Effects of three methionine sources in diets on temporal B0AT1 and ASCT2 mRNA expression in different intestinal segments of cobia,Rachycentron canadum     

Yuanfa He  Shuyan Chi  Beiping Tan  Xiaohui Dong  Qihui Yang  Hongyu Liu  Shuang Zhang 《Journal of the World Aquaculture Society》2021,52(1):171-183

A 4‐week feeding trial was conducted using five groups of hybrid grouper (61.15 ± 0.15 g) to explore the potential effects of three methionine (Met) sources. Five isonitrogenous and isolipidic diets were formulated that included a fishmeal (FM) diet; nonsupplemented (NS) diet; or NS diets with the addition of the L‐methionine (L‐Met), DL‐methionine (DL‐Met), or coated Met (Co‐Met) to obtain the same Met level as the FM diet. Fish were randomly distributed into sea cages (30 fish per cage). Weight gain and specific growth rate in the DL‐Met group and FM group were significantly higher than those in all other groups (p < .05). In the proximal and distal intestines, of the 20 gene and time combinations (10 per gene), there were 14 combinations (70%) in which there were no significant differences in gene expression levels between the FM and DL‐Met groups (p > .05). The main reason for the same growth effect between the DL‐Met and FM groups may be attributed to the synchronized absorption at most time points after feeding, which had similar expression patterns of B⁰AT1 and ASCT2 of the proximal and distal intestines between two groups.  相似文献   

小麦4B染色体上LOX基因的等位变异及其区域分布     

王黎明  孔维玮  高华利  董普辉  闫雪芳  王春平  王洪刚  李兴锋 《作物杂志》2021,37(1):32-138

为了解中国不同麦区小麦种质资源籽粒脂肪氧化酶（lipoxygenase,LOX）活性相关基因TaLox-B1的差异和分布,利用小麦4B染色体上的功能标记LOX16和LOX18对7个麦区的436份种质资源进行分子检测。结果表明：在供试材料中共检测到3种TaLox-B1基因等位变异类型,分别为TaLox-B1a（与高LOX活性相关)、TaLox-B1b（与低LOX活性相关）和杂合型,其频率分别为19.0％、70.4％和10.6％。小麦LOX活性基因不同变异类型在各生态区的分布存在明显差异：基因型TaLox-B1a在黄淮冬麦区、北部冬麦区和长江中下游冬麦区分布较多,其比例分别为21.1%、19.8%和17.6%;基因型TaLox-B1b在西南冬麦区和长江中下游冬麦区分布较多,比例分别为87.9%、72.5%;杂合型仅存在于北部冬麦区、黄淮冬麦区与长江中下游冬麦区,比例分别为14.2%、12.4%和9.8%。利用标记LOX16和LOX18对53个自选高代品系进行分子检测,发现自选品系仅有TaLox-B1b与杂合型两种基因型,其中基因型TaLox-B1ab有32个,比例为60.4%。采用分子标记辅助选择,有利于快速鉴定小麦籽粒LOX活性,加速LOX的遗传改良和新品种选育。  相似文献   

马尾松叶表微生物多样性     

袁贵云  孙学广  郑炀  郭其强  丁贵杰 《森林与环境学报》2021,(3):318-324

为发掘对林木生长发育有利的优良微生物资源,并筛选适合叶表微生物的收集方法,以马尾松针叶为试验材料,分别用悬摇法和超声波法收集马尾松叶表微生物,用扩增子高通量测序技术、MUSCLE和Qiime软件研究马尾松叶表微生物的多样性。结果表明:扫描电镜观测结果显示,马尾松针叶表面定殖有大量微生物,包括真菌(菌丝及孢子)和细菌。扩增子高通量测序结果表明,马尾松叶表微生物物种丰富,包含细菌运算分类单位(OTUs)490个,真菌OTUs 1273个。马尾松叶表细菌以未分类的蓝细菌属(unidentified_Cyanobacteria)(36.53%)、未分类的拜叶林克氏菌属(unidentified_Beijerinckia)(28.60%)、鞘氨醇单胞菌属(Sphingomonas)(2.35%)为优势属;叶表真菌以枝孢属(Cladosporium)(2.45%)、拟盘多毛孢属(Pestalotiopsis)(0.92%)、无头孢菌属(Capnobotryella)(0.91%)为优势属。针对叶表细菌多样性的研究表明,悬摇法和超声波法均有较高的物种检出度;在叶表真菌多样性的研究中超声波法优于悬摇法,但超声波法样品间数据变异性较大,测定结果不稳定。  相似文献   

华北落叶松不同林分采种子代生长比较     

袁德水  魏巍  王桂鑫  冯铁成  黄威娜  王典娜  单楠 《河北林业科技》2020,(4):25-28

  相似文献   

毛竹内生拮抗细菌筛选及其16S rDNA鉴定     

袁宗胜 《安徽农学通报》2021,27(17):34-37,40

通过平板对峙法、滤纸片法、牛津杯法对6种食用菌病原菌的拮抗效果进行了初筛和复筛,并观察了细菌菌落表征性状;进行了16S rDNA序列分析.结果表明,初步筛选出了JL-B16、JL-A07、JL-B05、JL-B11、CT-B19、CT-B01、CT-B04-1、CT-A16等8株具有初步拮抗效果的内生细菌;复筛出4株具有较好拮抗效果的内生细菌,菌株编号分别是JL-B05、JL-B16、CT-A16、JL-A07;4株内生拮抗细菌菌株分属于2属3种,分别为芽孢杆菌属(Bacillus)和短杆菌属(Brevibacterium).该研究为内生拮抗细菌开发、防病微生物菌剂的制备及应用提供了资源.  相似文献   

Screening and Verification of Low Nitrogen Tolerant and Nitrogen Sensitive Cotton Germplasm     

Wang Zhun  Zhang Hengheng  Dong Qiang  Gui Huiping  Wang Xiangru  Pang Nianchang  Li Yongnian  Niu Jing  Jin Dingsha  Wang Sujie  Zhang Xiling  Song Meizhen 《棉花学报》2021,32(6):538-551

[Objective] The aim of this study is to evaluate nitrogen efficient cotton germplasms and improve nitrogen use efficiency. [Method] Eighty cotton germplasms were selected and evaluated in the hydroponic experiment under low (0.25 mmol·L^－1) and high (5 mmol·L^－1) nitrogen concentration. Different traits for screening were identified and nitrogen use efficiency types were classified. Field experiments were also performed for comparison and confirmation of the identified germplasms. [Result] The results showed that there were significant differences in the total plant dry matter, shoot nitrogen accumulation and nitrogen absorption efficiency in cotton germplasms at the two nitrogen levels. Based on coefficient of variation, principal component analysis and correlation, six traits including total plant dry matter, shoot dry matter, root dry matter, total nitrogen accumulation, shoot nitrogen accumulation and nitrogen absorption efficiency were used as screening indicators. According to the Heatmap clustering analysis and the nitrogen efficiency comprehensive index, two germplasms (Lu05R59 and CCRI 69) were identified as low nitrogen tolerant and nitrogen efficient, and two germplasms (Coker 201 and Xinluzhong 30) as low nitrogen sensitive and nitrogen inefficient. The results of field experiment were consistent with the results of the hydroponic culture at the seedling stage. [Conclusion] It was finally determined that Lu05R59 and CCRI 69 were the low nitrogen tolerant and nitrogen efficient germplasms, and Coker 201 and Xinluzhong 30 were low nitrogen sensitive and nitrogen inefficient germplasms. The results of these studies provide the possibility for screening and rapid identification of nitrogen use efficiency in cotton at the seedling stage, and provide the ideal materials and theoretical basis for further study of cotton nitrogen efficient.  相似文献   

同期排卵处理母牛体温和活动量变化规律及效果分析     

田宏志  陈晓丽  李欣  李茹意  王栋 《畜牧兽医学报》2020,51(7):1619-1627

为探究同期排卵处理母牛体温和活动量变化规律及不同同期排卵技术处理效果，指导同期排卵技术优化。本研究自动监测了18头20月龄左右同期排卵（GnRH-PG-GnRH）处理荷斯坦母牛和17头产后40~60 d预同期排卵（PG-PG-GnRH-PG-GnRH）处理荷斯坦母牛的体温和活动量，应用自动检测系统进行母牛发情监测。结果发现，同期排卵处理母牛发情时阴道温度平均升高（0.43±0.20）℃，持续（12.37±2.73）h；活动量平均升高（18.28±18.61）倍，持续（11.00±1.68）h；排卵时阴道温度平均下降（0.20±0.10）℃，持续（11.00±1.68）h。自动化发情监测显示，同期排卵处理母牛7头发情并排卵；预同期排卵母牛GnRH处理前全部发情排卵。两种同期排卵处理，虽可改变母牛性周期进程，促进母牛性周期同步化，但均难以使母牛性周期完全同步。因此，将同期排卵-定时输精和发情鉴定技术科学结合才能取得更好的繁殖效果。  相似文献   

工程设施技术在稻渔共作模式中的发展          下载免费PDF全文

袁虹  刘萍 《农业工程》2020,10(6):41-45

稻渔共作模式是一种继承传统农业中遵循自然协调、绿色生态的农业发展理念并以现代农业技术为指导的生态循环农业模式，该模式具有稳粮、促渔、增收、提质、环境友好和可持续发展等多种生态系统功能，但缺乏稻田生态理论研究及新的生态管理技术，且基础设施不足，与种养技术匹配设施缺乏。工程设施技术属于稻渔共作模式配套技术，决定稻渔共作模式的发展潜力。目前工程设备设施在稻渔共作模式中的应用普及程度低，尚未开发出与稻渔共作模式特点相匹配的专用设备。结合稻渔共作模式的发展历史和水平，对配套工程设施技术的发展进行分析。   相似文献   

秀珍菇原基形成相关基因PpFBD1的克隆与表达研究     

王伟科  宋吉玲  陆娜  袁卫东  闫静  陈观平 《浙江农业学报》2020,32(1):93

前期研究中通过对秀珍菇经低温诱导后不同发育阶段样本进行转录组测序及差异表达基因分析发现,ID为Cluster-6377.64510的基因(命名为PpFBD1)在原基形成前期的样本中高表达。为进一步了解分析其表达特性及功能,根据转录组测序结果设计特异性引物,利用RT-PCR技术从秀珍菇中克隆获得了该基因的cDNA全长。该基因由342个核苷酸组成,编码一个由113个氨基酸组成的蛋白,蛋白相对分子质量约11 ku。进化树分析显示,PpFBD1编码蛋白与糙皮侧耳hydrophobin1编码的疏水蛋白亲缘关系最近。Gene Ontology功能分析表明,PpFBD1主要参与真菌类细胞壁的合成。荧光定量RT-PCR检测显示,该基因在菌丝体经低温诱导后恢复至室温阶段(原基形成前期)表达量最高,这表明其可能参与调控秀珍菇原基形成过程。本研究结果为阐明秀珍菇原基形成机制提供参考。  相似文献   

两株新分离的APMV-I毒株感染SPF鸡的超微病理变化     

袁莉民  王永坤  朱国强  郁斌 《畜牧兽医学报》2004,35(5):565-569

将APMV-I鹅源分离株YG97鸡源分离株Y98和NDV强毒株F48E8感染SPF鸡，运用透射电镜观察该2株病毒分离株对机体细胞的影响，结果显示3株禽副黏病毒均引起机体肝、胰、脾、肾、心、胃、十二指肠和直肠等实质器官组织细胞的超微病变，如黏膜上皮细胞多处受损，表面微绒毛脱落；实质细胞核固缩、凝聚、凹陷、核多形性，线粒体嵴断裂、空泡样变、膜溶解，粗面内质网扩张、囊泡变，细胞浆的囊泡内及细胞浆内存在有囊膜的成熟病毒粒子等，但YG97和Y98对不同实质器官的组织细胞超微病变程度不一：胃、肝、胰、脾、肾超微病变比心脏的超微病变严重。电镜观察结果还表明：3株禽副黏病毒引起宿主细胞的超微病变有2种形式：坏死性病变和凋亡性病变。  相似文献