可视化LAMP快速检测猪伪狂犬病毒

为快速检测猪伪狂犬病毒(PRV),利用PRV DBP基因上的一段序列设计并合成3对LAMP引物,采用一种新的荧光染料——罗丹明B衍生物作指示剂,该指示剂在反应前加到反应缓冲液里,通过优化反应条件,建立了可视化LAMP快速检测PRV的方法。结果表明,63℃下恒温反应40min可得到肉眼可视结果,颜色变成蓝色判定为阳性,仍然保持紫色判定为阴性,可视化LAMP结果与电泳结果一致。建立的可视化LAMP方法可以快速、直观、准确地检测PRV。     

苯胺及其部分衍生物对Bt亚种HD-1的毒理作用

以苏云金芽孢杆菌(Bacillus thutingiensis Berlinert)亚种HD-1菌株为指示菌,采用比浊法测定其生长曲线,研究苯胺、邻氯苯胺、间氯苯胺、对氯苯胺对HD-1的生长抑制毒性,应用等比法分别测定每种化合物的剂量-效应数据,采用最小二乘拟合进行非线性拟合.结果表明,苯胺、邻氯苯胺、间氯苯胺和对氯苯胺对标准菌HD-1的24 h EC50分别为:0.034 901、0.004967、0.004797、0.004 686 mol/L,苯胺及苯胺衍生物对HD-1的毒性从小到大顺序为苯胺、邻氯苯胺、间氟苯胺、对氯苯胺.     

Enhancement of fungicidal and insecticidal activity by reductive alkylation of chitosan

A series of N-alkyl chitosan (NAC) derivatives were synthesized using a reductive alkylation reaction to examine their fungicidal and insecticidal activity. The chemical structures were characterized by IR and (1)H NMR spectroscopy, and the degree of substitution (DS) ranged from 0.02 to 0.37. Their fungicidal activity was evaluated against the grey mould Botrytis cinerea Pers ex Fr (Leotiales: Sclerotiniaceae) and the rice leaf blast pathogen Pyricularia grisea Sacc [Teleomorph: Magnaporthe grisea (Hebert) Barr] by a radial growth bioassay. It was of interest that most of the NAC derivatives were more active against both fungi than chitosan itself. The most active derivative was N-(2,2-diphenylethyl)chitosan with EC50 values of 0.031 and 0.23 g L(-1) against B. cinerea and P. grisea respectively. In addition, some derivatives, at higher concentrations up to 1.0 g L(-1), inhibited the mycelial growth and spore formation of P. grisea. Bioassays against larvae of the cotton leafworm, Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) with the NAC derivatives at a rate of 5.0 g kg(-1) in artificial diet demonstrated that N-(3-phenylbutyl)chitosan was the most active compound. In addition, N-propylchitosan, N-undecanylchitosan and N-(3-phenylpropyl)chitosan derivatives strongly inhibited larval weight gain in S. littoralis, with respective reductions of 76, 66 and 65% after 4 days of feeding on treated diet.     

饲粮瘤胃降解蛋白质水平对哈萨克育肥羊瘤胃微生物氮合成量和氮沉积量的影响

本试验旨在研究哈萨克羊育肥羊在以低质粗饲料条件下,增加饲粮瘤胃降解蛋白质(RDP)水平对瘤胃微生物氮(MN)合成量和氮沉积量的影响。选取体重为(30.0±2.8)kg的哈萨克羊育肥羊公羔3只作为试验动物,分别饲喂RDP水平为7.94%(TMR1)、9.02%(TMR2)、10.10%(TM R3)的3种饲粮。按照3×3拉丁方试验设计进行试验,共3期,每期预试期10 d,正试期5 d。全部收集粪尿,测定尿中嘌呤衍生物(PD)排出量、瘤胃MN合成量和转化效率。结果表明:3种饲粮的干物质及有机物的采食量及表观消化率均无显著性差异(P0.05),但TM R3的氮沉积量、尿中PD排出量及瘤胃M N的合成量均显著高于TM R1和TM R2(P0.05)。饲粮RDP水平与MN合成量/瘤胃表观可消化有机物(RADOM)采食量之间存在显著的正相关(R2=0.999 4,P=0.010 9)。M CP的转化效率不受饲粮RDP水平影响(P0.05)。结果提示,低质粗饲料条件下,将饲粮RDP水平由7.94%提高至10.10%,能够提高哈萨克育肥羊氮沉积量,促进瘤胃MCP的合成,但未能显著提高MCP的转化效率。     

异长叶烷酮合成新型喹唑啉衍生物的研究

以异长叶烷酮为原料,叔丁醇作溶剂,通过缩合得到7-(4'-氟苯亚甲基)异长叶烷酮(FBI),再与盐酸胍环化合成了喹唑啉衍生物4-(4'-氟苯基)-6,6,10,10-四甲基-6a,9-桥亚甲基-5,6,6a,7,8,9,10,10a-八氢苯并[h]喹唑啉-2-胺(FBQ),考察了催化剂种类及用量、反应温度、反应时间以及FBI与盐酸胍的物质的量比对环化反应的影响,并通过正交试验法确定了环化反应的适宜工艺条件。最优工艺条件为:以叔丁醇钾为催化剂,n(t-Bu OK)∶n(FBI)为2.9∶1,反应温度75℃,反应时间14 h,FBI与盐酸胍的物质的量比为1∶4,产物得率达到79.51%。采用FT-IR、MS、1H NMR、13C NMR及X射线单晶衍射等分析手段,确定了产物的结构及空间构型。通过X射线单晶衍射法测定表明,化合物属于三斜晶系,P-1空间群,晶包参数a=0.660 85(9)nm,b=1.175 27(16)nm,c=1.340 65(17)nm,α=86.229(3)°,β=83.094(4)°,γ=77.558(4)°,V=1.008 6(2)nm3,Z=2,DC=1.203 g/cm3,F(000)=392,Mr=365.48,μ=0.078 mm-1,R=0.099 3,wR=0.156 5。     

三烃基锡氨基酸酯的合成与生物活性

用三烃基锡氧化物和氢基酸反应，合成出相应的三烃基锡氨基酸酯，并对这些化合物进行了生物活性普筛测定。结果表明：氨基酸锡酯在病害，虫害，草害和植物激素４方面均有活性，病害和草害活性尤其显著。     

稀土（Nd,Pr）（Ⅲ）双酞菁衍生物的合成,表征和成膜性

本文介绍四种新的稀土（Ｎｄ，Ｐｒ）（Ⅲ）双酞菁衍生物合成：八－４－（四氢糖氧基）钕（Ⅲ）（Ａ）；八－４－（β－萘氧基）钕（Ⅲ）（Ｂ）；八－４－（２，４－二特戊基苯氧基）钕（Ⅲ）（Ｃ）：八－４－（２，４－二特戊基苯氧基）镨（Ⅲ）（Ｄ）；并通过元素分析红外光谱，核磁共振谱加以确认。     

Utilization of tom thumb source of pre-harvest sprouting tolerance in a wheat breeding programme

Summary Segegating populations of the cross Tordo (a spring white-grained Tom Thumb derivative) and Tr 454-16 (a spring white-grained Sonora-Gabo derivative) were studied for plant height, apparent -amylase synthesis (AAS) and response to gibberellic acid. Means, variances and heritabilities for these characters were computed and their association was studied by computing correlation coefficients. Plant height showed high heritability while AAS and response to GA₃ showed moderate heritability. Plant height was positively correlated with AAS and response to GA₃. The results pointed out the importance of using Tom Thumb as a source of pre-harvest sprouting tolerance in a wheat breeding programme, particularly in areas where wheat breeding is restricted to evolving white-grained cultivars.     

Components of resistance to late leaf spot and rust among interspecific derivatives and their significance in a foliar disease resistance breeding in groundnut (Arachis hypogaea L.)

Late leaf spot (LLS) and rust cause substantial yield losses and reduce the fodder and seed quality in groundnut (Arachis hypogaea L.). Adoption of resistant cultivars by the semi-arid tropic farmers is the best option to overcome yield losses. Knowledge on components of resistance to these diseases should facilitate the development of groundnut cultivars with enhanced resistance to LLS and rust. The objectives of the experiments were to study the genetic variability and relationships among components of resistance to LLS and rust, and assess their significance in disease resistance breeding. Fifteen interspecific derivatives for LLS and 14 for rust and a susceptible control, TMV 2, were evaluated in a randomised complete block design with two or three replications under greenhouse conditions. The experiments were repeated twice. Genotypic differences were highly significant for all the traits studied. Resistance to LLS is due to longer incubation and latent periods, lesser lesions per leaf, smaller lesion diameter, lower sporulation index, and lesser leaf area damage and disease score. Selection based on components of resistance to LLS may not lead to plants with higher retained green leaf area. The remaining green leaf area on the plant should, therefore, be the major selection criteria for resistance to LLS in breeding programs. Resistance to rust is due to longer incubation and latent periods, fewer pustules per leaf, smaller pustule diameter, lower sporulation index, and lesser leaf area damage and disease score. Rust resistant components appear to work additively, therefore, selection based on resistance components together with green leaf area retained on the plant should be the basis of selecting for resistance to rust in breeding programs. ICGV 99005, 99003, 99012, and 99015 for rust and ICGV 99006, 99013, 99004, 99003, and 99001 for LLS are the better parents for use in resistance breeding programs. This revised version was published online in July 2006 with corrections to the Cover Date.     

Assessment of genetic diversity among selected groundnut germplasm. I: RAPD analysis

Assessment of genetic diversity in a crop species is prerequisite to its improvement. The use of germplasm with distinct DNA profiles will help to generate genetically diversified breeding populations. The aims of the present experiment were to study molecular diversity among selected groundnut accessions and identify those with distinct DNA profiles for mapping and genetic enhancement. Twenty‐six accessions and eight primers of a 10‐mer were selected for random amplified polymorphic DNA assay. The genetic similarity (S_ij) ranged from 59.0% to 98.8%, with an average of 86.2%. Both multidimensional scaling and unweighted pair‐group method with arithmetic averages (UPGMA) dendrograms revealed the existence of five distinct clusters. However, this classification could not be related to known biological information about the accessions falling into different clusters. Some accessions with diverse DNA profiles (ICG 1448, 7101, and 1471, and ICGV 99006 and 99014) were identified for mapping and genetic enhancement in groundnut.