赖氨酸修饰对梯棱羊肚菌黑色素结构和理化特性的影响

为了进一步提高梯棱羊肚菌黑色素的提取率及溶解性,本试验采用单因素、Plackett-Burman试验、响应面试验对纤维素酶-超声波协同提取梯棱羊肚菌黑色素的提取工艺进行优化研究。通过赖氨酸修饰,并对修饰前后的梯棱羊肚菌黑色素进行结构表征、理化性质及稳定性研究。结果表明,在NaOH浓度为1.54 mol/L,纤维素酶添加量为20 mg/g,纤维素酶酶解时间为78.6 min,料液比为1:30,酶解温度为40 ℃,超声时间为80 min条件下提取的梯棱羊肚菌黑色素最优。未修饰的梯棱羊肚菌黑色素不溶于水,色价值为480.24,修饰后的黑色素溶解度为1 016 g/L,色价值为1 771.18,比未修饰的黑色素在溶解性、色价值方面均有所提高。此外,在不同的温度、光照、pH条件下,修饰前后的梯棱羊肚菌黑色素均比较稳定。以上研究结果为梯棱羊肚菌黑色素的高效提取及其产品的开发利用奠定了理论基础。     

普通小麦-柔软滨麦草易位系M97抗条锈基因的遗传分析和分子作图

为了明确M97抗条锈性遗传规律,在苗期用7个小麦条锈菌系对M97与感病品种铭贤169的杂交后代F1、F2、F3和BC1代进行抗条锈性遗传分析,并对M97抗Sun11-4的抗条锈基因进行SSR分子标记。M97对Sun11-4和Sun11-11的抗病性均由1对显性基因控制,对CY29、CY30、CY33的抗病性由1显1隐2对基因共同控制,对CY31的抗病性由2对显性基因独立或重叠作用控制。以接种Sun11-4的F2代分离群体构建作图群体,筛选到Xwmc222、Xwmc147、Xbarc229和Xwmc339等4个与抗病基因连锁的SSR标记,其遗传距离分别为3.4、4.8、7.6和12.1 cM。将该抗病基因定位于小麦1DS染色体,且该基因不同于已知的抗条锈基因,暂命名为YrM97。用YrM97两侧遗传距离最近的2个标记Xwmc222和Xwmc147对42个黄淮麦区主栽小麦品种进行分子检测,仅有9.5%的品种具有与YrM97相同的标记位点。     

Penetration, Development and Emigration of Juveniles of the Nematode Meloidogyne arenaria in Myrobalan Plum (Prunus cerasifera) Clones Bearing the Ma Resistance Genes

Penetration, development and emigration of M. arenaria in the roots of three Myrobalan plum (Prunus cerasifera) clones genetically characterized for their resistance to root-knot nematodes (RKN) were studied during the 10 (penetration) and 15 (emigration) days following the date of inoculation (D) of 2500 juveniles (J2s) per plant into the soil. Miniaturized tests were conducted on the two resistant clones P.2175 (Ma1 gene) and P.1079 (Ma2 gene) and the susceptible clone P.2032 (recessive for both genes), obtained from micropropagated plantlets and grown in mini-containers under controlled conditions at 25°C in a growth chamber. For penetration and development studies, nematodes in the roots were recovered by the acid fuchsin-lactophenol staining technique. Equivalent numbers of J2s were recovered in all the clones at D+1 and D+2. Subsequently, the numbers increased rapidly in P.2032 and were significantly different from those in P.1079 and P.2175 that remained at a low level. No swollen larvae were observed in the resistant clones. In P.2032, the first swollen larvae were observed at D+4, the first females were observed at D+12, whereas the first females with attached egg sacs and the first new-generation J2s were obtained between D+21 and D+28. Our data suggest that the resistance phenomenon does not act on the very early nematode penetration but acts later by preventing feeding-site induction and development into the third-stage. For emigration studies, plants in which J2s had been allowed to penetrate for two days (from D to D+2) were washed free of soil, repotted and then, after various periods of growth, soil-free roots were placed under a mistifier to evaluate the numbers of emigrating individuals. Emigration of J2s from the roots occured mainly from D+2 to D+4 in all the genotypes and was very limited from D+4 to D+10. There was no significant differences in the number of emigrated juveniles between the resistant and susceptible clones, indicating that emigration cannot explain the difference in the numbers of nematodes recovered in the roots.     

北美栅锈菌和松杨栅锈菌可视化检测体系建立

目的 为实现北美栅锈菌和松杨栅锈菌快速有效的鉴别及鉴定。 方法 本研究根据两种锈菌的28SrDNA基因序列设计若干组LAMP引物。经筛选得到的引物以北美栅锈菌、松杨栅锈菌、图拉斯叉钩丝壳菌、芍药白粉菌、梨胶锈菌、羊肚菌、金针菇的基因组DNA为模板进行LAMP反应并完成特异性检测;首先建立初始LAMP反应体系,再进一步优化LAMP反应体系的组分和反应条件,加入羟基萘酚蓝实现可视化检测;最后确定检测体系灵敏度。 结果 表明,筛选出的引物具有特异性;25 μL北美栅锈菌LAMP检测体系最佳Mg2＋浓度为6 mmol·L−1,最佳内外引物比例为8：1,最佳dNTPs浓度为1.2 mmol·L−1;同样地,25 μL松杨栅锈菌LAMP检测体系最佳Mg2＋浓度为4 mmol·L−1,最佳内外引物比例为6：1,最佳dNTPs浓度为1 mmol·L−1。加入160 μM羟基萘酚蓝（HNB）可清晰地指示反应结果,两种检测体系在61 ℃条件下,分别反应30 min和40 min可实现目视判断结果,且灵敏度分别可达34 fg·μL−1和60 fg·μL−1。 结论 通过建立两种锈菌的可视化LAMP-HNB检测体系可实现对北美栅锈菌和松杨栅锈菌进行区分及鉴定,为快速鉴定和区分重要杨树锈病提供了技术支撑和实践参考。     

橡胶树热研88-13品种珠心易碎愈伤组织诱导及其胚状体发生

以橡胶树热研88-13品种的幼嫩种子的珠心组织为材料,诱导出胚性愈伤组织。对胚性愈伤组织诱导培养基、继代培养基中不同的影响因素如植物生长调节剂的种类和浓度、钙离子浓度等进行了研究,筛选到了合适的影响因素。经过连续5个月的继代选择培养,逐渐诱导出易碎的胚性愈伤组织。对易碎胚性愈伤组织进行了长期继代培养。组织学切片证明长期继代培养的愈伤组织维持了胚性的状态。取继代培养了2年多的橡胶树热研88-13品种的珠心易碎胚性愈伤组织诱导胚状体,得到了186个胚状体,正在诱导植株再生。     

60Co-γ射线辐射马铃薯块茎M2代群体的诱变效应

[目的]研究60Co-γ射线的不同辐射剂量对马铃薯块茎M2代群体的诱变效应。[方法]以云薯2号和鄂马铃薯5号为试材,采用60Co-γ射线的4种辐射剂量（5、10、15、20GY）分别对2个马铃薯品种的休眠块茎进行辐射诱变,分别测量2个马铃薯品种M2代叶片的叶绿素含量、干物质、淀粉含量以及产量等农艺性状,研究60Co-γ射线的不同辐射剂量对马铃薯M2代群体的诱变效应。[结果]不同辐射剂量对同一马铃薯品种M2代主要农艺性状产生的变异程度不同;相同辐射剂量对不同马铃薯品种M2代主要农艺性状所产生的变异程度不同。60Co-γ射线诱变改良个别性状（早熟、抗病性、高产、叶绿素含量）较有效,60Co-γ射线诱变马铃薯的适宜照射剂量为10～20GY,从2个马铃薯品种M2代中共单选出41个优株系。[结论]对马铃薯进行辐射诱变是一种有效的育种手段,但大多数突变是隐性突变,辐射诱变育种难度较大。     

薄荷和留兰香香气成分的分析与比较

为研究薄荷(Mentha haplocalyx)、留兰香(M.Spicata)两种唇形科薄荷属植物的香气成分,采用动态顶空法采集两种植物释放的香气后,利用自动热脱附-气相色谱/质量色谱联用技术(ATD-GC/MS)对香气成分进行了鉴定。结果表明,在薄荷香气中鉴定出44种成分,远高于留兰香的26种。这些物质分别属于萜烯、醛、酮、脂肪烃、酯、醇、苯形烃,及其他类物质。且留兰香香气释放量则显著高于薄荷,约为薄荷的1.6倍。在两种植物的香气中,萜烯类化合物数量和释放量均为最高,是香气的主要组成种类。d-柠檬烯和2-乙基-1-己醇在薄荷和留兰香中均表现出较高的释放量,可初步推断它们是薄荷、留兰香香气的主要成分。     

Generation of mouse monoclonal antibodies specific to tilapia immunoglobulin using fish immunoglobulin/BSA complex for monitoring of the immune response in Nile tilapia Oreochromis niloticus

The simple immunoprecipitation method was used to isolate tilapia immunoglobulin (Ig) for immunization in order to produce monoclonal antibodies (MAbs) specific to tilapia Ig. First, the tilapia antiserum against bovine serum albumin (BSA) was prepared by peritoneal injection of BSA into tilapia, and the tilapia anti‐BSA antiserum was used to precipitate BSA to form the Ig/BSA immune complex. The Ig/BSA immune complex was then injected into Swiss mice for hybridoma production. After fusion, three hybridoma clones producing MAbs specific to the tilapia antibody were selected by dot blot and Western blot. All MAbs (101A, 59G, and 11A) were bound specifically to the heavy chain of immunoglobulin M (IgM). The MAbs 101A and 59G demonstrated twofold higher affinity than MAb 11A and the commercialized antibody. However, MAbs 11A could also bind to the heavy chain of IgM in Asian seabass, Lates calcarifer, as well. These MAbs can be used to monitor the immune responses of individual fish by indirect ELISA upon exposure to various antigens.     

氯化钙体系制备的褐藻酸钙凝胶特性的研究

采用氯化钙体系制作的褐藻酸钠凝胶,其性能受氯化钙浓度、温度及褐藻酸钠的甘露糖醛酸(M)及古罗糖醛酸(G)的比值(即M/G)影响较大。当氯化钙溶液的温度为50℃、浓度为2.0%时,凝胶的性能最佳;高G的褐藻酸钙凝胶的拉伸强度优于高M的,但是吸水性能却不如高M的褐藻酸钙凝胶。通过红外光谱分析褐藻酸钠成凝胶前后结构变化,主要是-OH峰位置向高波数方向偏移以及C-H伸缩振动变弱,这是褐藻酸钠与Ca2+之间发生交链的结果。     

黄鳝血清、肠黏液免疫球蛋白的分离纯化及部分特性分析

采用硫酸铵盐析、SephadexG-200凝胶层析等方法从黄鳝血清和肠道黏液中分离纯化出黄鳝血清和黄鳝肠黏液免疫球蛋白。SDS—PAGE分析表明,二者的理化性质相同;经β-巯基乙醇处理后解离形成重链和轻链两个亚单位,分子量分别为74kD和29kD。试验结果表明,黄鳝血清和肠黏液中存在免疫球蛋白,二者具有相同的层析和SDS-PAGE电泳特性。