Real-time RT-qPCR assay to detect sequences in the Piscine orthoreovirus-1 genome segment S1 associated with heart and skeletal muscle inflammation in Atlantic salmon

During the last decade, Piscine orthoreovirus was identified as the main causative agent of heart and skeletal muscle inflammation (HSMI) in Atlantic Salmon, Norway. A recent study showed that PRV-1 sequences from salmonid collected in North Atlantic Pacific Coast (NAPC) grouped separately from the Norwegian sequences found in Atlantic Salmon diagnosed with HSMI. Currently, the routine assay used to screen for PRV-1 in NAPC water and worldwide cannot differentiate between the two groups of PRV-1. Therefore, this study aimed at developing a real-time polymerase chain reaction (RT-qPCR) assay to target the PRV-1 genome segments specific for variants associated with HSMI. The assay was optimized and tested against 71 tissue samples collected from different regions including Norway, Chile and both coast of Canada and different hosts farmed Atlantic Salmon, wild Coho Salmon and escaped Atlantic Salmon collected in British Columbia, West Coast of Canada. This assay has the potential to be used for screening salmonids and non-salmonids that may carry PRV-1 potentially causing HSMI.     

鸽新城疫的流行与防控

鸽新城疫是由新城疫病毒感染鸽群引起的传染病, 在世界各国鸽场均有流行。介绍了鸽新城疫流行情况及特点, 流行毒株的基因型、病毒的毒力、病毒的抗原特性, 提出在做好鸽场内生物安全控制和精细化管理基础上, 使用市售新城疫疫苗进行合理免疫是鸽新城疫防控的关键。     

Cf-2/Rcr3pim番茄品系对南方根结线虫的抗性测定

Cf-2/Rcr3~(pim)基因型番茄不仅能够抵御番茄叶霉菌的侵染,而且对马铃薯金线虫的寄生也有一定的抑制效果。为挖掘根结线虫的新抗性资源,本研究采用室内人工接种法测定了Cf-0/Rcr3~(pim)、Cf-2/Rcr3-3和Cf-2/Rcr3~(pim)基因型番茄品系对南方根结线虫的抗感性。抗性评价结果显示,Cf-0/Rcr3~(pim)品系对南方根结线虫表现高感,Cf-2/Rcr3-3品系为中感,而Cf-2/Rcr3~(pim)品系则为感病。与Cf-0/Rcr3~(pim)和Cf-2/Rcr3-3基因型相比,Cf-2/Rcr3~(pim)基因型番茄品系虽然对南方根结线虫侵染的敏感性略低,但是不能阻止线虫在根系上的大量繁殖,不适于根结线虫的防控应用。     

基于BLUP和GGE双标图的林木多地点试验分析

【目的】建立基于无偏预测值(BLUP)与基因型主效加基因型-环境互作效应(GGE)双标图的分析模型,以提高林木多点试验数据分析的准确性。【方法】以火炬松36个基因型在6个试验地(S1~S6)的种子产量为基础数据,利用ASReml软件对实测数据进行空间变异结合因子分析法的模型拟合,以获取各地点下每个基因型的BLUP值;从试验地划分、试验地评估和林木基因型评估3个方面,对原始数据、BLUP数据进行GGE双标图分析与比较。【结果】BLUP数据具有明显的空间变异,比原始数据具有更高的产量变异解释能力;原始数据和BLUP数据的试验地分组结果一致,均分为2组,但BLUP数据的试验地点间的相关关系变弱;原始数据的理想试验地为地点S5,而BLUP数据为地点S1;原始数据和BLUP数据的最理想基因型均为21,但2种数据高产和稳产基因型的一致性比较低。【结论】基于BLUP与GGE双标图相结合的模型,可用于林木多点试验分析,其比原始数据的GGE双标图分析结果更为可靠。     

两种基因型菊芋幼苗对盐胁迫的生长及生理响应

采用盆栽方法研究不同浓度(2‰,4‰,6‰)中性复合盐对具有不同遗传背景的两种基因型菊芋幼苗(LZJ028有性繁殖能力强且营养品质高;LZJ017块茎产量高)生长和光合等生理特性的影响,探究不同遗传背景菊芋幼苗对盐胁迫的响应差异。结果表明:(1)当盐浓度为4‰和6‰时,两种基因型菊芋幼苗的株高、叶面积、冠幅和地上部分干物质和鲜物质积累(与对照相比)均下降,LZJ028基径、叶面积和地上部分干、鲜物质积累下降幅度(4.24%和6.26%,14.82%和29.67%,8.51%和19.68%,7.62%和22.38%)均显著低于LZJ017的降幅(9.78%和29.75%,58.33%和63.18%,15.77%和26.88%,40.62%和61.82%)。(2)随着盐浓度升高,两种基因型菊芋幼苗叶片的SOD活性、脯氨酸和可溶性糖含量均显著升高(如盐浓度为6‰时LZJ017和LZJ028的SOD活性比对照组升高了0.41倍和1.87倍;脯氨酸升高了8.26倍和42.92倍;可溶性糖含量升高了0.39倍和1.18倍),LZJ028的各指标升高幅度均较大。(3)盐浓度升高,两种基因型菊芋幼苗叶片净光合速率、蒸腾速率、气孔导度和叶绿素含量均降低,LZJ028净光合速率和气孔导度下降幅度均低于LZJ017;盐浓度升高,两种菊芋幼苗PSⅡ潜在活性和最大光化学效率也均下降,而初始荧光升高,如盐浓度为6‰时与对照相比LZJ028最大光化学效率和初始荧光变化幅度(10.53%和4.81%)低于LZJ017的变化幅度(43.04%和52.73%)。研究表明,盐胁迫主要抑制两种基因型菊芋叶片PSⅡ活性和碳水代谢速率进而抑制其生长,二者均通过提高保护酶SOD活性、增加渗透调节物质等策略缓解盐胁迫造成的伤害;LZJ028较耐盐,LZJ017对盐较敏感。     

The Tolerance Index and Translocation Factor were Used to Identify the Barley Genotypes with High Arsenic Stress Tolerance

Ninety-four barley genotypes were used to investigate the genotypic differences in arsenic (As) uptake and translocation and their relationships with As tolerance index (TI) and translocation factor (TF). Two As treatments (300 µM and 500 µM) were applied in the initial screening and the confirmatory experiments, respectively. The results showed significant (p < 0.05) differences in tissue biomass, shoot height, root length, As TI and TF among genotypes. Based on As TI, 11 barley genotypes were selected and divided into 3 groups, i.e. tolerant, mildly tolerant and sensitive. There was more As uptake in the roots of the As tolerant genotypes, while the As sensitive genotypes contained more As in shoots, which was further proved by the greater TF. Significantly negative correlation was observed between shoot and root As concentration. The results showed that As tolerant genotypes are able to restrict the upward movement of As, thus developing their tolerance.     

红花羟基黄色素A含量与花色相关性及其品种间的差异评价

探讨80个红花品种羟基黄色素A含量(HSYA)差异及其与花色的相关性,评价不同红花品种间的HSYA和花色的差别。以来源于不同产地的80份红花品种为试验材料,用高效液相色谱仪和Hunter Lab Easy Match?QC4.41型色差仪分析红花HSYA和花色差异。结果表明:不同基因型红花HSYA差异显著,变异幅度为0.05~14.99 mg/g,相差近288倍,平均为11.36 mg/g。在所有供试材料中,有43个红花品种的HSYA高于平均值。不同地理来源红花品种的HSYA差异较大,欧洲红花品种的HSYA高于亚洲和非洲;中国红花的HSYA高于土耳其、印度和肯尼亚等。视觉法将80份红花分为4个花色型,红色型红花HSYA高于橘色、黄色和白色型红花。白色、黄色、橘色和红色型红花的L分别为50.99、36.22、33.51和33.13,a分别为6.37、21.32、26.80和27.66,b分别为50.99、21.32、33.80和32.65。不同红花品种花色与L、a和b值呈显著正相关;黄色型和橘色型红花的HSYA与a值、色调值和色光值呈显著正相关;红色型红花HSYA与a值、b值和色光值呈显著正相关,表明a值越高,颜色越偏红,b值越高,颜色越偏橙。     

Screening of diverse cassava genotypes based on nitrogen uptake efficiency and yield

As one of the top three tuber crops of the world, cassava is a staple food and feed crop for tropical and subtropical regions. Because of its high drought resistance and tolerance to nutrient deficiency, cassava is usually cultivated on hilly areas that are nutrient-poor. Nitrogen(N) is one of the significant factors affecting cassava yield. A double factorial(N level×genotypes) split-plot field experiment was conducted to analyze differences in yield and N accumulation of 25 cassava genotypes under low-N conditions to screen for cassava genotypes with high-N efficiency. The two-year field experiment showed that cassava yield and N accumulation are determined by specific genotypes, soil N levels, and year. Among these factors, soil N levels are the main factors that are responsible for differences in cassava yield. When yield and relative N accumulation under low-N conditions were used as screening markers, we identified an efficient and responsive genotype(SC10), and two inefficient and non-responsive genotypes(SC205 and GR5). The efficient and responsive genotype and the inefficient and non-responsive genotype can be used as study materials to further reveal the mechanisms for high-N efficiency in cassava.     

苗期甘蔗氮高效基因型评价指标的筛选

本研究通过低氮压力选择,筛选出甘蔗氮高效种质,分析影响甘蔗氮高效的重要指标,为甘蔗氮高效育种及栽培提供理论依据。以58份甘蔗种质资源为材料,在苗期采用正常供氮（2 mmol/L N）和低氮（0.2 mmol/L N）处理,分析甘蔗植株形态、干重及氮素在各器官中累积分配的特征。通过主成分分析方法筛选影响甘蔗氮高效利用的重要指标,通过聚类分析对58份种质进行聚类。结果表明,低氮（0.2 mmol/L N）处理可以明显从植物形态区分不同种质的氮利用差异,58份种质低氮条件下的干重范围为0.64~14.75 g/株,氮累积量为5.53~63.00 mg/株,氮利用率范围为115.40~279.30 g/g。对低氮压力下甘蔗干重及氮累积等25个指标进行主成分分析后,提取出4个主要成分,总贡献率为92.35%。通过高、低氮条件下与氮利用效率有关的氮转移系数及基因潜力等19个指标分析后提取出5个主成分,总贡献率为82.21%。影响甘蔗氮高效的重要指标有甘蔗的干重（全株、叶、根）、氮累积量（全株、叶、茎）、氮利用率（全株、叶）、叶的相对氮利用率、茎的基因潜力、茎的相对干物质量和茎的相对氮累积量。经聚类分析后初步将58份甘蔗种质分为氮高效基因型、偏氮高效基因型、偏氮低效基因型和氮低效基因型。     

Individual polyphenolic profiles and antioxidant activity in sorghum grains are influenced by very low and high solar UV radiation and genotype

Sorghum is becoming more widely recognised around the world as a valuable crop for its polyphenol antioxidant health-promoting properties and adaptation to harsh environments. The antioxidant capacity of diverse polyphenols in sorghum grain can vary with climatic conditions and genotype. To explore this further, the potential role of UV radiation on the profile and concentration of polyphenols was investigated in six diverse sorghum genotypes in a controlled environment facility using natural UV and visible radiation under either UV-transmitting or UV-blocking treatments. The polyphenol content and antioxidant activity were significantly reduced under the UV-blocking treatment, with contents of individual polyphenols differing among the genotypes. This information is valuable for sorghum breeders enabling them to select genotypes and UV growth conditions to produce sorghum grain with target levels of polyphenols and antioxidant capacity for human foods to meet the nutritional and health needs of different consumers.