作物柱头外露性状研究进展

柱头外露作为一个能提高作物杂交制种产量的重要性状,被广泛应用于杂种优势利用育种中。柱头外露性状多数是数量性状,遗传规律因作物种类和基因型的不同表现出多样性,是近年来作物领域的研究热点。深入解析作物柱头外露的遗传控制机制和调控机理,对于提高作物杂种优势利用效率具有重要意义。本文从柱头外露性状的经典遗传学解析、相关基因的克隆与分析、育种利用及研究存在的问题与展望等几个方面,综述了作物柱头外露性状的研究进展。     

短季棉早熟性的遗传效应及其与环境互作研究

以熟期不同的9个棉花品种为亲本,按部分双列杂交配制46个组合的F1、F2,在3个不同生态环境条件下,研究了7个早熟相关性状的遗传效应及其与环境互作。结果表明:短季棉7个早熟相关性状的遗传均以加性效应为主,同时存在着显性效应,对于播种-现蕾、播种-开花和现蕾-开花还存在着上位性效应;短季棉各早熟性状的遗传效应与环境互作显著。生育期、播种-开花的狭义遗传率均较高,分别为66.1%和49.1%,且与环境互作效应较小,而果枝始节和播种-现蕾的遗传率最低,分别为19.8%和18.8%,且与环境互作达到极显著水平,现蕾-开花、开花-吐絮和株高这3个性状的遗传率及其与环境互作居中。由此说明:早熟性的遗传受环境影响较大,在生态条件差异较大的育种地点,以果枝始节和播种-现蕾作为早熟性指标进行异地选择是不可靠的,而以生育期、开花期为早熟性选择指标是比较可行的。     

早熟甘蓝型油菜研究进展及其应用北大核心CSCD

随着油-稻-稻三熟制种植模式的推进和油菜机械化生产的要求,早熟性状已经成为油菜理论研究和品种选育的关键性状。本文从油菜早熟性状的理论研究、品种选育以及生产应用的层面开展了综合论述。首先介绍了早熟油菜的界定标准及其生长特性和选择依据。随后从早熟性状的遗传特性、早熟基因的定位等层面介绍了早熟性状的理论研究现状。在品种选育和应用层面,从早熟品种选育的必要性、早熟品种的选育途径、育种现状以及早熟油菜品种生产应用现状和前景等方面开展了论述。最后针对油菜早熟性方面存在的问题和对策作了简要概述。本文将为我国早熟油菜种质创新和品种选育提供参考。     

上位性及其在遗传育种研究中的应用

上位性引入遗传学已有一个多世纪,直到近些年才受到广泛关注,成为复杂性状遗传研究体系的一个重要组成部分。上位性可分为统计上位性和功能上位性两类,前者具有群体特性,后者属于基因型现象。分子标记技术是研究上位性的一个有力工具,理论与实验研究证实上位性在动植物数量性状的表现中具有重要作用。上位性在作物育种中的应用因作物的繁殖方式,育种方法等不同而异,上位性是杂种优势形成的重要遗传基础。     

作物抗倒伏相关性状及其信号转导调控机理的研究进展

倒伏是影响作物品种选育和产业化推广的重要限制因子,会使作物籽粒与秸秆的产量和品质显著降低且易引发病虫害,不利于机械化收割使作物经济效益显著降低。株高、茎秆强度、壁厚、分蘖数、分蘖夹角等性状同作物茎秆抗倒伏特性密切相关。倒伏主要分为为根倒伏和茎倒伏,茎倒伏与茎秆特性相关,其中株高与分蘖数分别受赤霉素信号转导和独脚金内酯信号转导的调控;根部各性状主要受生长素、乙烯以及细胞分裂素等激素信号转导的调节。本文对植物抗倒伏相关性状与抗倒伏的关系以及各重要性状相关信号转导途径方面的研究进行综述,并对基于激素信号转导途径的作物抗倒伏性状改良和分子育种今后的研究方向进行了展望。     

早熟甘蓝型油菜研究进展及其应用

随着油-稻-稻三熟制种植模式的推进和油菜机械化生产的要求,早熟性状已经成为油菜理论研究和品种选育的关键性状。本文从油菜早熟性状的理论研究、品种选育以及生产应用的层面开展了综合论述。首先介绍了早熟油菜的界定标准及其生长特性和选择依据。随后从早熟性状的遗传特性、早熟基因的定位等层面介绍了早熟性状的理论研究现状。在品种选育和应用层面,从早熟品种选育的必要性、早熟品种的选育途径、育种现状以及早熟油菜品种生产应用现状和前景等方面开展了论述。最后针对油菜早熟性方面存在的问题和对策作了简要概述。本文将为我国早熟油菜种质创新和品种选育提供参考。     

玉米不同生育阶段和主茎叶数的基因效应与相关

生育期是玉米育种的重要目标性状。前人 对玉米生育期基因效应所作的一些报道,结论 不尽相同L8"121。在生育期的相关性方面研究较 多,但偏重于同一生育阶段亲子间的相关和同 一世代不同生育阶段间的相关L,一,,81。玉米主茎 叶数与生育期,特别与开花期有非常密切的关 系,但对其基因效应却研究不多〔61。为进一步 明确玉米生育期方面有关性状的基因效应,本 文利用遗传基础较广泛的材料,用不同的方法 分析了不同生育阶段和主茎叶数的基因效应, 以期对生育期育种制定方案有所帮助。在相关 性方面,我们在前人工作的基础上,进一步研究 了不同世代不同性状间的相关,即亲本吐丝期、 灌浆期、主茎叶数与F;成熟期的相关1u为玉米 早熟性育种更简捷地利用相关性状提供参考。 玉米成熟的标志不够明确,记载标准不易掌握, 加之病害、倒伏等原因,准确记载成熟期比较困 难,甚至无法记载。因此,利用上述的相关关系 有一定的实践意义。     

陆地棉丰产性状的遗传力和遗传进度的估测

早熟、丰产、优质、抗病是当前我国棉花育种的主要目标。为了加速我国棉花育种工作的发展,多快好省地培育棉花新品种,必需以阶级斗争为纲,坚持党的基本路线,在华主席和党中央的统一领导下,充分发动群众,研究棉花的早熟、丰产、优质、抗病等项经济性状的遗传规律,把育种工作置于更有科学预见性的基础之上。关于陆地棉的纤维长度、早熟性的遗传力,我们曾做过一些初步估计,本文拟对陆地棉丰产性状的遗传力和遗传进度再进行一些初步估测。     

水稻粒形性状的遗传及相关基因定位与克隆研究进展

作物育种的首要目标是提高产量。水稻粒形是与水稻产量性状直接相关,与品质性状存在着密切关系的数量性状,其评价指标主要是粒长、粒宽、粒厚、长/宽和长/厚。近年来,水稻粒形的数量遗传研究取得了重要进展,并成功定位克隆了一批控制水稻粒形的基因。文章综述了水稻粒形的经典遗传研究、QTL定位、粒形基因的克隆和功能分析以及在水稻超高产育种中的利用。     

蔬菜作物重要农艺性状相关基因分离的研究进展

本文简要综述了蔬菜作物基因分离的主要方法和近年来蔬菜作物重要农艺性状相关基因分离的研究进展,指出在分离蔬菜作物目的基因的研究中,必须加强基因分离的原创性;充分利用现有的研究条件,做到基因分离与功能基因组研究相互协调,均衡发展,从而为我国蔬菜作物开展分子育种研究奠定基础。     

Genetic analysis and gene detection of fructan content using DArT molecular markers in spring bread wheat (Triticum aestivum L.) grain

Molecular Breeding - The concentration degree of floret flowering date (CDFFD) is an important selection index for earliness breeding of peanut, while the genetic basis of CDFFD-related traits in...     

海岛棉产量和早熟性相关性状的QTLs定位

对海岛棉产量和早熟性状进行QTL初步定位,为分子标记辅助育种提供依据。利用5200多对SSR引物筛选海岛棉品种新海3号和Giza82间的多态性引物,获得107对。以多态性引物检测新海3号×Giza82的190个F2:3家系,获得120个多态性位点。利用JoinMap3.0分析软件构建了一个包含22个连锁群,74个标记,标记间平均距离12.06 cM,全长893 cM,覆盖海岛棉基因组20.12%的分子标记遗传连锁图谱。采用复合区间作图法检测到21个与海岛棉产量性状和早熟性状有关的QTL,其中早熟性状检测到12个QTL,分别位于1、3、5、6、11、17、22共7个连锁群上;产量性状检测到9个QTL,分别位于1、4、5、6、7、16、22共7个连锁群上。研究结果为海岛棉产量性状和早熟性状的分子设计育种提供了有用的信息。     

The development of domestic castor bean production

Shatter resistance, earliness, high yield and plant form best adapted to mechanical harvesting have been the principal and already partly achieved objectives in breeding castor beans, which, along with improvements in harvesting and hulling machinery, increase the prospects for greater domestic production of this crop.     

High-throughput Phenotyping and Genomic Selection:The Frontiers of Crop Breeding Converge

Genomic selection (GS) and high-throughput phenotyping have recently been captivating the interest of the crop breeding com-munity from both the public and private sectors world-wide.Both approaches promise to revolutionize the prediction of complex traits,including growth,yield and adaptation to stress.Whereas high-throughput phenotyping may help to improve understanding of crop physiology,most powerful techniques for high-throughput field phenotyping are empirical rather than analytical and compa-rable to genomic selection.Despite the fact that the two method-ological approaches represent the extremes of what is understood as the breeding process (phenotype versus genome),they both consider the targeted traits (e.g.grain yield,growth,phenology,plant adaptation to stress) as a black box instead of dissecting them as a set of secondary traits (i.e.physiological) putatively related to the target trait.Both GS and high-throughput phenotyping have in common their empirical approach enabling breeders to use genome profile or phenotype without understanding the underlying biology.This short review discusses the main aspects of both approaches and focuses on the case of genomic selection of maize flowering traits and near-infrared spectroscopy (NIRS) and plant spectral reflectance as high-throughput field phenotyping methods for complex traits such as crop growth and yield.     

Most significant genome regions involved in the control of earliness traits in bread wheat, as revealed by QTL meta-analysis

Earliness is one of the most important adaptation traits in plant breeding. Our purpose was to identify the genome regions of bread wheat involved in the control of earliness and its three components: photoperiod sensitivity (PS), vernalization requirement (VR) and intrinsic earliness (IE). A QTL meta-analysis was carried out to examine the replicability of QTL across 13 independent studies and to propose meta-QTL (MQTL). Initial QTL were projected on a recent consensus map (2004). Quality criteria were proposed to assess the reliability of this projection. These criteria were based on the distances between markers in the QTL regions. Chromosomes of groups 2 and 5 had a greater incidence on earliness control as they carry the known, major genes Ppd and Vrn. Other chromosome regions played an intermediate role in earliness control: 4A [heading date (HD) Meta-QTL], 4B (HD MQTL), 2B (VR MQTL) and 5B (IE MQTL). Markers at this four MQTL should prove helpful in marker-assisted selection, to better control earliness.     

Breeding Plants for Resistance to Nematodes

Plant breeders and nematologists have developed improved cultivars of important crop species with resistance to plant-parasitic nematodes. The effectiveness of these breeding efforts has depended on the availability of efficient screening procedures, identification of adequate sources of durable resistance, nature of the nematode feeding habit, and knowledge of the inheritance of resistance. These factors determine to a large degree the breeding method and potential success of the research. Systematic searches for nematode resistance have identified resistant germplasm lines within crop species or from related species. When the resistance gene(s) is from related species, incongruity barriers or sterility of the resulting hybrids often must be overcome. In these situations, backcrossing is usually necessary to incorporate the resistance gene(s) and recover the desirable commercial traits of the crop species. If the resistance gene(s) is present within the crop species, the choice of breeding method depends on the inheritance of the resistance, type of screening procedure, and other important breeding objectives for the species. In the future, plant molecular biologists and geneticists will make available novel sources of nematode resistance through incorporation of transgenes from other genera. These efforts will likely require conventional breeding strategies before commercial utilization of an improved resistant cultivar.     

Promising eco-physiological traits for genetic improvement of cereal yields in Mediterranean environments

Breeding for improved productivity has been tremendously successful in the last half‐century, but needs to be even more efficient in the future. Hope based on contributions from molecular biology for improved yield potential seems to depend upon an improved knowledge of yield physiology. This knowledge may assist breeding either directly, recommending selection criteria, or indirectly identifying simpler traits that could be reliably mapped and selected for through marker‐assisted selection. Physiological traits associated with improved performance under water‐limited conditions, include phenology (that allows the crop to escape stresses) and those associated with improved water use, water use efficiency and partitioning. Undoubtedly, earliness has been the predominant trait improved for under Mediterranean conditions, and may not be a prospective trait for future breeding. Different traits that may confer the ability to the crop for capturing more water, such as deeper root systems or osmotic adjustment, may be unworkable in terms of their direct use in selection and surrogates would be needed. For instance, canopy temperature depression and discrimination against 13C may be used to assess improved ability to capture water (in these cases yield is positively related to discrimination against ¹³C in grains). Early vigour, which allows faster ground coverage, also increases the amount of water actually transpired by the canopy by reducing direct evaporation and presents substantial intraspecific variation, and selection for this trait may be successfully carried out either directly or through the use of vegetation indexes. Improved water use efficiency based on transpiration efficiency is largely restricted to conditions where additional water is not available. A constitutively low stomatal conductance or a high stomatal sensitivity may optimise the transpiration efficiency. In this context, discrimination against ¹³C is also a simple and reliable measure of water use efficiency, and in cases in which no major differences in capturing water is possible discrimination against ¹³C correlates negatively with yield. Substantial further improvements in partitioning may be limited in most cereals.     

Genome editing of potato using CRISPR technologies: current development and future prospective

Potato (Solanum tuberosum L.) has tremendous significance due to its nutritional quality. The mounting pressure of increasing population further reinforces its importance as potato is believed to be a vital crop to meet food needs for population growth. Although conventional approaches of breeding, irradiation/mutagens and introgression of quality and yield related traits have improved potato yield, biotic and abiotic stresses continue to impose crop damages. Modern tools such as CRISPR/Cas have assisted plant scientists in accelerating breeding processes by providing new, simple, versatile and robust technologies. These tools make it possible to eliminate traits that are involved in negative regulation of quality and yield parameters. Besides that, genes of interest can also be introduced in close proximity to specific loci that may remain linked throughout the generations. This review focuses on the endeavors, applications and prospects of CRISPR/Cas-based approaches in potato with the potential to increase sustainable crop productivity.

     

Patterns of trait variation in the diploid wheats (Triticum,Aegilops) and the tetraploid speciesTriticum diccocoides

Eighteen earliness and morphological traits were examined in from 2 to 14 lines each of 10 diploid members of the wheat complex,Triticum-Aegilops, and 15 lines of the tetraploid speciesTriticum diccocoides. In general, earliness traits have the greatest relative between line vs. within line variation of all the traits examined. Within species, earliness traits are the principle set of characters around which evolve between line trait differences, one of the most important oich is leaf dimensions. At the genus level, earliness traits are independent of leaf dimensions and plant height characters. Thus, the pattern of evolution at the genus level is different from that exhibited in each of the species. Biological and evolutionary implications of these findings are discussed.