保幼激素类似物对白蚁的作用研究进展

本文介绍了保幼激素类似物对白蚁的影响,包括诱导前兵蚁、兵蚁和一些中间品级(形态畸形)的产生、抑制白蚁的取食、减少或消除白蚁的共生原生动物群、对白蚁产生不同水平的急性和慢性毒性、抑制工蚁蜕皮以及繁殖蚁建立新群体等方面的影响,其中最主要影响是诱导前兵、兵蚁和一些中间品级的产生破坏了白蚁群体品级比例的平衡性或完整性。因此,保幼激素类似物可用于白蚁的防治,并在田间防治散白蚁和乳白蚁均取得了较好的防治效果,并探讨了应用保幼激素类似物防治白蚁的潜力与前景。     

向日葵3个谷胱甘肽-S-转移酶GST基因的克隆及表达模式分析

从向日葵转录组测序结果中获得了3个对盐胁迫有响应的谷胱甘肽-S-转移酶（GST，EC2.5.1.18）GST基因，构建了系统进化树并进行分析，得知这3个基因属于Tau型GST，并将它们命名为HaGSTU26（HanXRQChr04g0127901）、HaGSTU8（HanXRQChr06g0177581）、HaGSTU27（HanXRQChr10g0316331），然后以向日葵Sk02R为试验材料，克隆这3个基因，并进行了不同组织和不同胁迫条件下的表达分析。序列分析表明：HaGSTU26基因组为1674bp，CDS（编码蛋白序列）长666bp，编码221个氨基酸，由2个外显子和1个内含子组成；HaGSTU8基因组为2271bp，CDS长654bp，编码217个氨基酸，由2个外显子和1个内含子组成； HaGSTU27基因组为663bp，CDS长663bp，编码220个氨基酸,由1个外显子组成。实时荧光定量PCR分析表明：向日葵HaGSTU26、HaGSTU8、HaGSTU27基因在不同组织（根、幼叶、成熟叶、茎、幼茎、苞叶）中表达量不同，其中，HaGSTU26基因和HaGSTU27基因在根中表达量最高，而HaGSTU8基因在苞叶中表达量最高，但这3个基因均在成熟茎中的表达量最低。在不同胁迫条件下，测定这3个基因在向日葵幼苗中的表达量，结果表明在盐及ABA胁迫下，基因表达量均随着处理时间的增加而呈现先增加后下降的趋势。其中，在盐胁迫下，HaGSTU26基因在12 h后相对表达量最高，HaGSTU8及HaGSTU27基因表达量在3h后相对表达量最高。在ABA胁迫后，HaGSTU26及HaGSTU27基因表达量在12 h后相对表达量最高，HaGSTU8在24 h后相对表达量最高。在冷胁迫下，HaGSTU26和HaGSTU27基因上调表达,它们分别在3、24 h后相对表达量最高，HaGSTU8基因下调表达，其相对表达量随处理时间的延长呈现逐渐减少的趋势。在热胁迫条件下，这3个基因的相对表达量随着胁迫时间的延长而增加,均在24 h后表达量最高。以上结果说明这3个基因对不同非生物胁迫（盐、ABA、冷、热胁迫）均有响应。     

台湾乳白蚁4个地理种群遗传分化的研究

采用线粒体COⅡ基因为分子标记对中国南部4个台湾乳白蚁地理种群的遗传分化进行了初步研究。结果显示,4个地理种群共有9个多态位点和8种单倍型;种群间遗传分化统计量F_st与地理距离无显著相关。探讨了台湾乳白蚁种群分化的影响因素和相应的防治对策。     

黏虫保幼激素结合蛋白基因MsJHBP3生物学功能及对黏虫生长发育的影响

保幼激素结合蛋白（juvenile hormone binding protein,JHBP）是一类载体蛋白,与保幼激素（juvenile hormone,JH）结合形成复合体后将保幼激素运送到靶器官处调控昆虫的生长发育。本试验在黏虫Mythimna separata转录组中获得7条保幼激素结合蛋白基因,筛选获得一条经保幼激素诱导后高表达的保幼激素结合蛋白MsJHBP3(GenBank登录号：MZ577068),c DNA全长为839bp,开放读码框长度729bp,编码242个氨基酸,氨基酸等电点为5.35,分子量为27.02kDa。不同发育阶段研究表明,Ms JHBP3在蛹期表达量最高,2龄表达量最低。RNA干扰处理4龄幼虫后6 h基因抑制效率最好,达79.72%。干扰后虫体内保幼激素含量为对照的1.14倍;羽化率和化蛹率均较对照组显著降低,羽化率下降7.42%,化蛹率下降3.75%;Ms JHBP3干扰后转录组测序数据分析共获得212个差异基因,其中105个上调基因,107个下调基因,其中保幼激素甲基转移酶基因、保幼激素环氧水解酶基因、保幼激素酯酶基因均上调。本研究表明MsJHBP...     

水稻热休克蛋白HSP70基因克隆、表达分析及原核表达

为明确水稻热休克蛋白70（heat shock protein 70,HSP70）基因在逆境胁迫下的表达特征,以日本晴粳稻水稻品种为材料,通过基因克隆方法获得水稻HSP70基因cDNA全长序列,并采用生物信息学的方法分析其序列特征,利用实时荧光定量PCR（quantitative real-time PCR,RT-qPCR）技术测定不同水稻组织、不同激素、不同温度以及不同逆境下HSP70基因的相对表达量,同时对其原核表达条件进行优化。结果表明,水稻HSP70基因全长1 950 bp,预测蛋白大小为71.18 kD,等电点为5.10,亚细胞定位于细胞质内,有较强的亲水性。水稻HSP70蛋白序列与香蕉HSP70蛋白序列的亲缘性较高;水稻HSP70基因表达具有组织特异性,在茎中的相对表达量最高,在根中最低;低温胁迫后,水稻HSP70基因在12 h内基因相对表达量相对稳定,在24 h时相对表达量达到峰值,为9.60;高温胁迫后,在较短时间内水稻HSP70基因显著上调并达到峰值,为79.10;激素吲哚乙酸、脱落酸和油菜素内酯均能诱导水稻HSP70基因表达;但在甘露醇模拟干旱和NaCl盐胁迫处理下,水稻HSP70基因的相对表达量呈现先升后降的趋势。水稻HSP70蛋白的最佳诱导温度是30℃,异丙基-β-D-硫代吡喃半乳糖苷最佳诱导浓度为1.2 mmol/L。     

温度胁迫下沙葱萤叶甲小热激蛋白基因GdHsp20.6的克隆及表达分析

为明确小热激蛋白在沙葱萤叶甲Galeruca daurica应对温度胁迫中的作用，采用PCR方法克隆沙葱萤叶甲小热激蛋白基因Hsp20（GdHsp20.6）完整的开放阅读框（open reading frame，ORF）序列，应用在线软件对GdHsp20.6基因进行生物信息学分析，通过原核表达技术诱导表达及纯化其编码蛋白，并通过实时荧光定量PCR（real-time quantitative PCR，RT-qPCR）技术分析不同温度胁迫下GdHsp20.6基因的表达量。结果显示，GdHsp20.6基因ORF序列长度为543 bp，编码180个氨基酸，预测分子量为20.6 kD，无跨膜区和信号肽。GdHsp20.6氨基酸序列有高度保守的α-结构域。GdHsp20.6氨基酸序列与其它鞘翅目昆虫的Hsp20氨基酸序列有较高的一致性，其中与花绒寄甲Dastarcus helophoroides的Hsp20.99氨基酸序列的一致性最高，为63%。GdHsp20.6基因在大肠杆菌Escherichia coli BL21（DE3）细胞系中成功表达，经异丙基-β-D-硫代吡喃半乳糖苷（isopropyl-β-d-thiogalactoside，IPTG）诱导后GdHsp20.6蛋白成功表达，十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（sodium dodecyl sulfate-polyacrylamide gel electrophoresis，SDS-PAGE）和Western-blot分析表明融合蛋白大小与预测大小一致，并纯化获得了纯度较高的目的蛋白GdHsp20.6。低温（-10~5℃）和高温（35~40℃）处理1 h以及处理后25℃恢复30 min均能诱导GdHsp20.6基因表达上调，并且0℃处理30~120 min也能诱导GdHsp20.6基因表达上调。表明GdHsp20.6基因在沙葱萤叶甲应对低温和高温胁迫中可能起着重要作用。     

马铃薯通用应激蛋白StUSP基因家族的鉴定及逆境表达模式分析

在全基因组和转录组水平系统鉴定马铃薯USP通用应激蛋白基因家族,并对该家族成员的基本特征及其在不同逆境胁迫下的表达模式进行分析。同时以马铃薯干旱耐受型品种‘陇薯10号’（L）和干旱敏感型品种‘大西洋’（D）为试验材料,利用高通量测序全面分析StUSP家族成员在干旱胁迫下的表达特性,筛选干旱胁迫关键差异表达基因。结果表明：马铃薯基因组中共有42个基因编码含有USP结构域的蛋白质,在11条染色体上不对称分布,且主要分布在1~6号染色体上。绝大多数StUSPs含有多个内含子。胁迫表达分析显示StUSPs能够响应多种非生物胁迫,且在干旱耐受性不同的马铃薯品种中差异表达。同时,利用qRT-PCR分析了12个成员干旱胁迫下表达模式,除StUSP12、StUSP22下调表达外,其余10个基因均正响应干旱胁迫。     

广聚萤叶甲雄虫生殖系统特异性精液蛋白基因的筛选及表达分析

为明确广聚萤叶甲Ophraella communa雄虫精液蛋白基因在性别间的表达差异并筛选出在雄虫生殖系统特异性表达的基因，从转录组及蛋白组数据库选取13个精液蛋白基因，采用实时荧光定量PCR技术检测其在广聚萤叶甲不同性别、组织及发育阶段的表达特征。结果显示，在广聚萤叶甲雄虫13个精液蛋白基因中，有9个精液蛋白的mRNA表达水平在雄虫中更高，有5个精液蛋白基因具有专一的雄虫生殖系统特异性，分别为PGK、sucA、ENO、SDH和PLA2b基因，在雄虫生殖系统中的表达量分别较其在头部的表达量高273.01倍、401.48倍、11.21倍、64.27倍和1.86倍。PGK、sucA和ENO基因均在广聚萤叶甲老熟蛹期急剧上调表达，在性成熟成虫中的表达量最高，分别是卵期表达量的43.48倍、31.03倍和11.89倍，三者具有明显的组织和发育阶段时空特异性，推测PGK、sucA和ENO基因参与广聚萤叶甲雄虫生殖的可能性较其余基因更高。     

高粱BR信号转录因子BZR1基因家族的鉴定及激素应答分析

为研究高粱转录因子BZR1基因家族的表达特征,以高粱BTx623为材料,通过生物信息学及实时荧光定量PCR (quantitative real-time PCR,qPCR)技术对高粱BZR1基因家族进行鉴定和激素应答分析。结果表明,在高粱基因组中共鉴定到9个BZR1基因家族成员,根据染色体位置命名为SbBZR1-1~SbBZR1-9,其氨基酸序列长度在191~716 aa之间,理论分子量大小在20.99~80.41 kD之间,理论等电点在4.75~10.62之间;系统进化树分析显示,高粱BZR1基因家族与单子叶水稻和玉米的同源性为67%~100%;该家族各个成员之间外显子和内含子的数量差异较大。SbBZR1-3、Sb-BZR1-4和SbBZR1-9基因在高粱不同器官中的表达具有组织特异性;经200 μmol/L脱落酸处理后,SbBZR1-3基因的相对表达量逐渐升高,在9 h时达到最大,而高粱SbBZR1-4和SbBZR1-9基因的表达受到显著抑制;SbBZR1-3和SbBZR1-4基因在1 μmol/L油菜素内酯诱导下呈降低-升高-降低的表达趋势,但SbBZR1-9基因的表达受到显著抑制;在1 mmol/L γ-氨基丁酸和100 μmol/L褪黑素处理下,SbBZR1-3、SbBZR1-4及SbBZR1-9基因均显著上调表达;经10 μmol/L吲哚乙酸处理后,Sb-BZR1-3基因呈先升高后降低的表达趋势,SbBZR1-9基因的表达受到显著抑制,SbBZR1-4基因呈升高-降低-升高-降低的表达趋势。表明高粱BZR1基因家族在激素应答过程中具有重要作用。     

The ovicidal properties of the juvenile hormone mimic sumitomo S-31183 (SK-591) to insects

S-31183 was assayed against preimaginal stages of the tobacco whitefly,Bemisia tabaci (Genn.), and eggs of the Egyptian cotton leafworm,Spodoptera littoralis (Boisd.). The compound was found to be an ovicide forB. tabaci eggs in both preinfestation and postinfestation treatments. FreshS. littoralis eggs were very susceptible to the compound at 0.05 ppm a.i., response was much poorer with 1-2-day-old eggs and 2-3-day-old eggs were not affected even by 100 ppm. Publication of the Agricultural Research Organization. No. 2271-E, 1988 series.     

喜树碱对小菜蛾体内保幼激素及蜕皮激素滴度的影响

为明确喜树碱对小菜蛾Plutella xylostella生长发育的抑制作用及其机制,设置0.5、1.0、2.0mg/m L剂量处理其3龄幼虫,采用浸叶饲喂法和高效液相色谱法测定了喜树碱对小菜蛾体内蜕皮激素和保幼激素滴度的影响。结果显示,喜树碱各剂量处理均显著抑制了小菜蛾幼虫的生长发育,抑制率最高达到28.42%;各处理小菜蛾化蛹时间均延迟,异常蛹增多,羽化率降低;其中2.0 mg/m L处理后4 d其化蛹率为6.67%,对照组化蛹率为86.60%。0.5、1.0 mg/m L处理下,小菜蛾体内蜕皮激素滴度显著低于对照组,仅为对照组的0.06倍;而保幼激素滴度增加,分别可达到28.74mg/m L和36.29 mg/m L,是对照组的9倍左右。表明喜树碱可影响小菜蛾体内蜕皮激素和保幼激素的平衡,延迟和影响了小菜蛾的正常发育进程,可实现对小菜蛾种群的控制作用。     

Effect ofMelia azedarach fruit extract on juvenile hormone titer and protein content in the hemolymph of two species of noctuid lepidopteran larvae [insecta: Lepidoptera: Noctuidae]

The effect of an enriched methanolic extract ofMelia azedarach L. (Meliaceae) fruits on the size of the corpora allata (CA), the juvenile hormone (JH) titer and the protein content in the hemolymph of two lepidopteran pests in Egypt,Spodoptera littoralis (Boisd.) andAgrotis ipsilon (Hufn.), was studied. Different concentrations of the extract were incorporated into an artificial diet on which the larvae were allowed to feed. InS. littoralis, a significant reduction in the CA volume of larvae treated at the 1000 ppm extract levelvs that of control larvae was observed. In A.ipsilon, a reduction was found in the right CA gland only. Larvae of both species that had fed on a diet withMelia extract had a higher mean JH-II titer in the hemolymph than did control larvae. In both species, the content of hemolymph protein was decreased significantly after feeding for 6 days on a diet treated with concentrations above 50 ppm extract, followed by 6 days on a normal diet. The results show that aM. azedarach fruit extract has an effect on the neuroendocrine control in the insects. The effect on the hemolymph protein levels is discussed in connection with changes in the morphology/physiology of the gut.     

A juvenile hormone analog, pyriproxifen, affects some biochemical components in the hemolymph and fat bodies of Eurygaster integriceps Puton (Hemiptera: Scutelleridae)

Endocrine system has a critical role during the developmental stages of insects by synthesis of several regulatory hormones. One of these hormones is juvenile hormone that several insecticides have been driven based on its biochemical structure e.g. pyriproxifen. Due to various disadvantages of fenitrothione spraying, this study was carried out finding the possible usage of pyriproxifen to control the destructive population of Eurygaster integriceps. After bioassay treatments to acquire the appropriate concentrations, the treatment repeated to find possible changes in the biochemical compounds of hemolymph and reserved macromolecules in fat bodies. Results showed significant discrepancies in amount of biochemical components of the hemolymph and the reserved macromolecules in E. integriceps after pyriproxifen treatment. In hemolymph, activity level of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase as enzymatic components and uric acid as non-enzymatic one increased but acid phosphatase, lactate dehydrogenase, protein, trehalose and lipid showed adverse results. In fat bodies, the amount of all measured reserves including glycogen, lipid and protein decreased and showed significant differences. These kinds of changes have been supported by several studies due to using insecticides. These negative effects on overall physiology of the Sunn pest by depleting the essential compounds cause sensitivity to fungal infections and several shortages for normal development and reproduction of insect. Also, the adaptability of pyriproxifen to increase the effect of entomopathogenic fungus, Beauveria bassiana, should be considered to initiate a new pest management program to decrease the production loss made by E. integriceps in wheat fields.     

幼龄期压砂地枸杞产量和品质多指标耦合灌溉制度优化

为提高宁夏中部干旱带幼龄期压砂地枸杞灌水效率,保障枸杞产量和品质,进行了3水平灌水定额(300、225 m~3·hm~(-2)和150 m~3·hm~(-2))的田间对比试验,采用综合指标增量最优方法对灌溉制度进行了优化。研究发现:枸杞5月上旬萌芽期耗水以土壤蒸发为主,日耗水量0.6～1.2 mm,6月中旬进入夏果花期耗水量增大,日耗水量2.5～3.7 mm,7月中旬枸杞夏果期耗水量继续增大,达2.4～4.3 mm,7月下旬日耗水量最大,为3.2～4.7 mm,8月中旬耗水量下降,日耗水量3.0～4.2 mm。灌水定额对枸杞产量影响显著(P0.05),灌水定额300 m~3·hm~(-2)时产量最高,为1 402.65 kg·hm~(-2);灌水定额225 m~3·hm~(-2)时枸杞多糖、β-胡萝卜素和黄酮较高,含量分别为4.56%、0.15%和0.41%;灌水定额150 m~3·hm~(-2)时枸杞甜菜碱含量较高,为0.77%。进一步通过综合指标增量最优方法进行优化,结果表明β-胡萝卜素含量最高时得到综合指标增量最大,为-5.4%,总耗水量为450 mm。枸杞夏果花期进入需水关键期,阶段耗水量达70 mm以上,进入6月中旬枸杞需水量增大,旬耗水量达29 mm以上。可见,幼龄期压砂地枸杞产量及品质指标均达到最优的耗水量较难获得,但是在β-胡萝卜素含量最高时可以获得产量和品质多指标耦合的最优耗水量,据此进行灌溉制度优化,可以一定程度上实现幼龄期压砂地枸杞优质高产。     

Stage-specific action of juvenile hormone analogs

The discovery of juvenile hormones (JH) and their synthetic analogs (JHA) generated excitement and hope that these compounds will replace first- and second-generation insecticides that have not so desirable environmental and human safety profiles. However, JHAs used commercially during the past four decades did not meet these expectations. The recent availability of advanced molecular and histological methods and the discovery of key players involved in JH action provided some insights into the functioning of JHA in a stage and species-specific manner. In this review, we will summarize recent findings and stage-specific action of JHA, focusing on three commercially used JHA, methoprene, hydroprene and pyriproxyfen and economically important pests, the red flour beetle, Tribolium castaneum, and the tobacco budworm, Heliothis virescens, and disease vector, the yellow fever mosquito, Aedes aegypti.     

Pyridyl terpenoid ethers with high juvenile hormone activity

Pyridyl terpenoid ethers have outstanding juvenile hormone activity in Tenebrio molitor compared with their phenyl analogues (6,7-epoxy-3,7-dimethyloct-2-enyl 6-ethyl-3-pyridyl ether and 7-ethoxy-3,7-dimethyloct-2-enyl 6-ethyl-3-pyridyl ether are active at 100 pg/larva). The compounds were also active in Galteria mellonella and Culex pipiens.     

禾谷缢管蚜体内保幼激素的变化趋势

为明确禾谷缢管蚜Rjopalosiphum padi 不同发育阶段体内保幼激素(ju-venile hormone,JH)的变化趋势,借助高效液相色谱(HPLC),确定了蚜虫JH测试方法,并对其JH进行了测定.结果表明:在若蚜阶段存在三种JH即JHⅠ、JHⅡ和JHⅢ;在成蚜阶段只能检测到JHⅢ.在整个发育过程中,JH变化趋势为虫龄越高,JH滴度越低,无翅3、4龄若蚜体内三种JH均极显著高于同期有翅若蚜.母代翅型对子代不同龄期若蚜JH滴度有明显影响.无翅成蚜后代1龄JH滴度极显著高于同期有翅成蚜的后代;2龄时,有翅成蚜的后代JH滴度骤然上升;有翅成蚜后代在2、3龄时JH滴度极显著高于同期无翅成蚜的后代.2龄之前是两种翅型母代的后代滴度变化的转折点,表明1～2龄若蚜期是禾谷缢管蚜翅型分化的关键时期和JH影响翅型分化的敏感龄期.     

Substituted thiotrifluoropropanones as potent selective inhibitors of juvenile hormone esterase

A series of 27 substituted thio-1,1,1-trifluoropropanones was synthesized by reacting the corresponding thiol with 1,1,1-trifluoro-3-bromopropanone. The resulting sulfides were screened as inhibitors of hemolymph juvenile hormone esterase and α-naphthyl acetate esterase activity of the cabbage looper, Trichoplusia ni, electric eel acetylcholinesterase, bovine trypsin, and bovine α-chymotrypsin. The presence of the sulfide bond increased the inhibitory potency on all of the enzymes tested when compared with compounds lacking the sulfide. In general, the compounds proved to be poor inhibitors of chymotrypsin and moderate inhibitors of trypsin. By varying the substituent on the sulfide, good inhibitory activity was obtained on α-naphthyl acetate esterase, acetylcholinesterase, while some of the compounds proved to be extremely powerful inhibitors of juvenile hormone esterase. The most powerful inhibitor tested was 3-octylthio-1,1,1-trifluoro-2-propanone, with an I₅₀ of 2.3 × 10^?9M on JH esterase. This compound showed a molar refractivity similar to that of the JH II backbone, was not toxic to T. ni, and was moderately toxic to mice, with a 48-hr LD₅₀ of >750 mg/kg. It effectively delayed pupation when applied to prewandering larvae of T. ni, as expected for a JH esterase inhibitor. Thus, some members of this series are promising for evaluating the role of JH esterase in insect development. The series also indicates that, by varying the substituent on the sulfide moiety, potent “transition-state” inhibitors can be developed for a wide variety of esterases and proteases.