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91.
旨在将整合元共祖的一步法(single-step genomic best linear unbiased prediction with metafounders,MF-SSGBLUP)应用到基因组联合育种中,并与其他经典基因组选择方法进行比较分析。本研究使用QMSim软件模拟3个系谱相互独立的奶牛群体;分别使用广义最小二乘法(generalized least squares,GLS)和原始方法(naïve,NAI)估计不同群体间的祖先关系矩阵Γ;将MF-SSGBLUP、SSGBLUP和BLUP用于3个模拟群体的联合育种,评估各方法在遗传参数和育种值估计方面的差异。在不同遗传力下,GLS所得的Γ矩阵在对角线元素上略低于NAI法,在非对角线元素上没有明显差异,且基因组关系矩阵与基于元共祖构建的亲缘关系矩阵对角线元素相关系数(0.750~0.775)高于基因组关系矩阵与传统的亲缘关系矩阵相关系数(0.508~0.572)。MF-SSGBLUP遗传力估计值(0.138、0.140、0.297和0.298)与当代群体遗传力(0.107和0.296)的偏差小于其余两种方法(0.145、0.173、0.273和0.340),且MF-SSGBLUP估计育种值准确性(0.888~0.908)高于SSGBLUP法(0.863~0.876)和BLUP法(0.854~0.871)。表明,MF-SSGBLUP的遗传参数估计值无偏性更好,估计育种值准确性更高。根据上述模拟数据结果表明,在联合育种中,整合元共祖的基因组选择方法优于其他经典基因组选择方法。 相似文献
92.
摘要:为了明确红阳猕猴桃褐斑病主要病原菌及适宜的防治药剂,采集贵州省水城区红阳猕猴桃褐斑病的标样,通过组织分离、纯化,致病性检测,形态学观察,分子检测及系统发育分析确定病原菌种类,并采用菌丝生长速率法测定6种药剂对该病原菌生长的抑菌效果。结果显示:分离纯化得到的病原菌的形态特[收稿日期:
基金项目:贵州省科研机构创新能力建设项目(黔科合服企[2019]4004);贵州科学院青年基金(黔科院J字[2021]21号);贵州省科技计划项目(黔科合支撑[2021]一般234)
作者简介:苏文文(1992-),女,河南灵宝人,硕士,主要从事植物病理学研究。E-mail:275272042@qq.com;*为通讯作者:李苇洁,女,研究员,硕士,主要从事猕猴桃栽培和育种研究,E-mail:lwj024333@163.com]征与多主棒孢菌(Corynespora cassiicola)形态特征相似,将分离菌株rDNA–ITS序列与GenBank中相关菌株的ITS序列进行同源性比对,发现该菌株与黄瓜多主棒孢霉菌的相似性达到96%以上。室内药剂筛选结果表明:50%多菌灵可湿性粉剂对病原菌的抑制效果最好,最低浓度可抑制菌丝生长,其次为40%戊唑醇悬浮剂、80%乙蒜素乳油、30%吡唑嘧菌酯乳油和80%代森锰锌可湿性粉剂的抑菌效果较好,EC50分别为0.0002 mg/L、 0.0743 mg/L、0.0871 mg/L和0.5025mg/L。红阳猕猴桃褐斑病主要由多主棒孢菌(Corynespora cassiicola)侵染引起,以上5种药剂均可作为防治红阳猕猴桃褐斑病的有效药剂。 相似文献
93.
94.
Hessian fly [Mayetiola destructor (Say)] is one of the major insect pests of wheat (Triticum aestivum L.) worldwide. Hessian fly resistance gene H9 was previously reported to condition resistance to Hessian fly biotype L that is prevalent in many wheat‐growing areas of eastern USA and an RAPD marker, OPO051000, linked to H9 in wheat was developed using wheat near‐isogenic lines (NILs). However, marker‐assisted selection (MAS) with RAPD markers is not always feasible. One of the objectives in this study was to convert an RAPD marker linked to the gene H9 into a sequence characterized amplified region (SCAR) marker to facilitate MAS and to map H9 in the wheat genome. The RAPD fragment from OPO051000 was cloned, sequenced, and converted into a SCAR marker SOPO05909, whose linkage relationship with H9 was subsequently confirmed in two F2 populations segregating for H9. Linkage analysis identified one sequence tagged site (STS) marker, STS‐Pm3, and the eight microsatellite markers Xbarc263, Xcfa2153, Xpsp2999, Xgwm136, Xgdm33, Xcnl76, Xcnl117 and Xwmc24 near the H9 locus on the distal region of the short arm of chromosome 1A, contrary to the previously reported location of H9 on chromosome 5A. Locus Xbarc263 was 1.2 cM distal to H9, which itself was 1.7 cM proximal to loci Xcfa2153, Xpsp2999 and Xgwm136. The loci Xgwm136, Xcfa2153 and SOPO05909 were shown to be specific to H9 and not diagnostic to several other Hessian fly resistance genes, and therefore should be useful for pyramiding H9 with other Hessian fly resistance genes in a single genotype. 相似文献
95.
Summary The development and applications of molecular markers to hemp breeding are recent, dating back only to the mid-1990s. The main achievements in this field are reviewed. The analysis of Cannabis germplasm by RAPD, AFLP and microsatellites is discussed, with its consequence for the still debated species concept in Cannabis. DNA-based markers have also been exploited in the field of forensic science, in an attempt to discriminate licit from illicit crop. The main applications of the molecular markers to the breeding, however, have been achieved with the development of markers closely linked to the male sex and to some of the most relevant chemotypes. Active research is carried out by several groups in the field of identification and characterization of the genes involved in fiber quality and quantity, and in the determination of monoecy, another very important target of hemp breeding. Besides, markers associated to new, potentially useful chemotypes are being developed, for the marker-assisted breeding of pharmaceutical Cannabis. 相似文献
96.
Development of cytoplasmic male sterile 《分子植物育种》2007,5(2):215-216
Development of cytoplasmic male sterile (CMS) lines with elongated uppermost internode (EUI) trait provides a genetic option to eliminate the use of GA3 in hybrid rice. During the past two decades, extensive work has been carried out on the subject that resulted in identification of several mutants with EUI trait for use in developing cytoplasmic/thermo-sensitive genic male-sterile lines with complete panicle exsertion (Okuno and Kawai, 1978; Rutger and Carnahan, 1981; Shen et al., 1987; Yang et al., 2000; 2002; Gangashetti et al., 2004). Two recessive genes (eui-1 and eui-2) mapped on chromosome 5 and 10 respectively have so far been reported to control the internode elongation in rice (Librojo and Khush, 1986; Yang et al., 2001; Ma et al., 2004). Considerable progress has been made in China in exploiting 'eur gene for development of hybrid rice parental lines (Yang et al., 2000; 2002; Zhang et al., 2002). 相似文献
97.
Frew Mekbib 《Euphytica》2003,130(2):147-153
An experiment was undertaken to determine the stability of seed yield in 21 common bean genotypes representing three growth
habits. Seven genotypes in each growth habit (determinate bush, indeterminate bush and indeterminate prostrate) were evaluated
in replicated trials at three locations for three years under rain fed conditions in Ethiopia. A combined analysis of variance,
stability statistics and rank correlations among stability statistics and yield-stability statistic were determined. The genotypes
differed significantly for seed yield and genotype × environment (year by location) interaction (GE). The different stability
statistics namely Type1, Type 2 and Type 3 measured the different aspects of stability. This was substantiated by rank correlation
coefficient. There were strong rank correlations among Si
2d, Wi
2,σi
2 and Si
2, where as there was weak correlation between biand Ri
2, Si
2d, Wi
2, σi
2 and Si
2. R2 was significantly and negatively correlated with Wi
2, σi
2 and Si
2. σi
2 is significantly correlated with Wi
2.Yield is significantly correlated with bi and Ri
2.None of the statistics per se was useful for selecting high yielding and stable genotypes except the YS(yield-stability statistic). Most of the high yielding
genotypes were relatively stable. Of the 21 genotypes, only 11genotypes were selected for their high yielding and stable performance.
Genotypes with growth habit III and I (in determinate prostrate and determinate bush) were generally more stable than in determinate
bush.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
98.
Luciana Rossini Pinto Maria Lucia Carneiro Vieira Cláudio Lopes de Souza Jr Anete Pereira de Souza 《Euphytica》2003,134(3):277-286
BR-105 and BR-106 are important tropical maize populations, which were submitted to a high-intensity reciprocal recurrent
selection, generating the IG-3 and IG-4synthetics. Using 30-microsatellite loci,we measured and compared the genetic diversity
of these populations and their synthetics. The populations did not differ significantly regarding the amount of genetic diversity.
As a consequence of selection, genetic variability losses, in terms of mean number of alleles per locus,proportion of polymorphic
loci, and gene diversity did occur and were greater in the synthetic IG-3 than IG-4. In the synthetics, the number of loci
in adherence to Hardy-Weinberg proportions was superior to that observed in the populations. The Wright's mean fixation index
was higher than the mean value expected for outcrossing species (5%) indicating as light excess of homozygotic individuals
in both populations. The genetic distances confirmed the favourable effects of one cycle of recurrent selection, as the synthetics
became more isolated in comparison to the original populations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
99.
100.
Evaluation of resistance to Fusarium head blight in indigenous Japanese species of Agropyron (Elymus) 总被引:2,自引:0,他引:2
Tomohiro Ban 《Euphytica》1997,95(1):39-44
General (GSI) and specific (SSI) selection indices were constructed for three open-mating populations of sugarcane (Saccharum
spp.) seedlings and their ratoon stages. Though specific indices were found to be the most effective in improving mean brix
yield in their own source populations, but the GSI was better to SSI in other populations as indicated by higher mean values
and more number of superior clones at selection and evaluation stages. This indicated the wider applicability of the GSI over
SSI. Inspite of better expected genetic advance through GSI in ratoon crop, the actual gain in brix yield attained, through
GSI, was better in seedlings.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献