A proposal for enhanced EU herbage VCU and DUS testing procedures

Herbage production is regarded as having environment-friendly credentials. However, as the ruminant production it supports is facing major challenges on sustainability, environmental footprint and human health concerns, EU herbage cultivar testing must contribute to the solutions. Before new cultivars can be sold in a member state (MS) and gain EU-wide marketing, they must pass official tests to prove they are both novel (distinct, uniform and stable, DUS) with improved value for cultivation and use (VCU). Herbage species present specific challenges, as their allogamy imposes a wide within-cultivar variation that adds complexity to DUS tests and their “value” is only realized in ruminant produce. Current VCU systems measure production, chemical composition and disease/stress tolerances, often on large numbers of candidate cultivars, but prohibitive labour costs and logistics mean that animal intake, ruminant output or environmental benefits cannot be measured directly. Furthermore, some candidate cultivars with proven superior VCU fail DUS even though the non-distinct comparison is with a significantly lower performing registered cultivar. To resolve these problem cases, a “vmDUS” distinctness tool is proposed, which uses molecular markers but conforms to UPOV-declared principles. A short overview of current grassland research shows smart proxy measures of animal value can easily and quickly be adopted into an integrated pan-European (EU-VCU) test network. The proposed EU-VCU scheme will reallocate test resources to conduct these additional tests by placing MS in data sharing collaborations, while retaining their national listing authority. The benefits to all stakeholders from adopting these new testing procedures are considered.     

小白菜自交不亲和性相关基因的分子标记开发

以自交亲和系WS-199和自交不亲和系WS-85为亲本杂交获得的F_2分离群体为供试材料,采用BSA法结合SNP芯片技术,筛选出与自交不亲和性相关的SNP标记,并将SNP差异位点序列信息与白菜基因组序列进行比对分析,并进一步开发SSR标记,共获得了与自交不亲和性相关的SSR分子标记BrA1-2、BrA1-3和BrA1-14,为分子标记辅助自交不亲和性杂交种生产提供技术支持。     

Development and Application of Cotton InDel Markers Based on High Throughput Sequencing

[Objective] Dimorphic InDel markers can be used for cotton variety identification and purity detection, to improve the accuracy and efficiency of cotton seed testing, and to play a role in molecular breeding of cotton. [Method] Based on the whole genome sequencing of 121 cotton varieties from different sources, the InDel markers with high polymorphism were developed according to polymorphism information content(PIC) and were applied in the genetic distance analysis and cluster analysis by using 66 cotton varieties in China. [Result] Totally 10 967 InDel were identified based on the next generation sequencing data of 121 cotton varieties. Among the 85 pairs of InDel primers synthesized, 64 were selected including 35 from At group and 29 from Dt group. The minimum average allelic frequency(MAF) of At and Dt chromosomes were 0.45 and 0.32, respectively, while the PIC were 0.49 and 0.40, respectively. The genetic distances of the 66 cotton varieties ranged from 0.04 to 0.65 centimorgan (cM), with an average of 0.39 cM. The two varieties with the largest genetic distance were Simian 3 and CCRI 36, and the two varieties with the smallest genetic distance were Xumian 18 and Xuza 3. [Conclusion] The 64 cotton dimorphic InDel markers can effectively reveal the relationships among varieties based on the genetic distance, and distinguish cotton varieties from different sources, which has certain theoretical significance and application value.     

Genetic analysis and QTL mapping of growth period traits and plant height traits in soybean recombinant inbred lines from Dongnong 47 × PI 317334-B

High and stable yield is the main goal of soybean genetic improvement. In this study, association analysis was used to detect the quantitative trait loci (QTL) for the plant height, and soybean growth period using 182 SSR markers in the RIL population of 136 F_4:8 lines, which developed from a cross between photoperiod-insensitive cultivar ‘Dongnong 47’ and photoperiod-sensitive variety PI317334–B. The results showed that 33 QTLs related to soybean growth period and plant height traits were detected by compound interval mapping, and were located on 12 linkage groups including N, C1, C2, J, D1a, B2, E, G, A2, O, L, I, with the contribution rate of 7.85–33.84%. These QTL loci and linkage markers related to soybean photoperiod sensitivity, would be helpful to identify key genes that control soybean photoperiod sensitivity, and provide an important basis for the breeding of new photoperiod-insensitive soybean varieties based on molecular design breeding.     

Cross‐linked polyacrylates in post‐mining substrates: persistence and effects on plant growth

Application of hydrophilic polymers composed of cross‐linked polyacrylate can improve soil water‐holding capacity and accelerate the restoration of post‐mining substrates. In this work, we studied the persistence of a polyacrylate polymer incorporated into a soil and its impact on plant nutrients at a reclamation site of former lignite mining in Lusatia (Germany). In contrast to autumn application, the incorporation of the polymer enhanced the sequestration of plant‐derived carbon in the soil, which was reflected by a significant increase in the concentration of a lignin marker. Attenuated total reflexion–Fourier transform infrared spectra (ATR‐FTIR) and total elemental contents in the applied polymer suggested an intensive cation exchange between the polymer framework and the soil‐forming substrate. In addition, there was an enrichment of carbonaceous material, which seems to reduce the swelling and thus the water‐holding capacity of the cross‐linked polyacrylate. Conversely, this process protected the polymer structure from rapid decomposition.     

簇毛麦6VS特异转录序列P21461及P33259的获得及其分子标记在鉴定小麦-簇毛麦抗白粉病育种材料中的应用

簇毛麦6V#2S和6V#4S染色体臂分别携带抗白粉病基因Pm21和Pm V,在与小麦的杂种后代中,抗病基因与外源染色体臂共分离。开发鉴定2条外源染色体臂间多态性的序列,尤其是遗传信息相对缺乏的6V#4S染色体臂的序列,对于其在遗传与育种上的应用具有重要意义。本研究以携带6V#4S·6DL染色体的小麦易位系Pm97033及感病小麦亲本宛7107接种白粉菌的叶片转录组数据为资源,通过差异基因筛选、共线性分析、簇毛麦基因组扩增及测序验证的方法,鉴定出来自6V#4S的表达序列P21461和P33259,其中基于P21461序列设计的引物P461-5在簇毛麦6V#2S和6V#4S染色体臂的扩增产物具有30 bp的In Del和4 nt的多态性。用该引物转化的标记P461-5a可以鉴定抗白粉病小麦品种和高代品系所含的外源染色体,显示其在簇毛麦抗源鉴别和小麦抗病育种辅助选择中潜在的应用价值。根据P33259开发的标记P259-1可以对含有6V#4S染色体臂的材料进行特异扩增,但对6V#2S·6AL易位染色体没有扩增产物,因此P259-1可作为6V#4S·6DL易位染色体的特异分子标记。q RT-PCR分析结果显示,P21461的表达不受白粉菌诱导,而P33259在接菌后12 h和24 h的转录水平比接菌前提高约2倍,推测其可能参与Pm97033与白粉菌的早期互作。     

棉花单核苷酸多态性标记研究进展

单核苷酸多态性标记已在农作物研究中得到广泛应用并取得重大进展。为了便利棉花SNP(Single nucleotide polymorphism)标记的研究和应用,介绍了利用基因芯片、简化基因组测序、重测序等在棉花中开发SNP标记的方法 ,综述了SNP标记在棉花遗传图谱构建、数量位点的定位和分子标记辅助育种、基因组测序以及系统进化等研究中的应用。并对异源四倍体棉花中SNP标记开发时,同源序列位点和部分同源序列位点上的SNP标记辨别问题进行了系统探讨,对其快捷的开发、检测方式和在数量基因定位中的应用前景进行了展望。     

绵羊(ATAG)n四碱基微卫星位点的筛选及其在亲子鉴定中的应用

本试验旨在筛选绵羊高度多态性四碱基微卫星遗传标记,建立适用于绵羊亲子关系鉴定的实验体系。试验以小尾寒羊为主要研究对象,从已有的绵羊参考基因组序列出发,基于全基因组序列筛选法共筛选出53个（ATAG）_n四碱基重复微卫星位点,然后通过基因分型数据共筛选出30个扩增效果好、多态信息含量（PIC）丰富的四碱基重复微卫星位点;30个位点的基因分型结果表明,共扩增出253个等位基因,平均等位基因数为8.433,等位基因数均>5,多态信息含量在0.566~0.898,观测杂合度（Ho）范围在0.548~0.903,期望杂合度（He）范围在0.631~0.921,平均期望杂合度为0.776;哈代-温伯格平衡检验30个位点均处于遗传平衡状态。随后根据PCR的扩增效率从获得的30个多态性位点中筛选出22个微卫星位点用于亲权排除概率的计算,根据多态信息含量的大小由高到低依次增加位点数进行组合。结果表明,在两个亲本的基因型均未知的情况下,标记位点数为15个时,累积排除概率可达到99.99%,其中单个位点的第一非亲排除率（non-exclusion probability of the first parent,NE-1P）介于0.321~0.663之间。利用建立的亲子鉴定体系对16只具有系谱记录的小尾寒羊样本进行检测,结果共鉴定出4个具有高置信度的绵羊家系,鉴定结果与系谱记录完全一致。本试验为绵羊分子系谱的构建、亲子鉴定以及保障绵羊育种工作的正常开展奠定重要基础。     

松辽黑猪OAS1基因多态性及其与繁殖性状的关联分析

为探究寡腺苷酸合成酶1（oligoadenylate synthase 1,OAS1）基因多态性与松辽黑猪繁殖性状的关联性,试验选取130头松辽黑猪母猪为研究对象,利用Sanger直接测序法测序查找OAS1基因外显子1~8的SNP位点,使用SPSS 19.0软件分析OAS1基因SNP位点与松辽黑猪繁殖性状的关联性。结果显示,在松辽黑猪OAS1基因外显子2、3和6上共检测到33个突变位点;其中在外显子2的110 bp处存在1个SNP位点（G110C）,存在3种基因型：GG、GC和CC;在外显子3的176 bp处存在1个SNP位点（C176T）,存在3种基因型：CC、CT和TT;在外显子6的145 bp处存在1个SNP位点（C145T）,存在3种基因型：CC、CA和AA;在166 bp处存在1个SNP位点（G166A）,存在3种基因型：GG、GA和AA;在206 bp处存在1个SNP位点（A206G）,存在3种基因型：AA、AG和GG。卡方适合性检验结果显示,松辽黑猪OAS1基因G110C突变位点符合Hardy-Weinberg平衡状态,C176T、C145A、G166A和G206A位点均偏离Hardy-Weinberg平衡状态。群体遗传参数分析结果显示,各SNPs位点遗传杂合度均位于中等水平,为中度多态（0.25<PIC<0.5）。关联分析结果发现,G110C位点GC基因型个体总产仔数、产活仔数和断奶仔猪数均显著高于GG基因型个体（P<0.05）;C176T位点CT基因型个体断奶仔猪数显著高于CC基因型个体（P<0.05）;C145T位点CC基因型个体总产仔数和产活仔数均显著高于AA基因型个体（P<0.05）;G166A位点GA基因型个体断奶仔猪数显著高于GG基因型个体（P<0.05）;A206G位点GG基因型个体总产仔数和产活仔数显著高于AA基因型个体（P<0.05）。结果表明,OAS1基因外显子区存在突变位点,对松辽黑猪部分繁殖性状有显著性影响。     

Serum C-reactive protein concentration as an indicator of remission status in dogs with multicentric lymphoma

BACKGROUND: The acute-phase protein C-reactive protein (CRP) is used as a diagnostic and prognostic marker in humans with various neoplasias, including non-Hodgkin's lymphoma. OBJECTIVE: To evaluate if CRP could be used to detect different remission states in dogs with lymphoma. ANIMALS: Twenty-two dogs with untreated multicentric lymphoma. METHODS: Prospective observational study. Blood samples were collected at the time of diagnosis, before each chemotherapy session, and at follow-up visits, resulting in 287 serum samples. RESULTS: Before therapy, a statistically significant majority of the dogs (P = .0019) had CRP concentrations above the reference range (68%, 15/22). After achieving complete remission 90% (18/20) of the dogs had CRP concentrations within the reference range, and the difference in values before and after treatment was statistically significant (P < .001). CRP concentrations of dogs in complete remission (median, 1.91; range, 0.2-103) were significantly different (P = .031) from those of dogs with partial remission (median, 2.48; range, 0-89), stable disease (median, 1.77; range, 1.03-42.65), or progressive disease (median, 8.7; range, 0-82.5). There was profound variation of CRP measurements within each dog. CONCLUSIONS: CRP is useful in determining complete remission status after treatment with cytotoxic drugs. However, the individual variation between dogs means CRP concentration is not sufficiently different in other remission states to permit its use in monitoring progression of the disease. Greater reliability in determining remission status might be achieved by combining CRP concentration with other serum markers.