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1.
诱发谷物胚乳突变的研究进展   总被引:2,自引:0,他引:2  
徐辰武 《核农学通报》1996,17(6):291-295
谷类作物的胚乳是人类食粮和许多生活必需品的主要来源。通过诱发胚乳突变改良谷物品质,已成为作物育种的发展方向之一。本文综述诱发玉米,水稻和麦类等主要谷类作物胚乳突变的研究进展,以推动有关工作的开展。  相似文献   

2.
植物对水分胁迫适应性的生理机理已相继在水稻、小麦、玉米、高梁等作物中得以报道。然而,有关这些性状的遗传控制及其在与逆境下作物生产的关系却了解甚少,由此阻碍了抗性遗传改良的进展。随着基因定位、基因组图谱、基因转移等分子生物学技术的发展,对植物抗逆性状进行分子剖析成为可能。本文综述了主要禾谷类作物对水分胁迫的抗性生理及遗传研究上的最新进展,讨论了植物抗性遗传改良的发展前景。  相似文献   

3.
受污农田中农作物对重金属镉的富集特征研究   总被引:10,自引:0,他引:10  
采用湿法消化法研究了浙江省不同地区农田污水灌溉后水体、土壤和多种农作物各器官的镉含量,分析了土壤污染状况及农作物对重金属镉的富集特征。结果表明:污水和受污土壤镉含量极显著相关(R^2=0.617,P〈0.01)。不同农作物对镉的吸收程度不同,富集系数为紫云英〉水稻〉大豆〉大麦〉玉米〉小麦。未受污染农作物和受污农作物根系及地上部镉含量差异明显,但镉富集系数差异不明显。同一农作物不同器官对镉的累积规律为根系〉茎叶〉果实。不同农作物果实的富集系数为紫云英〉大麦〉大豆〉水稻〉小麦〉玉米。对几种农作物富集系数和吸收系数的比较发现,玉米和小麦根系及茎叶等营养器官富集镉的能力较强,但果实富集量却很低。6种农作物对镉的转移系数为玉米〉大麦〉紫云英〉小麦〉大豆〉水稻,且转移系数介于0.50~0.95之间,说明这几种农作物均对镉有很好的耐性。  相似文献   

4.
测定了谷物籽实、豆类籽实及根茎三类共计15种饲料的磷含量,并应用尼龙袋法测定其在山羊瘤胃内的降解率。结果表明:三类饲料的磷含量存在明显差异,以豆类籽实最高,谷物籽实其次,根茎类最低。饲料种类间磷的瘤胃降解率差异极显著(P〈0.001),谷物类、豆类和根茎类饲料中快速降解磷(A)分别以玉米(88.82%)、豌豆(92.66%)和红薯(94.69%)最高,而以大米、赤豆和木薯为最低。除大麦、大米和小米外,其他饲料的快速降解磷均在60%以上。除小麦外,慢速降解的磷(B)都低于40%。磷在瘤胃中的降解速率(C)都超过10%/h以上,仅大米、小米和土豆的慢速降解部分的降解速率低于10%/h。不同种类精饲料总的可降解磷(A+B)都在80%以上。不同种类饲料磷的有效降解率都随外流速率的增大而下降,除大米和小米外,其他饲料磷的有效降解率都超过了80%。饲料中磷的含量与磷的有效降解率呈显著正相关关系,磷的降解速率与粗脂肪含量呈极显著正相关关系,淀粉含量则与磷的有效降解率呈显著负相关关系,磷的含量与粗蛋白含量间呈极显著正相关关系。上述结果显示,饲料中磷在瘤胃中绝大部分都可释放出来,故配制反刍动物日粮时必须考虑饲料原料中磷的含量及其有效降解率。  相似文献   

5.
谷物纹理特征的识别   总被引:9,自引:4,他引:9  
谷物纹理是谷物的主要特征,为分析识别谷物纹理特征,而建立了综合纹理识别模型。模型包括两部分:一部分是用灰度共生矩阵提取相关纹理特征,包括纹理方向、粗糙度、对比度、同异度,另一部分是用多分形模型提取纹理特征,这部分特征与纹理结构相关,该模型对3种谷物(小麦、燕麦、大麦)的平均识别率是95%。  相似文献   

6.
作物品质除了受品种、生态因素影响外,也受栽培技术的影响。在栽培技术中,施肥方式对不同作物、不同品质成分的作用不同。文章综述了近几年对施肥方式与小麦、水稻、烟、玉米、大麦品质关系的研究状况,供研究、推广时参考。  相似文献   

7.
糯性胚乳小麦的选育   总被引:12,自引:0,他引:12  
在自然界,大多数禾谷类作物,如玉米、水稻、高梁、粟、黍子等,都存在糯性类型.但是由于普通小麦是异源六倍体作物,在它的染色体7AS、4AS和7DS 上各有一个基因,即Wx-A1、Wx-B1 和Wx-D1控制Wx蛋白(淀粉粒束缚淀粉合成酶),Wx蛋白与直链淀粉的合成有关.当三个位点基因全部缺失或不表达时不能合成直链淀粉,只有支链淀粉、自然界不存在三个Wx基因同时缺失的小麦.所以迄今为止尚未发现自然界存在的糯性小麦.小麦面粉中直链淀粉含量是决定面条品质的一个重要因素.本研究以"两个部分糯性"材料作亲本,并结合花粉染色、籽粒剖面染色、SDS-PAGE电泳等手段,在杂种后代中选出了若干糯性小麦品系,定名为"农大糯麦"系列.  相似文献   

8.
施肥方式对作物品质影响的研究近况   总被引:2,自引:0,他引:2  
作物品质除了受品种、生态因素影响外,也受栽培技术的影响。在栽培技术中,施肥方式对不同作物、不同品质成分的作用不同。文章综述了近几年对施肥方式与小麦、水稻、烟、玉米、大麦品质关系的研究状况,供研究、推广时参考。  相似文献   

9.
镉对几种粮食作物子粒品质的影响   总被引:1,自引:0,他引:1  
从营养品质和卫生品质方面综述了重金属镉对水稻、玉米、小麦、大豆子粒品质的影响。土壤中过量的Cd能够影响作物子粒中的淀粉、蛋白质、脂肪、氨基酸等营养成分的含量和比例,也会增加子粒中重金属的含量,威胁人体健康。就目前的情况,相关的研究还是以短期的实验室模拟为主,缺乏长期的田间试验数据支持。  相似文献   

10.
几种禾本科作物对铝的敏感性或耐性   总被引:14,自引:3,他引:14  
通过调查几种禾本科作物根的伸长,根尖的铝含量、铝诱导其根系有机酸的分泌,探讨作物耐铝(铝敏感)性及作物对铝毒害的抵御机理。结果表明,水稻、黑麦是耐铝的作物,而大麦、小麦(Scout 66)是对铝敏感的作物,玉米和高梁对铝敏感性较小麦弱。小麦和玉米品种间对铝的敏感性差异显著,而高梁对铝的敏感性品种间差异性较小。铝能够诱导水稻、黑麦和耐铝的玉米及小麦品种的根系分泌柠檬酸和/或苹果酸。这表明铝诱导有机酸的分泌是它们抵御铝毒害的机理。  相似文献   

11.
Transport of cadmium from soil to grain in cereal crops: A review   总被引:2,自引:0,他引:2  
Due to rapid urbanization and industrialization, many soils for crop production are contaminated by cadmium(Cd), a heavy metal highly toxic to many organisms. Cereal crops such as rice, wheat, maize, and barley are the primary dietary source of Cd for humans, and reducing Cd transfer from soil to their grains is therefore an important issue for food safety. During the last decade, great progress has been made in elucidating the molecular mechanisms of Cd transport, particularly in rice. Inter-and intraspecific variations in Cd accumulation have been observed in cereal crops. Transporters for Cd have been identified in rice and other cereal crops using genotypic differences in Cd accumulation and mutant approaches. These transporters belong to different transporter families and are involved in the uptake, vacuolar sequestration, root-to-shoot translocation, and distribution of Cd. Attempts have been made to reduce Cd accumulation in grains by manipulating these transporters through overexpression or knockout of the transporter genes, as well as through marker-assisted selection breeding based on genotypic differences in Cd accumulation in the grains. In this review, we describe recent progress on molecular mechanisms of Cd accumulation in cereal crops and compare different molecular strategies for minimizing Cd accumulation in grains.  相似文献   

12.
三大粮食作物产量潜力与产量差研究进展   总被引:17,自引:4,他引:17  
产量潜力和产量差的研究对揭示未来粮食增产潜力,有针对性地制定提高作物产量的措施具有重要意义。通过总结近年发表的64篇经典文献,本文总结了世界三大粮食作物小麦、水稻和玉米的产量潜力和产量差的研究进展,并对定量产量潜力和产量差的4种常用方法进行了比较分析。研究表明:1)当前全世界小麦、水稻、玉米的平均产量潜力分别为6.7 t-hm-2、8.1 t-hm-2、11.2 t-hm-2,农户产量分别实现了产量潜力的60%、60%、53%。2)模型模拟是目前定量评估产量潜力最为有效的方法之一,综合使用模型模拟和高产纪录两种方法进行比较分析产量潜力结果会更加可靠;试验产量和高产农户产量一般会低于模型模拟产量潜力,对探索农户短期内增产潜力具有重要意义。3)优化栽培管理措施比如应用土壤-作物综合管理系统等方法是缩小产量差的有效途径。因此,当前三大粮食作物具有较大增产潜力,如何有效缩小产量差、提高作物产量、保证粮食安全是未来需要关注的重点。  相似文献   

13.
Cereal grains such as wheat, rice, and maize are widely consumed as a staple food worldwide. Lead (Pb) is one of the non-essential trace elements and its toxicity in crops especially cereals is a widespread problem. The present review highlighted Pb toxicity in cereal and management strategies to reduce its uptake in plants. Lead toxicity reduced the cereal growth, photosynthesis, nutritional value, yield, and grain quality. The response of cereals to excess varies with plant species, levels of Pb in soil, and growth conditions. Reducing Pb bioavailability in the soil is a viable approach due to its non-degradability either by microbes, chemicals, or other means. Cultivation of low Pb-accumulating cultivars may reduce the risk of Pb toxicity in plants and humans via the food chain. Use of plant growth regulators, microbes, organic, and inorganic amendments might be promising techniques for further decreasing Pb contents in shoot and grains. Soil amendments along with selecting low Pb-accumulating cultivars might be a feasible approach to get cereal grains with low Pb concentrations. Furthermore, most of the studies have been conducted under controlled conditions either in hydroponic or pots and less is known about the effects of Pb management approaches under ambient field conditions.  相似文献   

14.
氮(N)是植物生长发育需要量最大的矿质营养元素,也是作物产量的限制因子。硝态氮(NO3--N)是植物吸收利用氮素的主要形态之一。目前,植物中已报道4个基因家族(NPF、NRT2、CLC和SLAC1/SLAH)参与硝态氮的吸收和利用,其中NPF基因家族成员数量众多且功能多样化,近年来获得较多关注和深入研究。模式植物拟南芥和主要粮食作物水稻、玉米和小麦中,分别含有53、93、79和331个NPF基因。拟南芥NPF家族中已有超过一半成员(31/53)的生物学功能被解析,粮食作物水稻中NPF基因功能亦有较多报道。研究表明,NPF基因广泛参与了植物对氮素的吸收及其调控、转运、分配/再分配等过程,一些成员对于改良和提高作物氮素利用率(nitrogen use efficiency, NUE)具有重要作用。因此,从氮素进入植物体及其在植物体内流动的层面出发,发掘具有重要功能的候选NPF基因,对于解析植物利用氮素的分子机制及其遗传改良具有重要意义。本文综述了模式植物拟南芥以及粮食作物中已报道的NPF基因在氮素吸收和利用中的生物学功能。目前粮食作物玉米中仅有4...  相似文献   

15.
Genomics is providing a new set of tools for cereal chemistry. Analysis of the DNA of the major cereals is increasing the understanding of the basis of grain quality at the gene level. Differences in the sequence of the gene in different cultivars or differences in the level of expression of the gene may be used to explain differences in processing or end-use quality characteristics. For example, quantitative analysis of the levels of expression of genes at different stages during seed development in wheat or germination in barley can be used to define the genetic basis of differences in wheat and barley quality. Rice quality traits such as fragrance and gelatinization temperature (cooking temperature) can be explained by DNA sequence differences in specific genes identified using genomics approaches. Rapid and reliable species and cultivar identification based on DNA analysis methods developed using genomics tools can be applied to grain and to food products. This technology has special advantages in the analysis of complex mixtures of cereals. Technologies for very high-throughput and very low-cost analysis of large numbers of samples are now available. These may be applied by cereal chemists at many levels: selection in cereal breeding, optimizing processing, and analysis of the identity and composition of grain or food samples.  相似文献   

16.
Summary In a collaborative effort between the USDA-ARS and CAAS, 50 accessions each of perennial Triticeae held at the Forage and Range Research Laboratory, Logan, Utah, U.S.A. and the Institute of Crop Germplasm Resources, Beijing, People's Republic of China were exchanged. Eighty six and 85 accessions of these germplasms were screened for powdery mildew (caused by Erysiphe graminis DC) and barley yellow dwarf virus (BYDV) strain GPV, respectively. Fifty seven and 72 accessions had resistance to powdery mildew and BYDV, respectively. These materials are valuable genetic resources for breeding disease resistances in three of the major cereal crops — wheat, barley, and rye.Abbreviations BYDV barley yellow dwarf virus - ELISA enzyme-linked immunosorbent assay  相似文献   

17.
【目的】施用锌肥是改善作物缺锌、 提高产量和籽粒锌含量的重要措施。锌肥的施用效果受多种因素的影响,通过总结自70年代以来锌肥施用对我国主要粮食作物小麦、 玉米、 水稻产量的影响,分析不同年代、 锌肥施用方式、 锌肥用量对这三大作物产量影响的进程,探讨锌肥的适宜用量和施用方式。【方法】利用万方数据库、 中国知网,查阅了1970至2013年间,我国主要粮食作物水稻、 小麦和玉米锌肥施用相关的田间试验文献333篇,剔除文献中没有产量数据、 没有具体施肥相关信息如施肥量、 施肥方式等文献,有效样本数总计为1656个。采用相关分析、 方差分析等统计分析方法,Microsoft Excel 2010软件分析。【结果】锌肥增产效果受锌肥施用方式、 施用量、 年代的影响,具体结果如下, 1)锌肥施用方式土壤施用、 叶面喷施和种子处理在小麦上的平均增产率分别为11.3%、 10.0%和11.1%; 在玉米上的平均增产率分别为13.7%、 12.7%和12.1%; 水稻上的平均增产率分别为15.0%、 9.8%和9.7%。与叶面喷施和种子处理相比,无论是小麦、 玉米还是水稻,土施锌肥的增产效果最好。2)锌肥施用量小麦、 玉米和水稻的增产率随土施锌肥量增加而增加,当施锌量达到一定量后,随施肥用量的进一步增大,增产率有所降低。小麦、 玉米和水稻土施锌肥的合适用量分别为1545 kg /hm2、 2030 kg/hm2、 2030 kg/hm2。小麦增产率与喷施锌肥的浓度关系不明显,叶面喷施浓度在0.4%~0.5% ZnSO47H2O时增产效果最佳; 而玉米、 水稻增产率和叶面喷施锌肥的浓度变化趋势与土施锌肥变化趋势一致。过去40年玉米和水稻适宜喷施锌肥浓度分别是0.1%~0.3%、 0.2%~0.4% ZnSO47H2O。3)施肥年代随着年代的变化,不同作物施用锌肥的增产幅度不同。随着年代的推进,同一锌肥施用方式在小麦上增产率呈逐渐增高的趋势; 锌肥土施和叶面喷施在玉米上的增产率呈下降趋势; 锌肥土施在水稻上的增产率呈下降趋势,而叶面喷施在水稻的增产率呈先降低后增加的趋势; 种子处理方式在水稻和玉米上的增产率随年代的变化不明显。【结论】施用锌肥能有效提高小麦、 玉米和水稻的产量,但是其增产效果受锌肥施用方式、 施用量、 年代的影响。因此,今后在锌肥施用方面,农户应根据作物、 土壤、 环境等条件,选择恰当的施肥方式及锌肥用量,来提高锌肥的增产效果。  相似文献   

18.
A variety of nutrients and some undesirable components are found and possibly concentrated in outer layers of cereal grains. There is a need to develop simple, efficient, and inexpensive laboratory methods in decorticating cereal grains for physicochemical and nutritional characterization and end-use exploration. This study focused on using a Strong-Scott barley pearler (BP) to abrade barleys and investigated factors that could affect kernel breakage, uniformity of abrading, repeatability, and quality of resulting fractions. Results show that the smaller the sample size, the higher the rate of surface removal. The difference in % removal among pearling times decreased as sample charge size increased. Screens with smaller holes (larger number of mesh per inch) decreased abrading efficiency but reduced kernel breakage significantly. The successive pearling mode (several pearling cycles per sample) not only provided a means to collect different fractions of outer layers and remaining kernels but also minimized kernel breakage and gave more uniform removal of outer layers among seeds as compared with the continuous pearling mode (only one pearling cycle per sample). As pearling progressed, the surface color of both outer layer and abraded kernel fractions became whiter. Subsequent trials with several other cereal grains (wheat, rice, sorghum, and oats) confirmed these findings. In conclusion, when modifications of equipment and procedures are made, the BP can be used as an efficient and inexpensive alternative for abrading various species of cereal grains.  相似文献   

19.
Dehydrooligomers of ferulic acid cross‐link polysaccharides such as arabinoxylans and pectic polysaccharides in cereal and certain pseudocereal grains, affecting physiological effects of these fiber components and their physicochemical properties during food processing. An HPLC‐MS method for the analysis of eight diferulic acids and five triferulic acids in low‐lignin samples such as cereal grains and pseudocereals was developed and validated. This method was applied to the analysis of ester‐linked diferulates and triferulates in maize, popcorn, wheat, rye, oats, barley, buckwheat, and amaranth, giving a complete profile of this set of diferulates and triferulates in cereals and pseudocereals. Triferulic acid contents of the cereal flours are roughly 1/10 of the diferulic acid contents, ranging between 23 (oats) and 161 (popcorn) μg/g of flour, with lower amounts for the pseudocereal flours (1–3 μg/g of flour). Dominating trimers are either the 5‐5/8‐O‐4‐ and/or the 8‐O‐4/8‐O‐4‐regioisomers with lower proportions of 8‐8cyclic/8‐O‐4‐, 8‐5noncyclic/8‐O‐4‐, and 8‐5noncyclic/5‐5‐triferulic acids. A unique diferulate pattern was found for buckwheat, with more than 90% of the dimers being 8‐5‐coupled. Amaranth contains an unusually high proportion of 8‐8cyclic‐diferulate, with 27% of the total dimers, whereas oats and barley show comparably high proportions (23%) of the 8‐8tetrahydrofuran diferulate.  相似文献   

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