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<正>山东启动新项目带动粮食增产近日,山东省正式启动新项目"超高产小麦、玉米创建"工程,计划培育其新品种,预计到2020年带动山东粮食增产20亿kg。据了解,育种团队将完善现代生物育种与常规育种相结合的超高产小麦育种理论与技术体系,并突破小麦品种遗传基础狭窄、超高产小麦育种理论与技术滞后等难题,努力培育出单产     

淮北地区小麦育种现状及发展方向探讨

小麦是淮北地区的主要粮食作物。近年来,随着人口的不断增长及人们生活水平的提高,小麦品种的品质越来越受到关注。根据对淮北地区小麦品种历史及现状的分析,结合笔者在小麦育种方面多年的经验,对今后当地小麦育种的发展方向进行了探讨。     

春小麦克丰2号的遗传基础及其在育种中的应用

分析了克丰2号的遗传基础与在小麦育种中的利用,从而探讨了种质资源的创新与利用。优异种质春小麦品种克丰2号由黑龙江省农业科学院小麦研究所根据生态育种理论,利用国内外亲本,采用阶梯式复合杂交选育而成,具有配合力高、丰产、多抗优质等突出特点。黑龙江省多家育种单位以克丰2号为育种亲本,采用不同育种途径,先后育成了15个小麦品种在生产上推广应用。     

高产耐旱冬小麦育种技术及其评价方法研究

从国家“六五”攻关开始至今，在小麦抗旱育种的理论及方法，新品种选育技术等方面都取得了较大进展。本文根据国内外适应性育种的试验，结合我们多年小麦抗旱育种实践，对培育兼具抗旱节水和高产冬小麦的育种技术及其评价方法进行了探讨；剖析了高产抗旱小麦品种在不同生育环境的产量构成特点；建立了选择鉴定抗旱高产、广适性、稳产性品种的具体程序。     

为了农民的微笑,为了大地的丰收--记新乡市农科院研究员、新麦系列品种育种人赵宗武

在河南小麦育种界,新乡市农业科学院小麦研究所所长赵宗武同志堪称一代奇才。他用人生最珍贵25年的青春时光,书写了一个共产党员对这片热土的一往情深,书写了一个共产党员无私奉献的高尚情怀。他提出了河南省超级小麦育种理论与方法,先后培育出新麦9号等6个省级以上小麦新品种,其中有4个通过国家品种委员会审定。     

加拿大小麦育种及小麦品种管理考察后的思考

2007年7月14～24日，笔者随团赴加拿大进行了为期10天的小麦育种及小麦品种管理考察访问活动。期间，考察团与加拿大农业及农业食品部食品检验署、中加农业发展项目办公室、品种注册办公室、种子生产者协会、种子贸易协会、加拿大小麦局、加拿大农业及农业食品部研究司列桥研究中心、东部谷物与油料研究中心和温尼伯格谷物研究中心的有关官员、专家和育种家，进行了座谈、交流，参观了列桥研究中心的小麦品种试验基地。     

小麦常规育种技术与改进策略研究

小麦的育种方法有很多,而在国内外使用最多的育种方式还是常规育种,也就是种内品种间杂交选育纯种品种,这种方法应用范围最广、成效最大。在小麦育种方面,经过育种家们长期的实践探索也总结出了不少技术和方法,但时代在不停地进步,科学技术也在不停地发展,人们对小麦的需求使得小麦的育种目标发生变化,小麦常规育种方式也应当随着时代变化而不断向前发展。针对小麦常规育种技术的步骤进行了详细的介绍,再提出了时代变化下的发展方向,最后对小麦的常规育种改进策略进行了介绍。     

小麦抗旱性鉴定方法及评价指标研究Ⅰ 鉴定方法及评价指标

为了筛选适宜于小麦品种抗旱性鉴定的方法和指标，笔者概述了小麦抗旱性的概念、类型和鉴定原理，对多种抗旱鉴定方法和评价指标进行了比较分析，阐述了小麦品种抗旱鉴定的特点和要求，确定小麦全生育期旱棚鉴定法和抗旱指数是最适宜于抗旱育种和区试工作采用的综合性鉴定方法和评价指标     

优质超强筋高抗穗发芽小麦品种龙麦 39 及栽培技术

优质超强筋抗穗发芽小麦品种龙麦39系黑龙江省农业科学院作物育种研究所(2019年更名为作物资源研究所)小麦品质育种团队以光温生态育种和品质育种理论方法为指导,利用生态派生系谱法选育出的适合黑龙江省东部麦产区的优质、广适、高抗穗发芽的超强筋春小麦品种。2015年3月通过黑龙江省农作物品种审定委员会审定和推广。     

克旱号小麦动态基因库的建立与利用研究

抗旱类型春小麦品种是黑龙江省农业科学院小麦研究所根据生态育种理论,利用国内外亲本,采用阶梯式复合杂交选育而成。本文分析克旱号小麦动态基因库的建立、开发利用和育种经验。     

Changes in allelic frequency over time in European bread wheat (Triticum aestivum L.) varieties revealed using DArT and SSR markers

A collection of 189 bread wheat landraces and cultivars, primarily of European origin, released between 1886 and 2009, was analyzed using two DNA marker systems. A set of 76 SSR markers and ~7,000 DArT markers distributed across the wheat genome were employed in these analyses. All of the SSR markers were found to be polymorphic, whereas only 2,532 of the ~7,000 DArT markers were polymorphic. A Mantel test between the genetic distances calculated based on the SSR and DArT data showed a strong positive correlation between the two marker types, with a Pearson’s value (r) of 0.66. We assessed the genetic diversity and allelic frequencies among the accessions based on spring- versus winter-wheat type as well as between landraces and cultivars. We also analyzed the changes in genetic diversity and allelic frequencies in these samples over time. We observed separation based on both vernalization type and release date. Interestingly, we detected a decrease in genetic diversity in wheat accessions released over the period from 1960 to 1980. However, our results also showed that modern plant breeding have succeeded in maintaining genetic diversity in modern wheat cultivars. Studying allelic frequencies using SSR and DArT markers over time revealed changes in allelic frequencies for a number of markers that are known to be linked to important traits, which should be useful for genomic screening efforts. Monitoring changes in the frequency of molecular DNA markers over time in wheat cultivars may yield insight into alleles linked to important traits that have been the subject of positive or negative selection in the past and that may be useful for marker-assisted breeding programs in the future.     

Achievements and limitations of contemporary common bean breeding using conventional and molecular approaches

Common bean (Phaseolus vulgaris L.) improvement programs have been successful using conventional breeding methods to accomplish a wide array of important objectives. Specific achievements include the extension of range of adaptation of the crop, the development of cultivars with enhanced levels of disease and pest resistance and breeding lines that possess greater tolerance to drought. The most effective breeding method depends on the expression and inheritance of the trait to be selected and the target environment. Many bean improvement programs use molecular markers to facilitate cultivar development. In fact, several recent germplasm releases have used molecular markers to introgress and or pyramid major genes and QTL for disease resistance. Related species (P. coccineus and P. acultifolius) via interspecific hybridizations remain an important albeit long-term source for resistance to economically important diseases. Slow progress has been made in the improvement of traits such as adaptation to low soil fertility and tolerance to high levels of soluble Al in the soil using conventional breeding methods. The inability to directly measure root traits and the importance of genotype × environment interaction complicate the selection of these traits. In addition, symbiotic relationships with Rhizobium and mycorrhiza need to be taken into consideration when selecting for enhanced biological N fixation and greater or more efficient acquisition of soil P. Genomic examination of complex traits such as these should help bean breeders devise more effective selection strategies. As integration of genomics in plant breeding advances, the challenge will be to develop molecular tools that also benefit breeding programs in developing countries. Transgenic breeding methods for bean improvement are not well defined, nor efficient, as beans are recalcitrant to regeneration from cell cultures. Moreover, if issues related to consumer acceptance of GMOs cannot be resolved, traits such as herbicide tolerance in transgenic bean cultivars which would help farmers reduce production costs and decrease soil erosion will remain unrealized.     

Should spring wheat breeding for organically managed systems be conducted on organically managed land?

Organic spring wheat (Triticum aestivum L.) producers in the northern Great Plains use cultivars which have been bred for conventional management systems or heritage cultivars released before the widespread use of synthetic fertilizers and pesticides. To investigate the feasibility of organic wheat breeding and to determine common genetic parameters for each system, we used a random population of 79 F₆-derived recombinant inbred sister lines from a cross between the Canadian hard red spring wheat cultivar AC Barrie and the CIMMYT derived cultivar Attila. The population, including the parents, was grown on conventionally and organically managed land for 3 years. Heritability estimates differed between systems for 6 of the 14 traits measured, including spikes m⁻², plant height, test weight, 1,000 kernel weight, grain protein, and days to anthesis. Direct selection in each management system (10% selection intensity) resulted in 50% or fewer lines selected in common for nine traits, including grain yield, grain protein, spikes m⁻², and grain fill duration. The results of this study suggest that indirect selection (in conventionally managed trials) of spring wheat destined for organically managed production would not result in the advance of the best possible lines in a breeding program. This implies that breeding spring wheat specific to organic agriculture should be conducted on organically managed land.     

黄淮海麦区四省份小麦品种的农艺性状及遗传多样性分析

小麦品种的遗传多样性在育种工作中发挥着重要的作用。为了明确黄淮海麦区四省份小麦品种遗传多样性的基础,本研究以所收集的黄淮海麦区的河南、河北、山东和陕西四省的近十几年来(1992-2008年)审定的部分(42份)小麦品种为研究材料,以9个农艺性状为基础进行遗传性状的分析。结果表明,不孕小穗数的变异系数最大为61.39%,其次为有效分蘖和穗粒数,千粒重的变异系数最小为6.06%。河南、河北、山东和陕西四省的多样性指数分别为1.83,1.82,1.73和1.62,平均值为1.75。在此基础上,用最长距离法可将42份材料聚为三大类,但是第Ⅱ大类和第Ⅲ大类相差不大,这说明上述四省小麦品种遗传多样性在逐步提高的同时,其遗传基础仍需进一步拓宽。在性状选择上,首先对变异大的性状进行选择是非常重要的;在品种选择上,应注意选择产量、单株粒重和单株粒数均高的品种。     

Comparison of bread wheat varieties with different breeding origin under organic and low input management

In recent years needs have increased to investigate the necessity of breeding cereals for organic agriculture. The aims of this study were (1) to compare 37 bread wheat (Triticum aestivum L.) varieties with different breeding origin under low input conventional and certified organic farming conditions in Austria and Hungary for 3 years, (2) to identify traits highly sensitive to management systems that could be separated according to their suggested selecting environments and (3) to find evidence for the distinctness of organic wheat breeding. According to the results, seven out of the 15 traits assessed during this study showed significant management × genotype interaction meaning that these traits could be the basis of selection for different management systems. Heading date, sensitivity to leaf rust and powdery mildew had high repeatabilities. For economic reasons, it is therefore reasonable to select for these traits in conventional fields even if the selection target is organic agriculture. However, the present study suggests that selection for the other four traits (grain yield, test weight, leaf-inclination and vigorous growth during booting) should be done later in the target environment. The study compared groups of varieties developed by different breeding strategies (organic, conventional and combined strategies). The results of multivariate analyses showed that the organic breeding was distinct from the other two breeding strategies, but the combined and conventional breeding resulted in similar groupings. It is concluded that the selecting environment has measurable effects on the performance of bread wheat varieties under organic and low input growing conditions.     

Genetic diversity of hexaploid wheat cultivars estimated by RAPD markers, morphological traits and coefficients of parentage

Estimates of genetic diversity can be based on different types of data. The aim of this research were to study genetic diversity among Croatian wheat cultivars by random amplified polymorphic DNA (RAPD) markers, morphological traits and pedigree records; to analyse differences between wheat cultivars from two breeding centres; and to evaluate usability of RAPD markers for estimation of genetic diversity among wheat cultivars in comparison with morphological traits and pedigree record data. Studies were conducted on 14 wheat cultivars and breeding lines from two breeding centres in Croatia. For the RAPD analysis 36 primers were screened and the 14 most polymorphic ones yielded 341 polymorphic bands. Twelve morphological traits were used for morphological analysis. Pedigrees were composed of seven generations of ancestors. RAPD markers showed a high level of polymorphism among the cultivars examined and the breeding lines. No significant correlations were observed among the methods tested.     

Farmers’ participation and breeding for durable disease resistance in the Andean region

In the Andean region, the Preduza project and its partners combined breeding for durable disease resistance using locally adapted cultivars and farmer participatory methods. The approach taken resembles participatory variety selection (PVS). Farmers participated in the selection of advanced materials, rather than finished cultivars. This paper describes this approach and reports experiences with farmers–breeders collaboration. As breeders involved farmers as participants, they learned more about the most important criteria of male and female farmers for preferred cultivars in the marginal environments of Andean cropping systems. This approach encouraged the use of locally adapted cultivars (often landraces), made the breeders less dependent on foreign materials, and has resulted in selection and development of new wheat, barley, common bean, quinoa, potato and maize cultivars. Breeding programmes based on crossing locally adapted cultivars followed by selection by the breeders in the early phases of the breeding programmes and by participatory selection with the farmers in the more advanced stages of the breeding programmes appeared successful. It became clear that breeders must be well acquainted with the farmer preferences such as the requirements for specific agronomic, storage, processing and marketing traits. Over a period of five years the centralized formal breeding approach predominantly based on material produced by the international institutes was replaced by decentralized breeding approaches based largely on local germplasm with extensive farmer participation.     

Genomics-assisted breeding: The next-generation wheat breeding era

Common wheat provides approximately 20% of the total dietary calorie intake of human beings. Recent technological advances in whole-genome sequencing and their application in wheat and its progenitor species provide new opportunities to uncover the genetic variation of wheat traits and to accelerate the traditional breeding (TB) strategies in the context of genomics-assisted breeding (GAB). Integration of TB, marker-assisted selection (MAS) and genomic selection (GS) with high-density SNP markers is expected to accelerate the breeding process and to further enhance genetic gain. With the assistance of the next- or third-generation sequencing technologies and high-throughput phenotyping platforms, GAB can now realistically be considered in the following area: (i) genome sequencing and high-quality assembly to uncover new variations, (ii) whole-genome sequence-based association studies, (iii) gene function (or functional gene) identification and (iv) integration of whole genomic breeding information, utilizing multi-omics data and different breeding strategies. We argue that GAB is becoming the preferred strategy in pursuit of new wheat cultivars with superior traits on high yielding, high nutritional quality, climate-resilience and so on.     

Genetic gains for physiological traits associated with yield in soft red winter wheat in the Eastern United States from 1919 to 2009

Wheat (Triticum aestivum L.) breeding strategies can benefit from periodic evaluation of genetic gains for physiological and morphological traits, and their contribution to yield progress over time in a particular environment. The objective of this research was to expand the recent work at Virginia Tech on genetic yield improvement in soft red winter (SRW) wheat and determine the magnitude of progress for several physiological traits in 50 SRW wheat cultivars released from 1919 to 2009. Physiological traits evaluated here were extensively reported in the literature to be relevant for future wheat breeding as they directly contributed to yield increase under optimum and suboptimal environmental conditions; these traits include canopy temperature depression (CTD), flag leaf width (W), flag leaf area (LA), flag leaf dry weight (DW), flag leaf specific area (SLA), SPAD (soil plant analysis development) chlorophyll reading, and grain ¹³C isotope discrimination (Δ). Replicated experiments were performed at Warsaw and Holland, VA, in 2009–2010 and 2010–2011 growing seasons. Results showed that three traits consistently changed in magnitude over time and, at the same time, were significantly (p < 0.01) related to yield; they were LA, smaller leaf area-higher yields; DW, lighter leaves-higher yields; and Δ, higher Δ-higher yields. CTD decreased in magnitude and SLA, W, and SPAD chlorophyll reading did not significantly change over time. Our data suggest that further yield increase in the SRW wheat grown in eastern Unites States can be achieved through selection of cultivars with smaller leaves, and with high Δ.     

Allelic changes in bread wheat cultivars were associated with long-term wheat trait improvements

Genetic impacts under selective breeding of agricultural crops have been frequently investigated with molecular tools, but inadequate attention has been paid to assess genetic changes under long-term genetic improvement of plant traits. Here we analyzed allelic changes with respect to wheat trait improvement in 78 Canadian hard red spring wheat cultivars released from 1845 to 2004 and screened with 370 mapped SSR markers. The improvements in quality, maturity, yield, disease, stem rust, leaf rust, sawfly resistance, and agronomy were considered. A total of 154 (out of 370) loci with significant allelic changes across 21 chromosomes were detected in the 78 wheat cultivars separated into improved versus non-improved groups for eight traits. The number of significant loci for improving a trait ranged from four for quality to 68 for yield and averaged 35. Many more loci with significant allelic reduction for improving a trait were detected than those with significant allelic increase. Selection for early maturity introduced more alleles, but improving the other traits purged more alleles. Significantly lower numbers of unique alleles were found in the cultivars with improved traits. The distributions of unique allele counts also varied greatly across the 21 chromosomes with respect to trait improvement. Significant SSR variation between two cultivar groups was observed for improvement in seven traits, but not in stem rust. The proportional SSR variation residing between two groups ranged from 0.014 to 0.118. The proportional SSR variations within the improved cultivar groups consistently were much lower than those within the non-improved groups. These findings clearly demonstrate the association between allelic changes and wheat trait improvements and are useful for understanding the genetic modification of the wheat genome by long-term wheat breeding.