我国柑橘全爪螨发生及防控研究概况

柑橘全爪螨Panonychus citri McGregor是柑橘上的重要害螨,严重影响柑橘产量和品质。我国作为柑橘生产第一大国,做好柑橘全爪螨的防控意义重大。研究其发生规律、防治技术、抗药性等是做好防控的重要环节。现阶段我国采取以化学防治为主,多种防治手段并存的综合防治策略,化学药剂防治由于其见效快、成本低、防治效果好,能及时的挽回经济损失,是当前我国防治柑橘全爪螨的最有力措施。但近年来柑橘全爪螨对各药剂的抗性发展迅速,因此为解决“3R”问题生物防治也成为我国研究的热点。除此之外,在柑橘全爪螨对各药剂均产生不同程度抗性的情况下,更应该致力于研究发展生物防治等其他绿色防控措施,并密切关注田间柑橘全爪螨抗性发展变化。本文综述了我国柑橘全爪螨发生因子、防治技术、抗药性等研究进展,并提出进一步的研究策略,为防治柑橘全爪螨提供一定的理论依据。     

桂林地区柑橘全爪螨对几种杀螨剂抗药性分析

为了解近期桂林地区柑橘全爪螨抗药性发展情况,本文采用浸叶法调查了柑橘全爪螨对几种杀螨剂的抗药性,结果表明,对尼索朗,柑橘全爪螨卵抗性倍数为中抗水平,若螨抗性为低抗水平,雌成螨敏感性降低水平;对四螨嗪,柑橘全爪螨卵、若螨、雌成螨均处于低抗水平;对阿维菌素,柑橘全爪螨卵为低抗水平阶段,若螨和雌成螨处于敏感性降低水平;对克螨特和乙螨唑,柑橘全爪螨卵、若螨、雌成螨均没有产生抗性。由于尼索朗、四螨嗪、乙螨唑同属螨虫生长抑制剂,而尼索朗和四螨嗪已出现抗性,可以考虑乙螨唑-阿维菌素-克螨特轮换使用。     

桂北地区柑橘全爪螨对6种药剂的抗药性测定

柑橘全爪螨(Panonychus citri McGregor)是柑橘上的重要害虫,目前主要通过化学药剂对其进行防治,但由于长期以来化学药剂的不合理使用使得其对不同杀螨剂产生了不同程度的抗性。通过对监测数据的分析能够更好的指导田间用药,为实际生产中柑橘全爪螨的防治与其抗药性治理提供理论依据。2021年采用叶碟浸渍法对广西桂林临桂区和灵川县两个柑橘全爪螨田间种群进行了抗药性测定。结果标明：桂林临桂、灵川两地柑橘全爪螨田间种群对乙唑螨腈、联苯肼酯、阿维菌素和乙螨唑均已产生高水平抗性(105.6-572.0倍);且对哒螨灵和螺螨酯也产生了中等水平抗性(44.8-96.2倍)。生产上应减少阿维菌素、联苯肼酯和乙螨唑的使用,应合理的进行复配,并结合其他防治措施进行综合防治,保障我国柑橘产量与品质。     

万州果园柑橘全爪螨对不同浓度杀螨剂敏感度比较2

试验选取最新8种杀螨剂进行柑橘全爪螨敏感度试验,结果表明：施药初期柑橘全爪螨敏感度最低的药剂是联苯菊酯乳油,但在后期对该药剂表现出一定的抗药性。害螨对螺螨酯悬浮剂和联苯肼酯悬浮剂的初始敏感度较高,但随着时间的延长,对该药剂越来越敏感。对于5%阿维菌素微囊悬浮剂、20%哒螨灵悬浮剂、20%乙螨唑悬浮剂、22.4%螺虫乙酯悬浮剂、50%丙溴磷乳油,害螨一直处于较为敏感的阶段,施药后30天的死亡率在98%以上,害螨还未对这几种药剂产生抗药性,是万州果园害螨防控的良好备选药剂。     

矿物油防治柑橘刺吸式害虫药效试验初报

药效试验表明,不同矿物油乳油对柑橘红蜡蚧和柑橘全爪螨有理想防效,97%矿物油乳油50倍液药后5天对红蜡蚧防效达85.30%,95%矿物油乳油50倍液药后5天对红蜡蚧防效达93.35%%,99%矿物油乳油150倍液对柑橘全爪螨药后3天、10天的防效分别达97.32%、94.44%;安全性高,对柑桔和天敌生物无不良影响;长期使用不会产生抗性。     

柑橘全爪螨环境相容性农药筛选

从257个柑橘全爪螨田间药效试验中筛选到17种比较好的药剂。对这些药剂的种类和作用特点、使用浓度、防治效果、速效性、持效期、防治技术要点进行了分析和总结,提出了柑橘全爪螨的防控以矿物油为主,其他药剂为辅的综合防治的观点,为绿色柑橘生产中叶螨的防控提供了理论基础。     

阿维菌素和螺螨酯对柑橘红蜘蛛的联合毒力

摘要 选阿维菌素和螺螨酯两种原药配制成不同比例的混剂,采用Potter喷雾法测定各自对柑橘全爪螨的室内联合毒力。结果表明,阿维菌素和螺螨酯不同配比的混剂对柑橘全爪螨有不同的复配效应,其中配比1:25混剂的共毒系数为117.23,表现为相加作用,配比1:5、1:10、1:15、1:20混剂的共毒系数分别为144.04、188.77、141.61、165.43,表现为增效作用,其中配比1:10混剂的共毒系数最大,具有最好的增效作用。     

柑桔全爪螨抗性分子机理研究取得重要进展

柑桔全爪螨又名柑桔红蜘蛛,是一种世界性害螨,在我国各柑桔产区为害特别严重。目前,化学防治仍是控制柑桔全爪螨最为有效的措施,但由于其个体小、世代多、繁殖力强,对药剂极易产生抗性。尽管柑桔全爪螨抗性极其严重,但确切的抗性分子机理仍不明确。     

乙螨唑对柑橘全爪螨的室内毒力测定

测定了乙螨唑等五种杀螨剂对柑橘全爪螨雌成螨、幼螨和卵的室内毒杀活性,结果表明,乙螨唑对柑橘全爪螨雌成螨、幼螨具有很高的触杀毒力, LC50值分别为41.3 ug/ml和22.5 ug/ml,不及阿维菌素毒力 （LC50值分别为9.4ug/ml和11.3ug/ml）;;乙螨唑对卵的毒杀活性是23.5ug/ml,是常用杀螨剂阿维菌素、尼索朗的1.6倍。此研究为乙螨唑在柑橘生产中的广泛使用提供了参考。     

单宁酸对豌豆蚜谷胱甘肽-S-转移酶活性与基因表达的影响

本研究通过测定单宁酸(2 g·L^-1)处理豌豆蚜(Acyrthosiphon pisum) 48 h后体内谷胱甘肽-S-转移酶(GST)活性以及不同组织GST基因转录水平的变化,以明确单宁酸对GST活性以及基因表达的影响。结果表明：豌豆蚜取食单宁酸(2 g·L^-1) 48 h后,GST活性下降。相比不处理对照,经单宁酸处理后,豌豆蚜头部有7个GST基因上调表达,其中ApGST104、ApGSTX1上调表达3倍左右;胸部有10个GST基因上调表达,其中ApGSTD6上调表达6.4倍;腹部有10个GST基因上调表达,其中ApGST101、ApGST105上调5倍左右;中肠有9个GST基因上调表达,其中ApPGST105上调表达3.2倍。从结果可以看出,单宁酸对豌豆蚜GST基因的表达产生了影响,部分GST基因显著上调表达(P <0.05),表明GST基因可能在豌豆蚜对单宁酸的代谢中发挥重要的作用。     

3种不同柑橘品种水杨酸处理前后对溃疡病的抗性分析

为了探明对溃疡病敏感度存在差异的金柑、甜橙和枳在水杨酸处理前后的抗病性差异,对3种柑橘材料进行外源水杨酸处理并进行溃疡病菌接种。结果表明,3种柑橘材料中,金柑对溃疡病抗性最高,其次为甜橙。枳对溃疡病的抗性最低,病害症状最显著且细菌增殖最快;经过水杨酸处理后3种柑橘材料对溃疡病的抗性都有不同程度的提高,死亡细胞数量减少、相对电导率含量降低、细菌数量也显著减少。进一步分析3种不同柑橘材料水杨酸处理中抗病基因的表达模式发现,金柑中NPR1、PAD4、PR1基因被显著诱导上调表达,且高于其余两种柑橘材料,表明金柑对溃疡病的高抗能力可能与其体内显著上调的抗病基因相关。     

Dual oxidase 2 and glutathione peroxidase gene expression are elevated in hyperimmunized sheep challenged with Haemonchus contortus

A sequential biopsy sampling method was used to investigate oxidant and antioxidant gene responses in resistant sheep challenged with Haemonchus contortus larvae or a sham saline challenge. The expression of key sheep oxidant and antioxidant producing genes were measured in sequential samples removed from the abomasums at days 0, 1, 2, 3, 5, 7 and 28 post challenge. Gene expression levels at each time point were compared to expression at day 0, and levels of the various genes were also correlated to other markers of infection including immune cell counts and cytokine gene expression. The early response to larval challenge infection in resistant animals was marked by a divergence of two groups of host oxidant producing genes: the dual oxidase group (DUOX2/DUOXA2) showing increases in expression to day 7, while members of the phagocytic NADPH oxidase (PHOX) group showed significant decreases in expression. The change in DUOX2 expression between days zero and seven, when host resistance to infection is mediated, was negatively correlated to final worm burden suggesting NADPH oxidase expression may play a role in parasite expulsion. Expression of the DUOX group oxidants was positively correlated to expression of the Th2 cytokine IL4. Changes in host antioxidant pathways between different members of the glutathione peroxidase family (intestinal and plasma GPX) and genes involved in glutathione metabolism were also observed. This first study of the putative roles of oxidant production by the dual oxidase group, antioxidant glutathione pathways, immune cell populations, and cytokine profiles, in the development of resistance to infection by hyperimmune sheep are discussed.     

赖氨酸对奶牛乳腺上皮细胞内乳脂肪合成相关基因和蛋白表达的影响

本试验旨在研究赖氨酸(Lys)对奶牛乳腺上皮细胞(BMECs)内乳脂肪合成相关基因和蛋白表达的影响,探讨Lys影响乳脂肪合成的机理。将第3代BMECs随机分为6组,每组6个重复,每个重复1个培养孔。各组培养基中Lys的浓度分别为0.5(基础培养基,对照)、1.0、2.0、4.0、8.0和16.0mmol/L,37℃、5%CO2培养48h后测定BMECs甘油三酯(TAG)含量、乳脂肪合成相关基因和蛋白的表达量。结果表明:BMECs内TAG含量(P=0.013)以及脂肪酸结合蛋白3(FABP3,P=0.001)、脂蛋白脂酶(LPL,P=0.096)、脂肪酸合成酶(FASN,P=0.003)、乙酰甘油磷酸脂酰转移酶6(AGPAT6,P=0.038)和甘油-3-磷酸酰基转移酶(GPAM,P=0.022)基因表达量对Lys呈显著或趋于显著的浓度依赖效应。FABP3基因表达量以2.0、4.0、8.0、16.0mmol/L组和LPL基因表达量以1.0、2.0、4.0、8.0、16.0 mmol/L组显著高于0.5mmol/L组(P0.05);FASN基因表达量以2.0mmol/L组最高,显著高于16.0mmol/L组(P0.05);硬脂酰辅酶A去饱和酶1(SCD1)基因表达量以2.0、4.0mmol/L组显著高于其他组(P0.05);磷脂酸磷酸酯酶1(LPIN1)、嗜乳脂蛋白亚家族1成员1(BTN1 A1)和黄嘌呤脱氢酶(XDH)基因表达量均以1.0、2.0、4.0、8.0mmol/L组显著高于0.5mmol/L组(P0.05);过氧化物酶体增殖物激活受体γ(PPARγ)基因及蛋白表达量均以2.0、4.0mmol/L组显著高于0.5和8.0、16.0mmol/L组(P0.05);固醇调节元件结合蛋白1(SREBP1)基因表达量以1.0、2.0、4.0mmol/L组显著高于其他组(P0.05),蛋白表达量以1.0 mmol/L组显著高于其他组(P0.05)。但高浓度Lys抑制AGPAT6和GPAM的基因表达,AGPAT6基因表达量以2.0、4.0、8.0、16.0mmol/L组显著低于0.5、1.0mmol/L组(P0.05),GPAM基因表达量以16.0mmol/L组显著低于0.5、1.0、2.0、4.0mmol/L组(P0.05)。可见,Lys对BMECs的乳脂肪合成具有显著的促进效果,但高浓度的Lys抑制了乳脂肪合成相关基因的表达。本试验条件下,培养基中Lys适宜浓度为2.0~4.0mmol/L。     

MyoD and Myf6 gene expression patterns in skeletal muscle during embryonic and posthatch development in the domestic duck (Anas platyrhynchos domestica)

The MyoD and Myf6 genes, which are muscle regulatory factors (MRFs), play major roles in muscle growth and development and initiate muscle fibre formation via the regulation of muscle‐specific gene translation. Therefore, MyoD and Myf6 are potential candidate genes for meat production traits in animals and poultry. The objective of this study was to evaluate MyoD and Myf6 gene expression patterns in the skeletal muscle during early developmental stage of ducks. Gene expression levels were detected using the quantitative RT‐PCR method in the breast muscle (BM) and leg muscle (LM) at embryonic days 13, 17, 21, 25, 27, as well as at 1 week posthatching in Gaoyou and Jinding ducks (Anas platyrhynchos domestica). The MyoD and Myf6 gene profiles in the two duck breeds were consistent during early development, and MyoD gene expression showed a ‘wave’ trend in BM and an approximate ‘anti‐√’ trend in LM. Myf6 gene expression in BM showed the highest level at embryonic day 21, which subsequently decreased, although remained relatively high, while levels at embryonic days 13, 17 and 21 were higher in LM. The results of correlation analysis showed that MyoD and Myf6 gene expression levels were more strongly correlated in LM than in BM in both duck breeds. These results indicated that different expression patterns of the MyoD and Myf6 genes in BM and LM may be related to muscle development and differentiation, suggesting that MyoD and Myf6 are integral to skeletal muscle development.     

4猪种Nramp1基因第6内含子多态性研究

天然抗性巨噬蛋白(Nramp)基因是与人、鼠的一些病原微生物的易感性和抗性有关的重要候选基因。为了研究猪Nramp1基因的多态性,利用PCR-RFLP技术检测了杜洛克、大白猪、长白猪和合作猪共270头个体Nramp1基因第6内含子NdeⅠ酶切位点多态性。结果表明,4个猪种群共检测到3种基因型(AA、AB和BB),其中AB基因型为杜洛克、大白猪和长白猪的优势基因型;AA基因型为合作猪的优势基因型。经卡方适合性检测,杜洛克、合作猪和长白猪处于Hardy-Weinberg平衡状态(P>0.05),大白猪处于Hardy-Weinberg不平衡状态。多态信息含量分析显示,Nramp1基因的第6内含子NdeⅠ酶切位点在各猪种表现出中度多态性。     

水牛ABCD基因家族生物信息学分析及ABCD1基因表达研究

为鉴定水牛ATP结合盒（ATP-binding cassette,ABC）转运蛋白D （ABCD）基因家族成员及其在水牛中的表达,本研究利用生物信息学对水牛ABCD基因家族的染色体定位、基因结构、保守结构域、蛋白理化性质进行分析,利用实时荧光定量PCR检测ABCD1基因在水牛各组织及不同泌乳期乳腺中的表达,并用3种激素处理水牛乳腺上皮细胞,检测激素对ABCD1基因表达的影响。结果显示,从水牛全基因组中共鉴定出9个ABCD家族基因,分别为ABCD1、ABCD2、ABCD3、ABCD4,其中ABCD4基因包含6个不同转录本（ABCD4X1-ABCD4X6）,ABCD1~ABCD4 4个基因分别位于X、4、6、11号染色体;序列分析发现,ABCD家族基因包含9~22个内含子,编码444~741个氨基酸,分子质量为49.63~83.41 ku,等电点为6.43~9.64;共找到ABC_membrane_2、Endonuclease_5、ABC_tran 3个ABCD家族基因所共有的功能基序。ABCD基因家族可分为4个亚族,系统进化树显示,ABCD基因高度保守。共线性分析表明,水牛和奶牛之间存在7对直系同源的ABCD家族基因。不同组织定量表达结果表明,ABCD1基因在水牛15个组织中均有表达,其中在脂肪组织中表达量最高。不同泌乳时期的乳腺组织定量表达结果显示,ABCD1基因在50 d表达量达到最高,整个泌乳期呈现低-高-低表达模式。用不同浓度催乳素、雌二醇、孕酮分别处理水牛乳腺细胞,当催乳素、雌二醇和孕酮浓度分别达到2.0、0.3和4.5 μg/mL以上时,ABCD1基因表达量显著高于对照组。结果表明,水牛ABCD基因家族包含9个基因,其中ABCD1基因参与泌乳调控,本研究为进一步探讨ABCD家族基因在水牛乳腺中的功能提供了参考依据。     

Avian influenza virus infection induces differential expression of genes in chicken kidney

The pathogenic process of highly pathogenic avian influenza virus (HPAIV) infection is poorly understood. To explore the differential expression of kidney genes as a result of HPAIV infection, two cDNA libraries were constructed from uninfected and infected kidneys by suppression subtractive hybridization (SSH). Fifteen genes including IFN-stimulated genes (ISG12), lymphocyte antigen 6 complex locus E gene (LY6E), matrix Gla protein gene (MGP), lysozyme gene, haemopoiesis related membrane protein 1 gene, KIAA1259, MGC68696, G6pc-prov protein gene (G6PC), MGC4504, alcohol dehydrogenase gene (ADH), glutathione S-transferase gene (GST), sodium-dependent high-affinity dicarboxylate transporter gene (SDCT), Synaptotagmin XV (SytXV) and two novel genes were found significantly up-regulated or dramatically suppressed. Differential expression of these genes was further identified by Northern blot. Functional analysis indicated that the regulation of their expression might contribute to the pathogenic process of HPAIV infection. In contrast, the increased expression of three IFN-stimulated genes named ISG12, LY6E, and haemopoiesis related membrane protein 1 gene might reflect host defense responses. Further study showed that ISG12 protein failed to directly interact with NS1 protein of HPAIV which expressed simultaneously in the organs where HPAIV replication occurred, by use of BacterioMatch two-hybrid system. Therefore, our findings may provide new insights into understanding the molecular mechanism underlying the pathophysiological process of HPAIV infection in chicken.     

牦牛酪蛋白基因家族的克隆及组织表达分析

本研究旨在克隆牦牛酪蛋白基因家族(CSN1S1、CSN1S2、CSN2和CSN3)的CDS区序列,鉴定其在牦牛不同组织中的表达水平。选取4岁龄左右处于泌乳期的健康类乌齐母牦牛3头,屠宰后分别采集乳腺、心脏、肝脏、骨骼肌组织,分别提取组织总RNA并反转录为cDNA,设计酪蛋白基因家族特异性引物扩增酪蛋白基因家族序列,进行生物信息学分析,并利用实时荧光定量PCR法分别检测酪蛋白家族基因mRNA水平。结果显示,克隆得到CSN1S1、CSN1S2、CSN2和CSN3基因cDNA序列分别为919、832、805和715bp,其CDS区全长分别为645、669、690和585bp,分别编码214、222、259和194个氨基酸残基。类乌齐牦牛酪蛋白基因家族与黄牛亲缘关系最近,其次是印度水牛,而与单胃动物猪的亲缘关系最远。组织表达结果显示,酪蛋白基因家族在组织中广泛表达,其中在乳腺组织中的表达量最高,其次是骨骼肌组织。在乳腺组织中CSN1S1、CSN1S2、CSN2基因之间表达量差异不显著(P>0.05),但CSN2基因表达量显著高于CSN3基因(P<0.05)。以上结果为酪蛋白基因家族在牦牛乳腺蛋白质代谢调控机制的研究提供了参考依据。     

Molecular characterization of plasmids with antimicrobial resistant genes in avian isolates of Pasteurella multocida

The complete nucleotide sequences of two plasmids from avian isolates of Pasteurella multocida that caused outbreaks of fowl cholera in Taiwan were determined. The entire sequences of the two plasmids, designated as pJR1 and pJR2, were 6792 bp and 5252 bp. Sequence analysis showed that the plasmid pJR1 contained six major genes: the first gene (sulII) encoded a type II sulfonamide resistant dihydropteroate synthase, the second gene (tetG) encoded a tetracycline resistance protein, the third gene (catB2) encoded a chloramphenicol acetyltransferase, the fourth gene (rep) encoded a replication protein, and the fifth and sixth genes (mbeCy and deltambeAy) encoded proteins involved in the mobilization of plasmid. The plasmid pJR2 contained five major genes: the first gene (deltaintI1) encoded a truncated form of a type I integrase, the second gene (aadA1) encoded an aminoglycoside adenylyltransferase that confers resistance to streptomycin and spectinomycin, the third gene (blaP1) encoded a beta-lactamase that confers resistance to ampicillin and carbenicillin, and the fourth and fifth genes might encode proteins involved in the plasmid replication or segregation. Sequence comparisons showed that the antibiotic resistance genes found in pJR1 and pJR2 exhibited a high degree of sequence homology to the corresponding genes found in a great variety of gram-negative bacteria, including Escherichia coli, Salmonella enterica Typhimurium DT104, Psedomonas spp., P. multocida, Mannheimia spp., and Actinobacills pleuropneumoniae, which suggests that these resistance genes were disseminated in these bacteria. Although sulII and tetG genes were found previously in P. multocida or Mannheimia spp., this is the first report on the presence of catB2, aadA1, and blaP1 genes in bacteria of the family Pasturellaceae. Moreover, the aadA1 and blaP1 genes found in pJR2 were organized into an integron structure, which is a site-specific recombination system capable of capturing and mobilizing antibiotic resistance genes. This is also the first report on the presence of an integron in bacteria of the family Pasteurellaceae. The presence of a P. multocida integron might facilitate the spreading of antibiotic resistance genes between P. multocida and other gram-negative bacteria.     

大肠杆菌刺激和LPS诱导条件下猪小肠上皮细胞FUT1和FUT2基因表达变化

本实验运用Real-time PCR方法检测分析α-(1,2)岩藻糖转移酶1(FUT1)和α-(1,2)岩藻糖转移酶2(FUT2)基因在大肠杆菌(E.coli)F18ab、F18ac感染以及内毒素(LPS)诱导小肠上皮细胞(IPEC-J2)前后的mRNA表达差异,在细胞水平上进一步验证FUT1、FUT2基因的功能并探讨其在抗E.coli F18侵染过程中的作用机制。结果表明:FUT1、FUT2基因在E.coli感染和LPS诱导细胞后的mRNA表达水平均极显著升高(P0.01),且FUT2基因的上升趋势要高于FUT1基因。由此推测,FUT1和FUT2基因的表达水平与仔猪抵抗E.coli F18感染的能力密切相关,FUT2基因可能发挥着比FUT1基因更重要的调控作用。