谷子白发病卵孢子重寄生真菌的分离鉴定

为了筛选出对谷子白发病卵孢子具有抑制作用的重寄生生防真菌,为谷子白发病生物防治提供一定的理论依据,研究利用诱捕法分离卵孢子表面的重寄生真菌,通过形态学对其进行初步鉴定,再对筛选出的具有潜在生防潜力的重寄生木霉菌进行分子生物学鉴定。结果表明,共分离到81株重寄生真菌;通过初步的形态学鉴定,将菌株分为4个属,分别是镰孢菌属(Fusarium)36株、青霉属(Penicillium)8株、木霉属(Trichoderma)27株、链格孢属(Alternaria)10株;结合形态学和分子生物学鉴定,从中筛选出对谷子白发病卵孢子具有潜在生防效果的重寄生真菌是木霉菌株哈茨木霉(Trichoderma harzianum)。     

Amoebic meningoencephalitis: axenic culture of naegleria

A medium consisting of 2 percent Bacto-Casitone (Difco) and 10 percent fresh horse serum in distilled water ensures axenic growth of two pathogenic isolates of Naegleria species.     

培养条件对大白菜无菌苗叶肉原生质体培养的影响

以市售栽培品种城青2号、高脚白大白菜无菌苗叶肉原生质体为材料,分别就激素、原生质体的培养密度、培养方式、多胺类物质对细胞分裂频率以及后期发育的影响进行了系统的研究.还探讨了在原生质体培养10天后加入提高了pH值的培养液来控制细胞褐化的可能性.     

中国指梗霉属Sclerospora分类研究

 本文报道指梗霉属Sclerospora中禾生指梗霉S. graminicola在国内新寄主植物和新分布,以及一新记录种法氏指梗霉S. farlowii,并讨论了本属分类变动问题。     

大孢指疫霉三个新变种的研究

 本文报道大孢指疫霉Sclerophthora macrospora可区分为3个变种,即大孢指疫霉水稻变种S.macrospora var.oryzae var.nov.,大孢指疫霉小麦变种S.macrospora var.triticina var.nov.和大孢指疫霉玉蜀黍变种S.macrospora var.maydis var.nov.,新变种有汉文和拉丁文描述及形态图,地理分布。     

室内饲养草间钻头蛛的生物学特性

[目的]研究室内饲养草间钻头蛛的主要生物学特性,探讨草间钻头蛛在室内饲养的可行性。[方法]在室内饲养条件下,观察不同温度下草间钻头蛛F1代的发育历期,2龄蜘蛛耐饥、耐旱能力,喂食不同食物的亚成蛛的捕食量和体重增长,F1代产卵数量、孵化率等指标。[结果]草间钻头蛛的发育历期随温度增加而缩短;2龄草间钻头蛛的饥饿历期平均为(8.94±2.79)d,耐旱历期平均为(1.30±0.57)d,耐饥、耐旱能力较亚成蛛、成蛛弱;喂食不同食物的的捕食量在2头左右,体重增长不同,饲喂果蝇和棉铃虫的亚成蛛较饲喂人工饲料增长快;草间钻头蛛F1代平均产卵4.85次,第1次产卵间隔平均为(6.62±1.56)d,以后产卵间隔缩短;F1代室内饲养孵化率为96.9%,较室外蜘蛛的自然孵化率高。[结论]室内饲养草间钻头蛛有一定的可行性。     

草间小黑蛛实验种群的生命表

在实验室条件下观察草间小黑蛛种群存活和繁殖动态,得出年龄特征存活率和繁殖率等数据,组建成年龄特征生命表和繁殖特征生命表.统计出有关种群各项参数,包括净繁殖率、世代平均历期、内禀增长能力、瞬时出生率和死亡率、周限增长率.双倍时间以及稳定年龄组配.应用Leslie矩阵模型模拟实验种群动态,并建立种群增长模型:N=98.7348e~(0.0386t)(23℃),N=100.1627e~(0.0482t)(27℃)。     

Nitrogen mustard: diminution of toxicity in axenic mice

Axenic, or germ-free, mice are more resistant to the delayed lethal effect of nitrogen mustard than normal mice. The resistance is most striking when mustard is administered at pH 2.0. The finding supports the hypothesis that intestinal bacteria play an important role in the systemic toxicity of nitrogen mustard.     

草间小黑蛛与桃一点叶蝉之间的数量关系

用相关分析法研究桃园草间小黑蛛在数量上对桃一点叶蝉的追随关系。结果表明,草间小黑蛛不管在桃树的水平方位还是垂直方位对桃一点叶蝉都有明显的追随关系。     

交叉变差函数表达的枣瘿蚊和草间小黑蛛的空间相关性

利用地统计学中的交叉变差函数法对枣园中枣瘿蚊及其天敌草间小黑蛛种群的空间相关性进行了研究.结果表明,5月21日至10月19日近5个月的枣树主要生育期阶段,除8月27日与9月21日草间小黑蛛与枣瘿蚊种群没有明显的空间相关性以外,其他各次尤其是5月30日与10月19日都充分表现出草间小黑蛛对枣瘿蚊在不同距离下的数量和空间的追随关系,再次证明草间小黑蛛是枣瘿蚊的优势种天敌.     

谷子白发病菌卵孢子重寄生真菌的分离与鉴定

为了从谷子白发病菌卵孢子上分离筛选出对谷子白发病具有生防潜力的重寄生真菌,通过石英砂振荡去除卵孢子表面附着物,利用孢悬液稀释点样和尖端菌丝分离法对重寄生真菌进行分离纯化,采用形态学与真菌r DNA-ITS序列分析对分离出的重寄生真菌进行鉴定。结果表明,谷子白发病菌卵孢子上重寄生r有层出镰孢菌(Fusarium proliferatum)、拟轮枝镰孢菌(Fusarium verticillioides)和半裸镰孢菌(Fusarium incarnatum)3种镰孢属真菌。     

禾谷炭疽菌腺苷酸环化酶的生物信息学分析

为了给禾谷炭疽菌新靶标药物的研究开发提供参考,以酿酒酵母的典型腺苷酸环化酶（AC）序列为基础,利用炭疽菌属蛋白数据库在线对其进行 Blastp 比对及关键词搜索,通过 SMART 对该菌典型AC 蛋白的保守结构域、理化性质、细胞信号肽、跨膜区结构以及二级结构等生物信息学进行分析,同时比较禾谷炭疽菌中典型 AC 氨基酸序列与其他物种同源序列的遗传关系。结果表明：禾谷炭疽菌中存在一个与酿酒酵母 Srv2同源的序列,命名为 CgCap1腺苷酸环化酶蛋白,该酶蛋白包含有530个氨基酸,基因序列长1906 bp 具有保守 CARP 结构域,等电点蛋白在5～6范围,属亲水性、不稳定蛋白,不含信号肽序列,定位于质膜上,二级结构中的β折叠所占比例较低,与同属于炭疽菌属真菌胶孢炭疽菌、西瓜炭疽菌的亲缘关系较近。     

Evaluation of Chinese rice varieties resistant to the root-knot nematode Meloidogyne graminicola

The root-knot nematode Meloidogyne graminicola, which is distributed worldwide, is considered a major constraint on rice production in Asia. The present study used the root gall index and number of nematodes inside the roots to evaluate resistance/susceptibility to M. graminicola in different subpopulations of Oryza sativa(aus, hybrid aus, indica, hybrid indica, temperate japonica, tropical japonica). Nematode development in highly resistant varieties was also evaluated. Analyses of randomly selected 35 varieties showed the number of M. graminicola nematodes inside the roots correlated very strongly(r=0.87, P≤0.05) with the nematode gall index, and the results from pot and field experiments revealed similar rankings of the varieties for resistance/susceptibility. Among the 136 tested varieties, temperate japonica displayed the highest gall index, followed by tropical japonica, indica, hybrid indica, aus, and hybrid aus. Zhonghua 11(aus), Shenliangyou 1(hybrid aus) and Cliangyou 4418(hybrid indica) were highly resistant to M. graminicola under both pot and field conditions. Further examination of nematode development suggested that compared to susceptible rice, M. graminicola penetrated less often into highly resistant varieties and more frequently failed to develop into females. The promising varieties found in the present research might be useful for the breeding of hybrid rice in China and for the further development of practical nematode management measures.     

Cultured cells of white pine show genetic resistance to axenic blister rust hyphae

Hypersensitive resistance to axenically cultured Cronartium ribicola was displayed by subcultured callus of Pinus lambertiana. Cellular resistance to a destructive rust disease can now be studied at the macromolecular level through use of cloned cells of both host and pathogen in a system amenable to emerging recombinant DNA technology.     

Tunisian Population of the Wheat Pathogen Mycosphaerella graminicola is Still Fully Sensitive to Strobilurin Fungicides

Mycosphaerella graminieola （anamorph： Zymoseptoria tritici） is the causal agent of Septoria tritici blotch, the most frequently occurring disease on wheat crops worldwide. A set of 163 monoconidial isolates of this fungus were sampled in 2012 from five geographical locations of Tunisia （Bizerte, B6ja, Kef, Jendouba and Siliana） in order to examine the status of strobilurin resistance of M. graminicola in this country. The resistance was assessed by using PCR-based mismatch mutation assay that determined the cytochrome b substitution G143A responsible for strobilurin resistance. All isolates were found sensitive since they possessed the wild-type allele G143 conferring sensitivity. This study confirms previous reports on the fungus in Tunisia and reveals that the Tunisian population of M. graminicola remains fully sensitive to strobilurin fungicides. An appropriate management of strobilurin applications in Tunisia is thereby recommended to prevent local development and widespread of resistance, as in Europe, where pathogen populations are fully resistant to strobilurins today.     

4种杀虫剂对草间钻头蛛和三突花蛛的毒力测定

蜘蛛在控制害虫和发展无公害农业中起着重要的作用[1 ] 。草间钻头蛛Ｈｙｌｙｐｈａｎｔｅｓｇｒａｍｉｎｉｃｏｌａ (Ｓｕｎ ｄｅｖａｌｌ)和三突花蛛Ｍｉｓｕｍｅｎｏｐｓｔｒｉｃｕｓｐｉｄａｔｕｓ(Ｔａｂｒｉｃｉｕｓ)是农田中的优势种蜘蛛[2 ,3] 。化学防治为作物带来增产的同时 ,也给蜘蛛等害虫天敌造成了危害[4] 。为减少农药对天敌的伤害 ,应尽量选用对害虫高效而对天敌低毒或无毒的农药品种 ,因此测定农药对蜘蛛的毒力 ,对于保护天敌以及科学合理地使用农药具有重要的意义。本文采用点滴法测定了 4种杀虫剂对草间钻头蛛和三突花蛛…     

植物组织培养中降低培养基成本的研究

在马铃薯、菊花和满天星的发根阶段研究了用自来水代替蒸馏水、白糖代替蔗糖的可行性．结果表明：马铃薯、菊花和满天星培养苗的生长在蔗糖与白糖、蒸馏水与自来水的处理间无显著性差异，因此规模化生产上配制培养基时用白糖取代蔗糖，自来水取代蒸馏水完全可行．