河南省彩色小麦品种冬春性鉴定研究

为了探索冬春性鉴定指标在彩色小麦上的应用效果,进一步明确新育成小麦品种的春化特性,准确鉴定小麦品种的冬春性类型,防范因品种定性不准造成小麦冬春冻害风险,以冬春性类型不同的小麦品种为试验材料,通过连续3年的春播试验,对彩色小麦冬春性鉴定应用情况进行汇总分析。由试验结果可知,春播二期条件下的抽穗率是评价小麦品种冬春性的根本指标,是彩色小麦冬春性鉴定的最佳指标。     

西藏主要农区青稞品种的遗传多样性分析

采用内含子切接点引物（intron-splice junction primer）和长随机引物的PCR分子标记方法,对来自西藏主要农区的29个青稞育成品种和3个农家种的遗传多样性进行了分析。结果表明,选用的5个引物共扩增出稳定清晰的条带39条,其中26条（66.7%）为多态性条带。根据PCR扩增的条带建立[1,0]型数据矩阵,应用NTSYSpc2.1数据分析软件计算各品种间的遗传相似系数,并据此进行聚类分析,结果表明,西藏主要农区青稞品种间有一定的遗传差异,但总体遗传差异较小,遗传基础相对狭窄;聚类结果与各品种的实际生产利用情况较为接近,可以反映出这些青稞品种较为明显的区域特征。     

STS标记鉴定河南历史主推小麦品种春化光周期基因及与品种冬春性的相关性

为了解河南小麦栽培历史上主推小麦品种春化及光周期基因种类及分布特点,采用STS分子标记鉴定了河南小麦栽培历史上主推的43个品种的4种春化基因Vrn-A1、Vrn-B1、Vrn-D1、Vrn-B3和1个光周期基因Ppd-D1位点的显隐性。结果表明:Vrn-A1、Vrn-B3基因位点均为隐性,Vrn-B1和Vrn-D1显性基因频率分别为7.0%、51.1%,光周期显性基因Ppd-D1a频率为93.0%,研究结果说明河南历史上主推的小麦品种中,隐性春化基因和光周期不敏感的显性基因占主导。鉴定结果还表明,43份品种的春化基因与光周期基因组合有4类,第一类为vrn-A1+Vrn-B1+vrn-D1+vrn-B3+Ppd-D1a;第二类为vrn-A1+vrn-B1+Vrn-D1+vrn-B3+Ppd-D1a;第三类为vrn-A1+vrn-B1+vrn-B3+Vrn-D1+Ppd-D1b;第四类为vrn-A1+vrn-B1+vrn-B3+vrn-D1+Ppd-D1a,其所占频率依次为:7.0%、44.2%、7.0%、41.9%。春性品种至少携带一个显性春化基因Vrn-B1或Vrn-D1,且其光周期基因一定是光周期不敏感基因Ppd-D1a;冬性品种的4个春化基因位点均为隐性或仅含显性春化基因Vrn-D1,光周期敏感的隐性基因Ppd-D1b只在冬性品种中检出。通过鉴定小麦春化基因及光周期基因,我们明确了河南小麦栽培历史上主推品种的春化和光周期基因的种类、组成特点及品种演变趋势,对改良小麦品种适应性具有重要参考价值。     

西藏昌都市青稞产业现状与对策措施

青稞作为昌都市主要粮食作物,青稞产业健康持续发展对全市经济发展具有非常重要的意义。本文阐述了西藏自治区昌都市10年以来青稞产业发展现状,分析了青稞产业发展存在的主要问题、发展优势与市场竞争,并提出"十三五"期间昌都市青稞产业发展规划及对策。     

冬性与春性小麦的杂种性状表现和选择

冬小麦与春小麦的杂种 F₁春性是显性,F₂冬、春性分离,其中春性占大多数;F₃—F₄基本稳定。F₁越冬率比春性亲本明显提高;F₃出现越冬性较好的类型。春性和冬性小麦杂交可以获得春播正常抽穗,而秋播越冬较好的类型。杂种 F₁抽穗期比春性亲本晚;F相似文献   

西藏青稞种子田间管理及病虫草害防治技术研究

青稞是西藏地区标志性农作物,同时也是西藏最重要的一种经济作物,种植时间长、耕作经验丰富,逐渐形成当地特有的饮食文化和农业文明.西藏地区气候特征明显,海拔高、温度低,适宜青稞喜光、耐高寒的生长特性.因此,做好西藏青稞的种植工作,提升其产量,可以有效保障藏区人民的粮食安全,提升其经济效益.基于此,从青稞种子田间管理入手,探...     

西藏春青稞种质资源的特色及利用研究

从西藏各地征集的300余份食用栽培春青稞种质资源,从形态特征、农艺性状、抗锈性和籽粒粗蛋白、β-葡聚糖含量、维生素E等特征特性鉴定、评价。分析结果认为：（1）西藏春青稞多样性极为丰富,如芒、稃和籽粒颜色,具有变异最为丰富,多样性最高的特点;（2）具有早熟、大穗、多粒、棱型多,以及抗锈性强等和耐各种不良环境因素的优良遗传性状;（3）具有密穗、稀穗、裸粒、钩芒、矮生、抗锈等可利用基因潜力巨大等特色;（4）籽粒粗蛋白、β-葡聚糖、维生素E等成份因各地区环境条件不同差异较大。笔者主要对西藏春青稞种质资源中优异种质进行评述,筛选出一批具有一种或一种以上的优良性状的遗传资源,并提供可利用的优良种质,为青稞育种及基因资源的研究提供依据。     

冬青叶马尾藻种群多样性及分子系统学分析

冬青叶马尾藻(Sargassum ilicifolium)是一种大型经济褐藻,对近海岸生态系统的初级生产力有重要的贡献作用。为了解冬青叶马尾藻种群多样性,从三亚、陵水、昌江海尾镇和文昌清澜港收集到24份冬青叶马尾藻样品,通过核糖体DNA内转录间隔区(internal transcribed space, ITS)序列比对,显示其碱基组成和序列长度均具有丰富的多态性。分子系统进化树显示,冬青叶马尾藻类群能以较高的置信度聚集在一支,其中陵水类群和三亚类群的亲缘关系更近。本研究结果可为冬青叶马尾藻资源保护和持续发展与利用提供基础的参考材料。     

Genetic analysis of heading date and other agronomic characters in barley (Hordeum vulgare L.)

Genetic analyses of heading date, tiller number, plant height, grain yield, kernel weight, and plump and thin kernels were made in three six-rowed barley crosses (Hordeum vulgare L.) involving four cultivars. Six populations, P₁ , P₂ , F₁ , F₂ , BC₁ , and BC₂ , from each cross were grown and evaluated at Fargo and Prosper, North Dakota, 1982. Parental means within crosses generally were different except for tiller number. Comparison of generation means suggested that late heading was dominant to early, high kernel weight was dominant to low, and kernel plumpness was influenced by additive gene action. The relationship between yield and heading date was not consistent among crosses and positive r values were quite low. It should be possible to select early maturing, high yielding segregates with plump kernels. Heterosis over the mid-parent was quite similar among crosses for heading date, but there was no heterosis over the high parent. Inbreeding depression was fairly constant for heading date, but was less consistent for yield. The lack of uniformity for estimates of inbreeding depression can be related to environmental variation and to its influence on type of gene action. The ratio of additive to dominance variance was inconsistent among crosses for heading date and yield. These data suggest selection for these characters should be delayed past the F 2 generation. Broad sense heritabilities for heading date ranged from 42 to 86%. Values obtained for grain yield were more consistent among broad sense than narrow sense estimates. Genetic advance estimates were low due to lack of additive variance. This revised version was published online in July 2006 with corrections to the Cover Date.     

Yield QTL affected by heading date in Mediterranean grown barley

Knowledge regarding quantitative trait loci (QTL) has led to remarkable advances in breeding for a variety of traits, some of which have an effect on yield under particular environmental conditions. However, the same yield QTL are not usually found, even in the same population tested in different environments, as a result of large genotype-by-environment interactions. In this study, we aimed at identifying yield QTL in a series of experiments carried out in Spain. We used a barley doubled haploid population derived from a spring by winter cross. The relationship between heading date and yield, and between the principal heading date QTL and yield, changed depending on the environment. Allelic combinations causing early or late heading dates usually did not favour high yield, whereas intermediate heading dates were associated with not only higher variability but also higher yield potential. To identify QTL for grain yield independent of heading date, the population was divided into three classes: Early , Intermediate and Late . We found three new QTL affecting yield only at specific maturity groups. The implications of these findings in relation to barley breeding are discussed.     

Marker-assisted characterization of frost tolerance in barley (Hordeum vulgare L.)

Five molecular markers associated to two frost tolerance QTLs ( Fr-H1 and Fr-H2 ) were tested both on nine Turkish accessions, classified by breeders as highly frost-tolerant, and on a previously described sample of 26 barleys, winter, facultative and spring. Accessions were characterized in terms of frost tolerance under both field conditions and artificial freezing test at −12°C. The Turkish lines resulted to be equal or superior to the most tolerant European genotypes tested, showing that they can be used to improve the frost tolerance of the EU barley germplasm. The marker Hv BM5A ( Vrn-H1 and Fr-H1 ) resulted to be the best predictor for assisted selection within this germplasm, because of its high correlation between allelic variation and phenotypic traits. Only Hv CBF4 of the three Hv CBF markers tested at Fr-H2 was associated to the trait, but at lower significance than HvBM5A . The PCR-based molecular marker of Vrn-H1 can thus be used in barley breeding not only for selection of facultative and winter types, but also for fast routine selection of frost tolerant genotypes.     

Conservation of diversity in bulk populations of barley (hordeum vulgare L.)

Summary A series of experiments was conducted to investigate the effectiveness of mass propagated heterogeneous populations (bulk populations) in preserving genetic and phenotypic diversity. Five genetically broad-based bulk populations of cultivated barley (Hordeum vulgare L.) were employed. All of them were produced originally through mass hybridization that was facilitated by male sterility. Four of these populations had a common origin, but were subsequently propagated in different North American locations. Comparisons between early and advanced generations of these bulk populations revealed loss of variability in all populations for morphological and agronomic characters and very little to none for eight isozyme characters. Populations propagated in different locations differed in levels of residual diversity. The bulk populations were less variable than a random sample of parental accessions. The rapid loss of diversity in bulk populations was considered detrimental to genetic conservation.     

Adaptation of barley (Hordeum vulgare L.) to harsh Mediterranean environments

Summary Differences in development of the apex may be the reason for cultivar differences in adaptation of barley to terminal drought in Mediterranean environments. The present study was conducted to identify apical development patterns of barley adapted to terminal drought stressed Mediterranean environments and to determine plant characteristics which can be used as criteria to select for an adapted development. Thirty-five two-rowed barley (Hordeum vulgare L.) entries were grown at two sites in northern Syria (Tel Hadya and Breda) in 1988/89. Four apical development patterns were observed: a slow or fast vegetative development, depending on the vernalization requirement, combined with a slow or fast generative development, depending on the daylength response of the crop. Early heading was related to fast generative development. Leaf appearance rates on the main shoot were constant during a major part of the pre-anthesis period, but significant differences were observed among development patterns. Genotypic differences in main shoot tiller number were associated with differences in the onset of tiller appearance and not with differences in tiller appearance rate or final leaf number on the main shoot. Since vernalization requirements and daylength responses are largely independent of terminal drought stress, selection for an adapted phenology can be done in favourable environments. Morphological traits related to these responses (winter growth habit, cold tolerance, plant colour, growth vigour, heading date) can be used as criteria for selection for adaptation to low-rainfall Mediterranean environments.     

The grain yield of uniculm barley (Hordeum vulgare L.) in two contrasting environments

Summary Four six-rowed uniculm lines of spring barley were grown in two yield trials at different sowing densities. One trial was grown on light sandy soil in 1990. The second trial was grown on clay soil in 1991 and included the two-rowed, tillering cultivar Golf. In the trial on sandy soil, the grain yield of the uniculm lines approached that of Golf grown in an adjacent trial, but in 1991 when the growing conditions were more favourable, Golf yielded significantly more than the uniculm lines. Uniculm lines apparently perform relatively better under marginal growing conditions than in high yielding environments.The uniculm lines do not conform to the ideotype proposed for wheat by Donald (1968) but the results show that a drastic change in plant type need not to imply a large drop in grain yield.     

Evaluation of Barley (Hordeum vulgare L.) Landrace Populations Originating from Different Growing Regions in the Near East*

This study characterizes barley (Hordcttm vulgare L.) garmplasm that evolved under continuous cultivation in highly drought-prone areas of the Near East. Landrace population:) originating from 70 locations in Syria and Jordan were evaluated under field conditions in Tel Hadia, Svria, on the basis of single head-row progeny performance. Significant genetic variation was found for all traits recorded: seed colour, kernel row number, growth habit, awn barbing, days to heading, culm length, leaf widths, awn length, early growth vigour, lodging score, and mildew resistance. For most traits, large proportions oi the total variation were tound between head progenies tvhh.in single populations. The qualitative traits, growth haba, seed colour, and awn barbing showed higher variation indices in populations originating from the drier regions ol Syria. Populanons from tbe drier regions; headed slightly earlier, had narrower leaves, longer eulms and tended to be more susceptible to lodging and mildew than populations originating in the higher rainfall areas in Syria. For all traits, the variance components resulting from differences among populations within a particular growing region, as well as those among populations from differences regions, were highly significant. This indicates that this germplasm stock contains materials with adaptability to these diverse growing conditions. The vanabili:y present within populations, as well 25 that among populations with similar adaptability, is sufficient to allow successful election for productivity-related traits.     

Variation in developmental patterns of wild barley (Hordeum spontaneum L.) and cultivated barley (H. vulgare L.)

Summary Six wild barley (Hordeum spontaneum) accessions, from a diverse range of habitats, and two spring-cultivated barleys, were examined for variation in durations of development phases. The durations of the leaf initiation and spikelet initiation phases were longer and spikelet growth phases shorter, in wild than in cultivated barley. Across all wild and cultivated barleys the rate and duration of spikelet initiation were negatively correlated, but neither was related to the number of spikelets per spike. The number of spikelets was positively correlated with the number of leaves and the ratio of the number of spikelets to the number of leaves declined with increasing time to anthesis, indicating that each successive leaf was associated with a diminishing increase in the number of spikelets. The duration of culm elongation and final culm length were shorter in accessions of cultivated barley compared with wild barley. This paper also discusses the feasibility for increasing the number of spikelets per spike through breeding for genetic changes in lengths of pre-anthesis phases of development.Abbreviations ANOVA Analysis of variance - HV Hordeum vulgare - CE Culm elongation - DR Double ridge - HS Hordeum spontaneu - ° Cd Degree days