酵母菌对草莓果实防腐保鲜的效果研究

以新鲜草莓为材料,研究1×106、1×107、1×108 cfu/mL不同浓度的柠檬形克勒克酵母菌悬液浸泡对草莓品质指标的影响,以探讨生物防腐剂对草莓果实防腐保鲜的效果.结果表明:1×108 cfu/mL的酵母菌悬液处理对抑制草莓腐烂的效果最好,能够推迟草莓的后熟,有效保持果实的品质.     

虫霉目新记录属及新记录种

本文报道了虫霉目的1个新记录属和1个新记录种。新记录属采自太白山原始林斑腹蝇尸,只产生外生休眠孢子,外壁桔黄、刺状,不能脱落,未见分生孢子,只能鉴定为斯魏霉属Strongwellsea。新记录种布伦克虫疠霉Pandora blunckii(Lakon etZimmermann)Humber.系宁夏六盘山林区松线小卷叶蛾流行主要病原,分生孢子倒拟卵形,假根单菌丝状,末端有盘状固着器。尖突巴科霉Batkoa apiculata(Thaxter)Humber.分生孢子为球状,乳突端部有尖突,为西北地区首次报道。     

转红树总DNA紫花苜蓿T1代耐盐株系的生理生化特性分析

以花粉管通道法转红树总DNA紫花苜蓿阿尔冈金T₁代耐盐植株幼苗为材料,经300 mmol/L NaCl处理后,测定叶绿素、脯氨酸、丙二醛含量和抗氧化酶活性等耐盐相关生理生化指标。结果显示,转基因株系叶绿素含量下降0.09~0.29倍,而对照植株下降0.32倍;转基因株系脯氨酸含量升高1.2~4.2倍,对照植株的脯氨酸升高0.9倍;转基因株系丙二醛含量升高0.15~0.29倍,对照植株的丙二醛含量升高0.36倍;转基因株系超氧化物歧化酶活性升高0.20~0.25倍,对照植株的超氧化物歧化酶活性升高0.19倍;转基因株系过氧化物酶和过氧化氢酶活性分别是对照的1.6~5.6倍和1.2~1.3倍。转基因株系表现出耐盐植物的生理生化特性。     

红树叶蛋白质样品制备方法的比较及其双向电泳分析

采用水溶液提取法(磷酸盐缓冲液系统)、三氯乙酸-丙酮沉淀法和Phenol改良提取法,对红树叶进行蛋白质提取,并比较分析了这3种方法的蛋白质提取率、完整性、溶解性等。结果表明:水溶液提取法得到的是胶状沉淀,基本为多糖类物质,蛋白质含量很低;三氯乙酸-丙酮沉淀法提取的蛋白质纯度较高,但双向电泳背景最低,提取率较低,蛋白质的完整性差;Phenol改良提取法的蛋白质提取率高,约为三氯乙酸-丙酮法的10倍,双向电泳凝胶背景比三氯乙酸-丙酮沉淀法要深,蛋白质的完整性好,能够被电泳分离的蛋白质点是三氯乙酸-丙酮沉淀法的7倍左右。Phenol改良提取法在蛋白质的提取率以及完整性方面远远高于其他2种蛋白质提取方法。     

The determination of the age and growth of SE Asian mangrove seedlings from internodal counts

The occurrence of periodic changes in the length of the internodes of the seedlings of SE Asian mangrove species (Rhizophora apiculata, Avicennia alba, and Sonneratia caseolaris) growing in the Pak Phanang estuary (Nakhon Si Thammarat, SE Thailand) was confirmed. The annual nature of these periodic changes was verified through comparisons with the observed average number of internodes produced by plants tagged for one year. The cycles in the sequence of internodal length of the seedlings had an average (± SE) period of 16.0 ± 0.78 internodes for Avicennia alba, 25.0 ± 1.2 internodes for Sonneratia caseolaris, and 8.29 ± 0.40 internodes for Rhizophora apiculata. These values are remarkably close to, and not significantly different (ttest, P > 0.05) from the average (± SE) annual number of internodes of 17.6 ± 0.8 for Avicennia alba, 28.8 ± 2.1 for Sonneratia caseolaris, and 8.03 ± 0.36 for Rhizophora apiculata produced in a year by tagged plants. In addition, the average (± SE) growth of the tagged plants was 0.39 ± 0.018cm day^-1 for Avicennia alba, 0.24 ± 0.015cm day^-1 for Sonneratia caseolaris, and 0.091 ± 0.0036cm day^-1 for Rhizophora apiculata. These estimates were very close to those (0.45 ± 0.06cm day^-1 for Avicennia alba, 0.32 ± 0.01cm day^-1 for Sonneratia caseolaris, and 0.13 ± 0.005cm day^-1 for Rhizophora apiculata) derived as the product of the mean number of internodes produced per day, calculated from the inferred number of internodes produced per year, and the mean length of the internodes of the plants. These findings indicate that the use of regular, annual changes in the length of the internodes of mangrove seedlings can be used reliably to determine their age and to estimate their growth rate.     

柠檬形克勒克酵母对柑橘的防腐保鲜技术试验

研究了106CFU·mL-1的生防菌34-9悬浮液对温州蜜柑尾张果实防腐保鲜的效果.贮藏90d后,生防菌34-9酵母菌悬浮液能够有效的抑制尾张果实青霉、绿霉和蒂腐病等贮藏病害的发生;控制它们的果皮腐烂发病率为5.5%,其防腐效果与低剂量化学药剂(如施保克)防腐效果相当;控制尾张的失水率为2.53%,与目前所使用的保鲜剂2,4-D保鲜效果相当.     

柑橘青、绿霉病高效拮抗菌34-9的筛选及其特性研究

 从柑橘园根际土壤中分离到1株对柑橘青、绿霉病菌有强烈拮抗作用的酵母菌株（34-9），在活体及离体试验中其抑制病菌的作用均较强，在柑橘果实表面接种6 d未发病。其上清液和灭菌液对柑橘青、绿霉病菌没有抑制作用，初步断定该菌株不产生抗生素。经形态特征和生理生化检测，确定其为柠檬形克勒克酵母菌（Kloeckera apiculata）。扫描电镜观察表明，酵母菌株（34-9）对柑橘青、绿霉病菌直接作用，可观察到酵母菌株（34-9）紧紧包围柑橘青、绿霉病菌菌丝或附着吸附在柑橘青、绿霉病菌菌丝上，最终使柑橘青、绿霉病菌菌丝浓缩，菌丝畸形。