Microscopic detection of reactive oxygen species generation in the compatible and incompatible interactions of Alternaria alternata Japanese pear pathotype and host plants

 Reactive oxygen species (ROS) generation was examined in the interaction of Alternaria alternata Japanese pear pathotype and host plants using three methods: nitro blue tetrazolium (NBT) method for microscopic detection of O₂ ⁻, diaminobenzidine (DAB) methods for microscopic detection of H₂O₂, and cerium chloride methods for ultrastructural detection of H₂O₂. ROS generation was detected by NBT and DAB methods at appressoria on leaves of susceptible cultivars and heat-shocked leaves of resistant cultivars but not in leaves of resistant cultivars. Ultrastructural detection by the cerium chloride method identified ROS generation at cell walls of appressoria and penetration pegs in susceptible, resistant leaves and heat-shocked leaves. These differences in the ultrastructural and microscopic data in resistant areas were due to the restriction of ROS generation in limited areas, the side facing the plant surface, of appressoria and penetration pegs. Therefore, ROS generation was apparently induced regardless of the resistance or susceptibility of the cultivar with the difference being in the volumes generated. After evaluating the pathological role of ROS generation in fungal structures, such generation was found to be associated with early penetration of cell walls in pear plants. Additionally, ROS generation in plants was also found in degrading pectin layers near infected hyphae and in plasma membrane modification sites in susceptible leaves but not in resistant leaves. ROS generation in susceptible leaves might be accompanied with plasma membrane damage, although the role of ROS generation in the pectin layers is not clear. ROS generation in both fungal and plant cells during their interaction was likely associated with the expression of susceptibility. Received: June 3, 2002 / Accepted: July 31, 2002     

日本金龟子幼虫寄生蜂春黑小土蜂人工繁殖技术研究

以日本金龟子幼虫为繁殖寄主，对春黑小土蜂的人工繁殖技术进行了研究。试验结果表明：土蜂幼虫的发育历期，寄生三龄蛴螬的比二龄蛴螬的平均短3．76d；成茧率高1．87倍。二龄蛴螬繁殖的土蜂80％以上是雄性，三龄蛴螬繁殖的雌性蜂占60％以上。5％蜂蜜水和蔗糖水是成蜂较为理想的营养补充饲料。寄生作用率随接蜂数量的增加而减少。在土蜂产卵高峰期，种内干扰系数最高。单雌平均获卵量和获茧数随更换寄主频次的增加而增加，以每8h更换一次寄主最为适合。     

Questionnaire-based study on consumer requirements for beef quality in Japan

A questionnaire study examining Japanese consumers’ requirements for beef quality was carried out in April 2002 in Tsukuba, Ibaraki, Japan. Answers from 532 participants were used for the statistical analysis. Twenty questions about sensory properties, appearance, safety and freshness, production area, price, and other properties were prepared. The answers were applied to principal component analysis. Five principal components were obtained and defined, and the principle component scores were used to classify participants. The panels were classified into four groups profiled as ‘specific quality orientated’, ‘Wagyu (Japanese beef) orientated’, ‘safety and freshness orientated’ and ‘overall high quality orientated’. In addition, gender and age characteristics were different among the groups. Sensory properties did not affect the classification of respondents.     

刺参(Apostichopus japonicus)重要经济性状相关SNP标记的验证分析

本研究在前期构建的刺参(Apostichopus japonicus)高密度遗传连锁图谱和QTL分析的基础上,筛选出26个与体长、体重、体宽、棘刺总数、抗病力相关的SNP位点,设计出可用于HRM检测的SNP扩增引物13对。在扩大群体中利用HRM小片段法对这13个刺参重要经济性状相关的候选SNP位点进行分型和多态性检测,并结合扩大群体的相关性状数据进行了QTL位点验证。多态性结果显示,13个位点中有3个单态性位点,其余10个多态性位点中有3个位点为低等位多态性,7个位点为中等位多态性。10个多态性位点的最小等位基因频率(MAF)介于0.016(SNP113)~ 0.332(SNP160)之间,平均值为0.173;各位点的观测杂合度(Ho)介于0.031(SNP113)~0.818(SNP9)之间,平均值为0.433;期望杂合度(He)介于0.031(SNP113)~0.834(SNP9)之间,平均值为0.402;多态信息含量(PIC)介于0.030(SNP113)~0.393(SNP160)之间,平均为0.248,有6个位点偏离Hardy- Weinberg平衡。QTL验证结果表明,SNP40和SNP160位点为与生长(体长、体重、体宽)相关的位点,各位点的优势基因型分别为SNP40(CC)和SNP160(AA);SNP88、SNP112和SNP126这3个位点为与抗病力相关的位点,各位点的优势基因型为SNP88(CC)、SNP112(AA)和SNP126(TT)。基于这5个位点构建生长和抗病二倍型,发现二倍型K1(CC AA TT)抗病力最强,S1(CC AA)、S3(CC AC)在生长方面优势显著,相关研究结果可为分子标记辅助育种在生产中应用提供基础数据。     

3种不同体色刺参体壁营养成分的比较研究

本研究分别对青色、紫色和白色刺参(Apostichopus japonicus)体壁的营养成分,包括蛋白、脂肪、粗多糖、氨基酸组成、脂肪酸组成及微量元素进行了比较分析.结果显示,青色刺参蛋白含量显著低于紫色和白色刺参(P<0.05),脂肪含量三者无显著差异(P>0.05),青色刺参和紫色刺参的粗多糖含量高于白色刺参(P...     

低盐和高盐环境下刺参选育品系生长与摄食性能研究

为评价刺参(Apostichopus japonicus)耐盐品系选育效果,以G4、G5代刺参耐盐选育品系为研究对象,研究了其在低盐度和高盐度环境下的生长、摄食和消化生理的变化.结果显示,30 d实验期间,G4代和G5代2种规格选育刺参在不同盐度环境中的生长情况相似,在低盐环境中的末体重随着实验盐度的降低而下降,在高盐...     

饲料维生素C对急性降温后花鲈免疫、抗氧化及抗应激的影响

为研究饲料维生素C(Vc)对急性降温后花鲈(Lateolabrax maculatus)免疫、抗氧化及抗应激的影响,以含有不同水平Vc(6.85、46.90、88.24、167.43、329.21和658.69mg/kg)的饲料饲养花鲈56d后,进行急性降温(从33℃C水体转入27℃水体)处理24h和48h.结果显示,...     

种苗处理对麦冬生长的影响及其控病效果研究

为了明确种苗处理对麦冬生长的影响及其控病效果,指导麦冬优质安全生产.以川麦冬为供试材料,采用田间小区试验,研究了 6种药剂3种种苗处理方式对麦冬种苗成活、生长和产量的影响,以及对炭疽病、根腐病的控病效果.结果表明木霉T23制剂、多抗霉素和噁霉灵处理种苗,可显著提高麦冬种苗成活率,促进麦冬分蘖、增加块根数、使块根伸长增粗...     

刺参响应灿烂弧菌侵染差异microRNAs鉴定及靶基因分析

microRNA参与基因的转录后调控,在真核生物的生长发育、细胞分化和免疫防御等过程中发挥重要作用。刺参(Apostichopus japonicus)病害问题已成为产业发展的主要限制因素之一,而其病害发生的分子机制尚待进一步完善。本研究以刺参重大疾病“腐皮综合征”的重要致病原灿烂弧菌(Vibrios splendidus)为侵染菌株,通过人工侵染实验制备患病刺参样本,采用miRNA-seq技术对侵染组(PT16S)和对照组(PT10H)各3头刺参的体壁组织进行miRNA测序,通过相关生物信息学软件对miRNAs进行鉴定和分析,筛选差异表达miRNAs (DEmiRNAs)并预测其靶基因,构建关键调控途径的miRNA-mRNA调控网络。结果显示,PT10H组平均得到5 902 588条有效序列,194个已知miRNA和19个新的miRNA;PT16S组平均得到5 053 529条有效序列,182个已知miRNA和42个新的miRNA。对2组鉴定到的miRNA进行差异表达分析,共筛选到2个上调和11个下调的具有显著差异的DEmiRNAs (P≤0.05),上调的DEmiRNAs靶基因预测结合到3010个靶基因,注释到585个GO terms及24条信号通路(P≤0.05),下调的DEmiRNAs靶基因预测到19 072个靶基因,注释到514个GO terms以及22条信号通路(P≤0.05)。对筛选到的DEmiRNAs进行实时荧光定量PCR (qRT-PCR)验证,显示miRNA-seq与qRT-PCR的一致率达到70%。根据KEGG分析结果构建泛素介导的蛋白水解途径和Notch信号通路的miRNA-mRNA调控网络,结果显示,13个DEmiRNAs分别靶向结合134个与泛素介导的蛋白水解相关的mRNAs和109个与Notch信号通路相关的mRNAs,Aja-miR-184、Aja-miR-2478和Aja-miR-9277p等DEmiRNAs可能参与对Notch信号通路和对泛素介导的蛋白水解的调控。相关研究结果将为刺参疾病发生调控网络建立和机制解析提供依据。     

黄海北部辽宁近岸海域鳀产卵场分布特征及其影响因素

为掌握黄海北部辽宁近岸海域鳀(Engraulis japonicus)产卵场的分布特征及其关键环境因子,基于2021年4—12月开展的产卵场综合调查获取的鳀样品及其鱼卵密度数据,运用Garrison重心分布法阐释鳀产卵洄游分布特征及其主产卵期;通过基于Tweedie分布的广义可加模型(generalized additive model, GAM)的构建,分析主产卵期内鳀卵密度与同步获取的海水表层温度(SST)、海水表层盐度(SSS)、海水表层叶绿素浓度(Chla)、浮游动物丰度(Fd)、浮游植物丰度(Fz)和深度(Depth)等6个环境因子,以及时间(月份,Month)和空间(经纬度、Lon和Lat)因子之间关系,并识别主控因子。结果显示,海域内鳀产卵期较长,由4月持续至11月,5—8月为主产卵期,其中,5—6月为产卵盛期。鳀产卵场规模和位置时空变化明显,时空因子与鳀卵密度分布呈密切非线性相关(累积偏差解释率为48.1%),(SST, SSS) (18.7%)和Depth (5%)次之。鳀产卵期适温范围较广,产卵场分布表现出高温高盐(低温低盐)增效作用和高温低盐限制作用。产卵初期(4月),鳀产卵场规模和鱼卵密度均较低,产卵重心位于海洋岛东南侧深水区;盛期(5月底—6月初)在SST主导下,鳀产卵场规模和鱼卵密度均至年内最高值,核心产卵场位于石城岛–庄河河口一带海域;此后,随着辽南沿岸水系盐度的下降,高温低盐的抑制作用使SSS因素主导产卵鱼群避开沿岸海域,鳀产卵场迁移至外海深水区,7月后位于30~50 m等深线之间;9—10月鳀繁殖活动基本结束,10月鳀卵仅零星分布于调查海域,直至12月未有鳀卵采获。研究可为黄海北部辽宁近岸海域鳀产卵场研究及鳀资源合理开发利用提供参考依据。