20％龙卷风水剂除治苗圃杂草药效试验

用20％龙卷风水剂进行除治苗圃杂草药效试验,结果表明：喷施20％龙卷风水剂200mL/667m^2后第7天,杂草除治效果为89．7％;喷施后第14天,杂草除治效果为95．6％;（杂）草鲜质量除治效果为96．1％,其药效要好于150mL／667m^2,与喷施20％克无踪水剂200mL／667m^2的药效相仿,且药效能持续20d,对苗木无影响,可在除治苗圃杂草上推广应用。     

8%黄腐酸与20%福克种衣剂复配对玉米种子活力的影响

[目的]探讨8%黄腐酸与20%福克种衣剂复配对玉米种子活力的影响。[方法]以农大108、郑单17、郑单958、安玉5号和洛玉1号5个玉米品种为试材,将8%黄腐酸与20%福克种衣剂按1∶1的比例复配后,按药种比1∶50对玉米种子进行包衣,采用室内发芽试验,研究复配后的种衣剂对玉米种子活力的影响。[结果]供试的5个玉米品种经复配种衣剂包衣后,与未包衣原品种对照相比,发芽率、发芽值和发芽指数均有不同程度的提高,分别提高了3.4%~5.9%、19.71%~27.86%和9.27%~16.45%。[结论]8%黄腐酸与20%福克种衣剂复配的种衣剂可提高玉米种子的发芽率、发芽值和发芽指数,从而提高玉米种子的活力。     

沙冬青A20／ANl锌指蛋白基因序列及表达分析

A20/AN1锌指蛋白普遍存在于真核生物中,在胁迫响应引起的信号传导过程中发挥着重要作用。本文利用生物信息学和RT-PCR方法从低温干旱胁迫的沙冬青叶片组织中分离锌指蛋白基因AmSTZF,该基因编码一条含172个氨基酸残基的多肽,含A20和AN1两个锌指蛋白保守结构域,属A20/AN1锌指蛋白。生物信息学分析显示该蛋白定位于细胞质中,具有磷酸化位点,参与细胞转录调控。RT PCR分析表明:低温和干旱胁迫处理的沙冬青叶片中,AmSTZF的表达增强,初步推测该基因与沙冬青低温、干旱胁迫响应相关。      

氮磷钾肥料不同用量对济麦20号产量效应的试验

通过采用三元二次通用旋转回归设计,对济麦20号优质专用小麦氮磷钾肥料不同用量产量效应的试验研究,产量≥7500kg/hm2的最佳施用尿素量为424.5～522.0kg/hm2、过磷酸钙为328.5～396.0kg/hm2、氯化钾为259.5～342.0kg/hm2。氮磷、氮钾、磷钾间交互作用显著,肥效相互促进。     

玉米秸秆低温高效降解复合菌系GF-20的菌种组成及降解稳定性

【目的】探索不同温度及pH条件对玉米秸秆低温高效降解复合菌系的玉米秸秆分解稳定性及菌群结构稳定性的影响,完善菌系培养方法,促进其应用开发利用。【方法】以低温高效降解复合菌系GF-20为研究对象,在10℃条件下连续继代培养45代、不同温度和pH条件下连续继代培养15代,分别获得多组不同代数（F）、不同温度（T）和pH（P）条件下的菌系。测定各复合菌系发酵液pH、玉米秸秆降解率及纤维素酶活,评价复合菌系的玉米秸秆分解稳定性;利用PCR-DGGE技术结合主成分分析法对菌群组成结构的稳定性进行研究。【结果】在10℃条件下经连续继代培养40代和在温度4-30℃、pH 6.0-9.0条件下继代培养获得的不同复合菌系发酵液pH均随发酵时间的延长趋近中性;玉米秸秆降解率在27.59%-32.53%,除F40显著高于F5外,其余无显著差异;纤维素酶活性呈高代菌系大于低代菌系,温度4-10℃和pH 6.0-9.0条件下,对复合菌系产酶有促进作用,纤维素酶活为1.34-1.84 IU·mL^-1;复合菌系的纤维素酶在较低的温度和较宽的pH范围内具有良好的温度和pH稳定性,酶促反应温度15-30℃和pH 4.0-9.0内仍保持80%以上的纤维素酶活力;复合菌系F5-F45、T4-T30和P6.0-P9.0的DGGE条带差异不显著,表明菌系的菌种组成稳定;而在偏酸（pH=4、5）和偏碱性（pH=10）条件下继代培养,复合菌系秸秆降解率和纤维素酶活均显著降低,菌种组成发生变化,进而影响性质与功能稳定性。PCR-DGGE共检测到18个条带,其中关键菌株分别为Bacillus licheniformis、Azonexus hydrophilusd、Azospira oryzae、Arobacter cloacae、Cellvibrio mixtus、Bacillus tequilensis、Clostridium populeti subsp. Mixtus和Clostridium xylanolyticum。【结论】复合菌系GF-20在温度4-30℃、pH 6.0-9.0条件下经过多代继代培养,仍然保持了较高的玉米秸秆分解活性和菌种组成稳定性,具有良好的应用前景。     

Cypermethrin inhibits egg development in the ixodid tick, Amblyomma hebraeum

The pyrethroid insecticide, cypermethrin (CyM), stimulates vitellogenesis in Ornithodoros moubata (an argasid tick) by stimulating the release of the normal vitellogenesis-inducing factor (a neuropeptide) and subsequent release of the vitellogenic hormone [19]. Here we examine the effects of CyM on egg development in the ixodid tick, Amblyomma hebraeum. Ovary weight, oocyte size, and vitellin content of the ovary were measured after CyM treatment; in partially fed ticks, none of these parameters were affected significantly. However, CyM treatment caused an inhibition of ovary development, as well as reduction of both hemolymph 20-hydroxyecdysone (20E; the vitellogenic hormone in this species) and vitellogenin (Vg)-concentrations in engorged ticks. In addition, the degree of salivary gland degeneration (which is triggered by 20E) was slightly reduced in CyM-treated engorged ticks. These results indicate that CyM acts differently in Amblyomma compared to Ornithodoros. Instead of stimulating vitellogenesis, CyM inhibits egg development perhaps in part as a result of inhibiting release of 20E.     

沉默蜕皮激素受体对雌性中黑盲蝽生殖力的影响

中黑盲蝽Adelphocoris suturalis是一种重要的农业害虫,主要为害棉花、果树和牧草等作物。昆虫保幼激素(juvenile hormone, JH)与蜕皮激素(molting hormone, 20E)是调控昆虫生殖的主要因素。本研究运用基因克隆、基因沉默(RNAi)、实时荧光定量PCR(qPCR)等技术研究蜕皮激素受体(ecdysone receptor, EcR)、超气门蛋白(ultraspiracle protein, USP)在中黑盲蝽生殖调控中的作用。结果表明,中黑盲蝽EcR基因的ORF全长1 413 bp,编码470个氨基酸。预测蛋白质分子量为53.65 kD,pI值为7.79。中黑盲蝽USP基因ORF全长1 209 bp,编码402个氨基酸。预测蛋白质分子量为44.99 kD, pI值为7.94。与对照相比,注射dsEcR、dsUSP后6～18 d的中黑盲蝽体内EcR基因、USP基因在转录水平分别被显著抑制;卵巢的挂卵量分别仅有对照组的31.5%、86.6%;单雌产卵量减少36.0%～80.4%,显著低于对照。EcR和USP基因沉默后,产卵前期与对照相比无显...     

Isolation and characterization of a 20 kD prolamin from kodo millet (Paspalum scrobiculatum) (L.): Homology with other millets and cereals

The homologus 20 kD prolamin from kodo millet and other minor millets viz. barnyard, little and foxtail millets, were purified using preparative gel electrophoresis and reversed phase high performance liquid chromatography (RP-HPLC). The amino acid composition of the purified 20 kD prolamin protein from different minor millets revealed higher content of glutamic acid, alanine, leucine and serine and lower quantity of lysine and methionine. They contain 55 to 58 percent of non-polar amino acids which make them more hydrophobic than other protein fractions. The total number of amino acid residues per polypeptide chain ranged from 152 to 155 based on theoretical calculation. Peptide mapping of the 20 kD prolamin hydrolyzed with trypsin gave fewer cleavage products than expected. The antigenic relationships among these minor millets and cereals viz. wheat, maize, rice, sorghum, finger millet and pearl millet were studied using the antibody raised against the 20 kD prolamin. Cross reactivity was seen in all the minor millets at the 20 kD region. But in barnyard and little millets lower molecular weight polypeptides also cross reacted with the antibody. Immunoblotting studies revealed that the prolamins from other cereals and millets are related to the 20 kD prolamin of kodo millet. Rice was the only common cereal that did not cross react immunologically with the antibody raised against 20 kD prolamin of kodo millet.     

荻草谷网蚜ABCG1基因的克隆及表达模式分析

荻草谷网蚜Sitobion miscanthi是严重威胁我国小麦生产安全的迁飞性害虫。蜕皮激素是参与蚜虫翅型分化调控的内激素, 在有翅成蚜体内保持高滴度, 且诱导后代产生更高比例的无翅蚜, 其进出靶细胞需要经过细胞膜上特定蛋白的转运。ATP结合盒转运蛋白家族G亚家族(ATP-binding cassette transporter G, ABCG)中的 ABCG1是通过跨膜转运昆虫类固醇、对蜕皮激素信号进行负调控的功能蛋白之一, 在蚜虫中尚未见报道。本文克隆了荻草谷网蚜ABCG1(SmisABCG1)基因, 并进行了序列比对、系统进化分析以及不同组织部位和发育时期表达模式分析。结果显示, SmisABCG1基因的开放阅读框全长为1 851 bp, 编码616个氨基酸, 含7个跨膜结构域, 符合ABCG蛋白家族典型结构特性, 基因登录ID:OP626323。昆虫间ABCG1较保守, 该蛋白系统进化关系与各自物种间亲缘关系的远近保持一致。其中, SmisABCG1与来自豌豆蚜、禾谷缢管蚜、棉蚜、花生蚜和雪松长足大蚜等的ABCG1氨基酸序列高度一致(>87%), 以上蚜虫聚为一支。与SmisABCG1亲缘关系最近的是豌豆蚜的ABCG1, 其次是半翅目的褐飞虱、白背飞虱和灰飞虱, 与膜翅目的新疆菜叶蜂、阿里山潜蝇茧蜂以及鞘翅目的赤拟谷盗、蜂箱小甲虫亲缘关系较远。该基因在伪胚胎和成蚜阶段高表达。包含伪胚胎的有翅、无翅成蚜整蚜SmisABCG1的转录水平无显著差异, 但其在来自有翅成蚜的伪胚胎中的转录水平高于无翅成蚜伪胚胎, 证实无翅成蚜自身的转录水平较高, 而有翅成蚜较低。进一步分析显示这一差异主要是无翅蚜胸部显著高表达所导致。基于该蛋白对蜕皮激素负调控, 与有翅成蚜转录水平低, 但蜕皮激素水平更高相符合。     

Frozen bread dough: Effects of freezing storage and dough improvers

This review focuses on the effects of freezing storage on the microstructure and baking performance of frozen doughs, and provides an overview of the activities of dough improvers, including emulsifiers, hydrocolloids and other improvers used in frozen dough applications. The overall quality of bread baked from frozen dough deteriorates as the storage of the dough at sub-zero temperatures increases due to several factors which are discussed. Lipid-related emulsifiers such as diacetyl tartaric acid esters of mono and diglycerides and sucrose esters employed as anti-staling agents, dough modifiers, shortening sparing agents, and as improvers for the production of high-protein bread have also been employed in frozen doughs. Hydrocolloids are gaining importance in the baking industry as dough improvers due to their ability to induce structural changes in the main components of wheat flour systems during breadmaking steps and bread storage Their effects in frozen doughs is discussed. Other dough improvers, such as ascorbic acid, honey and green tea extract, are also reviewed in the context of frozen doughs.