and number in crops   总被引:1,自引:0,他引:1  
Victor O. Sadras   《Field Crops Research》2007,100(2-3):125-138
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   


15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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