The toxicity test of imidaclothiz pesticide on silkworm was carried out in order to evaluate its effect used in the prevention and control of pests on silkworm. The study indicated 8 000 mg/L of imidaclothiz had no fumigation toxicity to the 3rd instar larvae under the experimental condition. In the tag toxicity test, 100 mg/L of imidaclothiz could cause the 3rd, 4th and 5th instar larvae 100% poisoned. Feeding the 3rd, 4th and 5th newly molted instar larvae respectively with imidaclothiz aqueous solution for 6 h continuously, the LC50 was 3rd ＞ 4th ＞ 5th instar larvae. The result showed imidaclothiz exerted a significant effect on silkworm cocooning. The residual period of imidaclothiz on mulberry was affected by various factors, and poisoning symptoms of silkworm were still visible around 20 days. Because of its strong stomach toxicity to silkworm and long residual period in mulberry leaves, imidaclothiz cannot be used for field and forest pest control around the silkworm area.

鲁诱7号是四倍体植株,产叶量大且叶质优良.养蚕成绩各项均比湖桑32号提高6％以上,全年产叶量比湖桑32号提高17.48％.鲁诱7号桑椹产量为1000～1200 kg/667 m2,桑椹中含有丰富的营养物质及微量元素,即可鲜食又可加工利用.鲁诱7号植株无冻枯死亡现象,桑椹菌核病发病率仅为6.23％,适合北方地区栽植推广.

乙烯响应因子(ethylene responsive factors,ERFs)是植物特异性转录因子,参与多种生物过程,特别是非生物胁迫耐受.研究干旱胁迫下MnERF2的表达情况,为研究桑树AP2/ERF转录因子的抗逆分子机制提供基础理论数据.从桑树中鉴定了一个ERF转录因子亚家族成员,命名为MnERF2,对其进行生物信息学分析,并通过瞬时转化分别获得过表达MnERF2和RNA干扰(RNAi)沉默MnERF2桑树植株,利用功能增益和功能损失方法分析其抗旱功能.结果显示,MnERF2开放阅读框为1050 bp,编码349个氨基酸,编码蛋白质分子量为39.48 kD,理论等电点为5.6,具有一个典型的AP2/ERF保守结构域.过表达MnERF2显著提高桑树对干旱胁迫的耐受性,相比之下,MnERF2的沉默显著降低了对干旱胁迫的耐受性.进一步试验表明,MnERF2增强SOD、POD、CAT、GST活性,促进ASA、GSH、脯氨酸含量的升高,降低O2·-、H2O2、·OH、MDA的含量和电解质渗透率.MnERF2通过提高脯氨酸的生物合成来调节渗透势,通过提高抗氧化酶活性和抗氧化物质含量来提高活性氧的清除能力,从而提高桑树干旱胁迫的耐受性.

AP2/ERF类转录因子是植物所特有的一类转录因子家族,在植物的生长发育及响应非生物胁迫中发挥着重要作用.为发掘桑树AP2/ERF类转录因子的成员及其功能,从桂桑优12中克隆到7个AP2/ERF转录因子,命名为MnAP2/ERF1～MnAP2/ERF7.生物信息学分析结果表明,这7个AP2/ERF蛋白都属于不稳定蛋白,且均属于亲水性蛋白,二级结构以无规则卷曲为主,亚细胞定位显示主要位于细胞核中.氨基酸序列比对及进化树分析发现,这7个AP2/ERF转录因子均含有1个保守AP2结构域,其中MnAP2/ERF1～MnAP2/ERF4属于ERF亚家族,MnAP2/ERF5～MnAP2/ERF7属于DREB亚家族.荧光定量分析显示,NaCl、PEG6000、水淹胁迫可诱导7个桑树AP2/ERF基因上调表达,其中MnAP2/ERF3、MnAP2/ERF5、MnAP2/ERF6分别响应水淹、干旱和盐胁迫,说明桑树AP2/ERF转录因子的表达与逆境胁迫响应之间有密切的联系.本研究结果可为进一步揭示AP2/ERF转录因子调控桑树生长发育及逆境胁迫的机理奠定基础.

聚六亚甲基双胍盐酸盐是一种环保型高效杀菌消毒剂,将聚六亚甲基双胍盐酸盐配制成含5.0 g·L-1碳酸钠的复配药液,100 mg·L-1的复配药液对家蚕核型多角体病毒和质型多角体病毒的消毒效果为100％,200 mg·L-1的复配药液对家蚕白僵菌、 黄曲霉菌的消毒效果为100％,2000 mg·L-1的复配药液对苏芸金芽孢杆菌无消毒效果,200 mg·L-1的复配溶液对沙雷铁氏菌消毒30 min,皮下穿刺的发病率为0.复配药液敞口存放2 d对家蚕多角体病毒仍然有较好的消毒效果,4～5龄隔天添食24 h复配药液对家蚕全茧量、 茧层量、 茧层率未见不良影响.聚六亚甲基双胍盐酸盐复配消毒液不仅可用于蚕室蚕具消毒,也可用于桑叶叶面消毒.

为探明桑树AP2/ERF转录因子MnERF2基因对桑树耐盐胁迫能力的影响,利用构建好的植物过表达和抑制表达载体瞬时转化桑树,并比较分析NaCl胁迫前后瞬时转化桑树中的活性氧(ROS)含量、抗氧化酶活性、抗氧化物质含量以及抗氧化酶基因的表达量,以综合评定MnERF2基因的耐盐功能.通过荧光定量RT-PCR对盐胁迫后MnERF2表达量的分析显示,成功获得MnERF2基因瞬时过表达(OE)、抑制表达(RNAi)转基因植株.进一步的生理指标分析结果显示,不同时间盐胁迫下瞬时过表达MnERF2植株中的ROS(O2·-、H2 O2、·OH)和丙二醛(MDA)含量明显低于对照和RNAi株系,过氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、谷胱甘肽S-转移酶(GST)活性以及抗坏血酸(AsA)、还原型谷胱甘肽(GSH)、脯氨酸含量高于对照和RNAi株系,且48 h处理下SOD、POD、CAT三种酶基因表达量显著高于对照和RNAi株系.说明MnERF2基因响应桑树的盐胁迫,通过提高植株的保护酶活性和抗氧化物质含量、降低活性氧氧化及细胞损伤程度提高桑树的耐盐能力.

为探究施加外源24-表油菜素内酯(EBR)对桑树耐盐性的影响,以桑品种桂桑优12为材料进行盆栽试验,在200 mmol·L-1 NaCl胁迫下,研究外施不同浓度(0.01、0.10、1.00 μmol·L-1)EBR对盐胁迫下桑树幼苗质量、根系特征、光合色素含量、活性氧(ROS)水平、丙二醛(MDA)含量、相对电导率、抗氧化酶活性和渗透调节物质含量等生理指标的影响.结果 表明,与单一NaCl胁迫相比,外源添加0.10μmol·L-1EBR后,桑树幼苗地上鲜质量和干质量、主根长、总根长、根表面积、根平均直径、根总体积、叶绿素和类胡萝卜素含量均提高,叶片与根中产生羟基自由基(·OH)能力、产生超氧阴离子自由基(O2)活力、过氧化氢(H2O2)含量降低;叶片与根中的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性升高;脯氨酸、可溶性蛋白和可溶性糖含量增加;相对电导率和MDA含量降低.其中地下部鲜质量和根体积是盐胁迫下的1.56和1.57倍,叶片中CAT活性和可溶性糖含量达到盐胁迫下的1.57和1.68倍.本研究为揭示外施油菜素内酯增强桑树耐盐性的生理调控机制提供了参考依据.

甲磺酸培氟沙星是喹诺酮类的第3代抗菌药物,对苏云金芽孢杆菌和黑胸败血芽孢秆菌感染引起的家蚕细菌性败血病,接菌后添食24 h有效防治质量浓度最低为5.0 mg/L;先用苏云金芽孢杆菌对5龄起蚕进行皮下穿刺接菌,8h内添食药物对细菌病有较好的防治效果;采用苏云金芽孢杆菌对5龄起蚕进行皮下穿刺,接菌后添食2、4、8、12 h的药叶,最低防治质量浓度分别为20.0、10.0、10.0、5.0 mg/L;5龄起蚕添食2、4 h的药叶后接菌,有效防治质量浓度为20.0 mg/L,8 h后喂食试验浓度内药物防治效果已不佳.采用质量浓度为200.0、100.0 mg/L的甲磺酸培氟沙星和盐酸环丙沙星溶液蘸桑叶饲蚕,其全茧量及茧层率与对照组比较未见显著差异.

探讨换气孔数量及饲养台姿态对家蚕生长和茧质性状的影响.饲养蚕筐设置40个和80个孔径为10 m m的换气孔区,再将换气孔区分为饲养台水平区和倾斜区,倾斜区两长边高度分别为4 cm、6 cm.结果显示,4个试验区2龄眠蚕体重处于同一统计水平,均大于对照区,且与对照区有显著差异;茧质调查结果表明,40孔水平区的全茧量与对照存在显著差异,其他试验区的全茧量、茧层量和茧层率无显著差异.

在实验条件下,饲养框内的O2含量随家蚕的生长和时间的延长而减少,2龄眠蚕体重与O2含量有强相关性,全茧量、茧层量等指标无显著差异;添食1.0×105 PIB·m L-1、1.0×106 PIB·mL-1、1.0×107 PIB·mL-1的BmCPV,随着O2含量的降低,家蚕对BmCPV的抵抗力也随之降低,说明保持饲养环境的O2含量对增强家蚕体质具有重要意义.

斜纹夜蛾核型多角体病毒Ⅱ型(SpltNPVⅡ)基因组DNA含有7个同源重复区(hr).采用脂质体介导转染法和实时荧光定量PCR对7个hr在异源病毒感染的BmN和Sf21细胞中的复制原点功能进行分析.结果 表明,SpltNPVⅡhr在BmN和Sf21细胞中均具有复制原点功能,但其复制起始能力不同.BmNPV感染的BmN细胞中,hr4复制起始能力最强,每微克DNA中的拷贝数达4.05× 105个,hr5复制起始能力最弱,仅为2.21×104个拷贝/μg;AcMNPV感染的Sf21细胞中hr1复制起始能力最强,可达5.92× 106个拷贝/μg,hr5复制起始能力最弱,仅为1.91×104个拷贝/μg.另外,SpltNPVⅡhr在异源细胞中的复制起始能力与其所含回文序列及复制相关的基序等特征结构的数目存在显著的正相关.

斜纹夜蛾核型多角体病毒Ⅱ型(SpltNPVⅡ)基因组DNA含有7个同源重复区(hr).采用脂质体介导转染法和瞬时表达实验对7个hr在异源病毒感染的BmN和Sf21细胞中增强异源ie1启动子转录活性的功能进行分析.结果 表明,除hr5外,SpltNPVⅡhr均能增强BmNPVie1启动子的转录活性,其中hr1、hr4和hr7增强效率较高,为对照的30～ 40倍;7个hr均能显著增强AcMNPV ie1启动子的转录活性,其中hr7增强效率高达1 246倍,其余增强效率在17～538倍之间.另外,SpltNPVⅡhr增强异源ie1启动子转录活性的效率与其所含的正反向重复序列、回文序列以及与复制相关的基序等特征结构的数目存在显著的正相关.

斜纹夜蛾核型多角体病毒Ⅱ型(Spodoptera litura nucleopolyhedrovirusⅡ,SpltNPVⅡ)基因组DNA同源重复区hr1大小为1746 bp,含有6个64 bp不完全回文序列、4个正向重复序列以及7个与病毒基因组DNA复制相关的基序.瞬时表达分析结果表明,SpltNPVⅡhr1在感染野生型家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus,BmNPV)和苜蓿丫纹夜蛾多粒包埋型核多角体病毒(Autographa californica multiple nucleopolyhedrovirus,AcMNPV)的BmN和Sf21细胞中均具有增强早期基因ie1启动子活性的功能,增强效率分别为30、350倍;实时荧光定量PCR结果显示,hr1在BmN和Sf21细胞中具有基因组DNA复制起始原点的功能,拷贝数分别为(8.46×104±6.13×103)、(5.92×106±2.95×105)copies/μg DNA.研究证明,SpltNPVⅡhr1在异源细胞BmN和Sf21中具有复制起始原点和增强子的双功能作用.

为探讨大田农药吡丙醚对蚕茧生产的影响,进行了低浓度吡丙醚添食试验.结果表明,吡丙醚对家蚕结茧影响较大,5龄第4天添食1.00×10-3 mg/L、5.00×10-4 mg/L、2.50×10-4 mg/L的吡丙醚24 h,对家蚕的结茧有影响,但到5龄第14天能够全部结茧;用1.00×10-2 m g/L、1.00×10-3 mg/L的吡丙醚,在5龄不同时间分别添食24 h,添食越晚,结茧率越低;从5龄第4天连续添食6.25×10-5 mg/L、3.13×10-5 mg/L的吡丙醚、从5龄第5天连续添食6.25×10-5 mg/L的吡丙醚,均可造成家蚕不结茧.吡丙醚在桑叶上的残效期超过47 d.

为探讨小蚕饲育方式对蚕儿生长的影响,进行了浅塑料筐养蚕比较试验.将塑料筐养蚕分设成有饲养台区和无饲养台区,有饲养台区细分为石灰区、置换区和高架区,无饲养台区细分为覆膜区和空白区.结果表明:5种饲育方式的全茧量、茧层量、茧层率无显著差异;2龄眠蚕体重石灰区、置换区与覆膜区,以及与高架区、空白区有显著差异;石灰区、置换区对BmNPV的抗性优于空白区.

The experiment on Boscalid and Bromothalonil synergistic control of silkworm mycosis was conducted.The results indicated that,due to the addition of Bromothalonil,the disinfection effect increased from 42.7% to 100.0% against Aspergillus flavus with 0.5 mg/mL Boscalid,Bromothalonil at concentrations of 0.625mg/mL and 0.312 5mg/mL had no significant difference in disinfection effect of Boscalid against Aspergillus flavus;due to the addition of Boscalid at a concentration of 1mg/mL and 2mg/mL,disinfection effect increased from 2.67% to 49.3% and 24.7% against Beauveria bassiana with 0 .312 5mg/mL Bromothalonil.

The test of increasing oxygen content in rearing seat was carried out to deal with the development of young silkworm inhibited by too low oxygen content.The newly-hatched larva,amount to 1.0 g silkworm egg,were reared in the plastic box with cover,bottom of 26 cm × 13 cm,upper base of 27 cm × 14 cm and height of 4 cm.The redundant young silkworm was weeded out in experiment.The oxygen content in the rearing room for 1 st and 2nd instar silkworm was increased using different ratios of sodium percarbonate and calcium hydroxide as oxygenate,which could promote the growth of the young silkworm.The silkworm body weight increased significantly in the three treatments,5.0 g of sodium carbonate adding 5.0 g of calcium hydroxide,2.5 g of sodium carbonate adding 7.5 g of calcium hydroxide and 10.0 g of calcium hydroxide.The results indicated that the effect of calcium hydroxide was better than that of sodium percarbonate.There was no significant difference between the dosage of 10.0 and 30.0 g of calcium hydroxide with replacing the reagent one time every day or every instar (P ＞ 0.05).

利用生物信息学方法,对斜纹夜蛾核型多角体病毒Ⅱ型分离株基因组DNA序列进行分析.结果表明,斜纹夜蛾核型多角体病毒Ⅱ基因组DNA含有7个同源重复区,分别包含3~8个64 bp不完全回文序列,在回文序列中心均含有一个PvuI限制性酶切位点,并且存在多个正向或反向互补的重复序列和与病毒基因组DNA复制相关的motif基序,对7个hrs中40个回文序列进行比对分析,发现其序列的核苷酸一致性高达90%以上.

The structure-function of homlogous region 5(hr5)from Spodoptera litura Nucleopolyhedrovirus Ⅱ(SpltNPVⅡ)was studied in this paper.The results showed that the length of hr5 is 389 bp consisting of three 64-bp imperfect palindromes,and each palindrome contains a PvuⅠ site in the center and one motif(CGATT)which related to the replication of genomic DNA of virus.A transent expression assay demonstrated that the expression of SpltNPVⅡ-ie1 promoter-driven luciferase gene was enhanced by hr5 in both infected and uninfected Spli221 cells.Real-time PCR confirmed that the hr5 could function as ori of viral DNA replication in infected cells with wild type virus as the helper virus.The study results indicated that SpltNPVⅡhr5 is bifunctional,having both ori and enhancer activities.

Using the Limonium sinense seeds from Dongying and Binzhou of Shandong Province as materials,the effects of seawater stress on its seed germination and seedling growth were reserched by using the germination potential,germination percentage,germination index and vigor index of seeds and the height and root length of seedlings.The results showed that the germination potential,germination percentage,germination index and vigor index of seeds from the two regions were all inhibited under seawater stress at the concentrations of 3％,25％,50％ and 67％ (volume fraction),so were the seedling height and root length.But under the stress of 6％ seawater,the seed vigor index increased,and the seedling growth was promoted.The root length was slightly inhibited under the stress of 12％ seawater.Almost all the seed germination of Limonium sinense from two regions was inhibited under the stress of 67％ seawater.Through comparison,the Limonium sinense from Binzhou was less influenced by seawater stress,and showed stronger salt resistant ability.