Tagging quantitative trait loci for dormancy, tuber shape, regularity of tuber shape, eye depth and flesh colour in diploid potato originated from six Solanum species

Potato breeding aims at breeding diversified cultivars not only suitable for different purposes, but also resistant to diseases, such as late blight caused by Phytophthora infestans , which is a major constraint in potato production. Resistance to P. infestans has been previously introduced into the diploid hybrid population 98-21 from Solanum verrucosum and Solanum microdontum . In the present study, we assessed the segregation of tuber dormancy, tuber shape, regularity of tuber shape, eye depth and flesh colour in this population. Quantitative Trait Loci (QTLs) affecting these important quality traits were tagged using the genetic map developed for this population to locate QTLs for late blight resistance. The most prominent QTL for dormancy was detected on chromosome II and explained 7.1% of the variance. The most important QTLs for tuber eye depth, flesh colour, shape and shape regularity were identified on chromosomes X ( R ² = 14.7%), IV ( R ² = 5.8%), II ( R ² = 8.0%) and III ( R ² = 10.4%) respectively. All traits were also affected by minor QTLs. The obtained results improve our understanding of the inheritance of traits relevant for variety development in potato.     

亚麻品种白粉病田间抗病性分析

调查出宾川县15个亚麻品种田间白粉病的始发期、盛发期和衰退期,以及发病最重时期、恢复生长期和恢复生长率。15个品种田间抗病性差异显著,没有免疫(I)品种,高抗(HR)品种1个、中抗(MR)品种2个、中感(MS)品种2个、感病(S)品种6个、高感病(HS)品种4个。分析出高抗(HR)和中抗(MR)的双亚7号和黑亚11号、范妮,这3个品种发病较迟、抗病性强、成株率高、综合经济性状好、优质原茎比例大、综合产值高。     

基于基因组学的作物抗旱改良

随着基因组学的发展,利用大量的序列信息鉴定和克隆抗旱相关基因以改良作物的生产性能具有重要意义。作物抗旱性属数量遗传,其数量性状位点的鉴定是分子标记辅助选择改良作物抗旱性的基础。笔者就作物抗旱基因鉴定及相关功能基因组学的最新进展作系统的介绍,并探讨了今后作物抗旱性研究发展方向。     

茬口和施氮水平对小麦品质性状及其变异系数的影响

通过在山西省临汾市尧都区建立夏季小麦收获后复播大豆、油葵、玉米和夏季休闲4个茬口,进行不同茬口、施N水平对下季种植的小麦品质性状及其变异系数的研究.结果表明:小麦千粒重、容重、蛋白质含量、沉降值及湿面筋品质性状等各茬口问存在差异,大豆茬口可较好地协调各品质性状.千粒重和容重在休闲茬口中均以高N水平(E、F)较高,而在其他茬口中则以低N水平较高;蛋白质含量、沉降值和湿面筋3个性状在4个茬口中的平均值则以高N水平(E)较高;茬口和施氮水平对各品质性状的变异系数影响分别为沉降值>湿面筋>蛋白质含量、沉降值>蛋白质含量>湿面筋.该项研究为专用小麦标准化生产提供了理论依据.     

构树形态特征及种子育苗技术

阐述了构树的形态特征,并从种子采集与处理、整地做床、播种、苗木管理等方面总结了种子育苗技术,以供参考。     

宁乡猪的毛色遗传及其与生产性状的相关

根据宁乡猪选育及专题调查资料研究表明,宁乡猪都有黑斑,这是由主基因所决定,而构成不同毛色类别的黑斑多少及着生部位,表现为多基因遗传,经子亲回归法估测,宁乡猪毛色的遗传力为0.3648(P<0.01).宁乡猪的银颈圈性状不同于汉普夏猪的白肩带,是黑、白斑分布系列中的一种类型。不同毛色类别的宁乡猪在后备猪生长发育、母猪体型及繁殖性状、肥猪的肥育和胴体性状方面没有明显不同,毛色类别与生产性状间的相关均不显著。因此,毛色只是品种特征和遗传稳定性的标志,与生产性能并无直接关系。     

Development of STS markers and QTL validation for common bacterial blight resistance in common bean

Common bacterial blight (CBB) of common bean ( Phaseolus vulgaris L.), is one of the major diseases that decrease yield and quality. A major quantitative trait locus (QTL) for CBB resistance from line XAN 159 was transferred into two bean lines, HR45 and HR67. Previous studies identified that two markers are linked to this QTL but the chromosome location was not consistent. To identify more tightly linked markers and to verify the chromosome location, 65 additional markers were mapped using 81 recombinant inbred lines (RILs) derived from a cross HR67 × OAC95-4. The QTL was mapped to a 13 cM region on chromosome 1 and defined by eight molecular markers that explained 25–52% of the phenotypic variation. Six tightly linked amplified fragment length polymorphism markers (0.6–9.7 cM from the QTL peak) were converted into seven sequence tagged site markers, three of which were mapped to this QTL. Five tightly linked markers were used to screen 907 F₂ plants derived from a cross HR45 × 'OAC Rex' and four of them were linked to each other within 4.2 cM. These markers may be useful in marker-assisted selection and map-based cloning of this major QTL.     

水稻空间诱变突变品系主要农艺经济性状分析

于2006年选用新稻11号干种子搭载实践八号返回式卫星进行处理,经多年南繁北育,对筛选出的10个高代突变品系农艺经济性状进行考察.结果表明,突变品系间产量存在显著差异,其中,XD11-6产量最高,比新稻11号(CK)增产8.52％.与对照相比,供试突变品系植株偏高.穗长变短,千粒质量偏高,精米率提高,生育期提前.简单和偏相关分析中分别有5对和2对性状相关性极显著.植株高度与穗长和千粒质量关系密切,而千粒质量更多受生育期的影响,表明空间诱变可望在株高、穗长、千粒质量、精米率及生育期等方面对水稻进行遗传改良.     

Non-iterative variance component estimation in QTL analysis

In variance component quantitative trait loci (QTL) analysis, a mixed model is used to detect the most likely chromosome position of a QTL. The putative QTL is included as a random effect and a method is needed to estimate the QTL variance. The standard estimation method used is an iterative method based on the restricted maximum likelihood (REML). In this paper, we present a novel non-iterative variance component estimation method. This method is based on Henderson's method 3, but relaxes the condition of unbiasedness. Two similar estimators were compared, which were developed from two different partitions of the sum of squares in Henderson's method 3. The approach was compared with REML on data from a European wild boar × domestic pig intercross. A meat quality trait was studied on chromosome 6 where a functional gene was known to be located. Both partitions resulted in estimated QTL variances close to the REML estimates. From the non-iterative estimates, we could also compute good approximations of the likelihood ratio curve on the studied chromosome.     

有氧运动训练对中华倒刺鲃幼鱼形态特征的影响

为了考察有氧运动训练对中华倒刺鲃幼鱼形态特征的影响,在(25±0.5)℃水温条件下,将大小相当的144尾中华倒刺鲃幼鱼(19.52±0.03)g,(10.29±0.02) cm轻度麻醉后随机分为4组:对照组、1 bl/s(体长/秒)训练组、2 bl/s训练组和4 bl/s训练组,在相应流速下训练8周(18 h/d)后,从各实验组中各随机挑选中华倒刺鲃,幼鱼12尾,测量并计算其形态特征参数.结果显示1 bl/s训练组尾柄侧面积显著大于对照组(p＜0.05);2 bl/s训练组的腹鳍前长、头长、叉长、尾柄侧面积及尾鳍面积等参数均显著大于对照组(p＜0.05);而4 bl/s训练组头高、体高、体高与体长比显著大于对照组(p＜0.05),其他形态参数较对照组无显著差异.研究结果表明有氧运动训练对中华倒刺鲃幼鱼的形态特征产生了显著影响;中华倒刺鲃幼鱼在不同流速下表现出的形态特征差异可能与其游泳速度和能量消耗相关.