大豆重迎茬减产的原因及农艺对策研究——重迎茬大豆的根系分泌物与根茬腐解物

通过连续8年在黑龙江省6个生态区9个固定轮作场圃综合试验,试验区专项研究,框区、盆栽试验,实验室分析,以及大量的大面积生产调查,发现大豆重迎茬种植根系分泌物增加,且对大豆生长发育及土壤微生物区系有不利的影响,同时也影响到土壤微量元素的活化;根茬腐解物对大豆的生长和根系活力都有不利的影响,并使大豆的产量明显降低。研究结果表明,根系分泌物和根茬腐解物对重迎茬大豆的生长发育和产量有一定的影响,它们也是造成大豆重迎茬减产的一个原因。     

基于聚类分析的美洲黑杨叶片抗螨性化学物质研究

对8种1年生美洲黑杨杂种无性系叶片中的化学物质进行了萃取分离,并对分离物进行了聚类分析.结果表明:表型抗螨的无性系乙酸乙酯层中萃取物质的含量与表型感螨的无性系中的含量差异显著;生物活性检测结果证明,乙酸乙酯层萃取物对螨的驱赶性和毒杀性明确,且美洲黑杨叶片中化学物质的差异性对其抗螨能力有影响.在优质美洲黑杨抗螨性品种的选...     

Effects of marine fungal metabolites 1386A from the South China Sea on proliferation,apoptosis and mitochondrial membrane potential in gastric cancer cell line MCG-803

AIM: To investigate the effects of marine fungal metabolites 1386A from the South China Sea(1386A) on gastric cancer cell line MCG-803.METHODS: The effects of 1386A on cell viability and cell growth were detected by MTT method and colony-forming assay, respectively. The changes of cell cycle, cell apoptosis and mitochondrial membrane potential were determined by flow cytometry.RESULTS: The IC₅₀ of cell viability on MCG-803 cells after treated with 1386A for 24 h, 48 h and 72 h was 29.70 μmol/L, 14.07 μmol/L or 13.47 μmol/L, respectively. The IC₅₀ of the cell growth on MCG-803 cells after treated with 1386A for 48 h was 3.27 μmol/L. After treated with 1386A for 48 h, the MCG-803 cells in S stage was increased from 25.6% to 56.8%. After treated with 1386A for 24 h, the early apoptosis of MCG-803 cells was increased from 3.34% to 8.39%, and the mitochondrial membrane potential of MCG-803 cells was decreased by 56.26%.CONCLUSION: 1386A has an inhibitory effect on the cell growth in MCG-803 cells through the mitochondrial pathway.     

黑曲霉真菌诱导子对喜树培养细胞喜树碱积累的影响

以黑曲霉提取物作为真菌诱导子,研究其对提高喜树悬浮培养细胞的生长和喜树碱产量的影响。结果表明:终浓度40 mg/L的诱导子在细胞培养的第14天加入,细胞干重在第26天达到最大量31.5 g/L,是未处理的细胞干重的1.2倍;喜树碱产量在第29天达到最大值13.6mg/L,是对照产量的6.0倍,没有受到诱导处理的细胞干重和喜树碱产量都在第20天达到最大值。与真菌诱导子刺激提高细胞生长和喜树碱生物合成相对应的是,诱导刺激的培养细胞表现出较高的细胞活力,培养基中糖类的消耗量也随之增加。     

中医不同治法对大鼠心肌缺血再灌注 损伤后细胞凋亡的影响

〔摘要〕目的观察中医不同治法补气、活血、化痰对大鼠心肌缺血再灌注(( I/R)诱导细胞凋亡及凋亡相关基因 Bcl-2,Bax和氧自由基含量的影响、方法建立大鼠动脉粥样硬化在体心肌缺血再灌注模型,采用原位末端TUNEL 法检测心肌细胞凋亡指数(AI),链酶亲和素一生物素一酶复合物(}BAB(7)免疫组化法检测凋亡相关基因Bcl-2,Bax蛋 白表达,常规方法检测丙二醇(MDA)含量、超氧化物歧化酶(80D)活性、结果与I/R组比较,中医补气、活血、化痰 法均能降低AI,有效清除氧自由基,差异有统计学意义(P<0.01);与I/R组比较,其中活血法和化痰法均能上调 Bcl-2表达、卜调Bax表达,差异有统计学意义(P<0.01),最终达到保护I/R心肌的目的〔结论中医不同治法补 气、活血、化痰可能通过不同途径预防I/R心肌细胞发生凋亡.从而对I/R心肌具有保护作用、     

墨兰和蝴蝶兰镰刀菌病害的鉴定

对广东栽培墨兰（Cymbidium sinense （Andr.） Willd.）和蝴蝶兰（Phalaenopsis amabilis Blume）的镰刀菌病害进行了鉴定.经症状观察、病原菌分离培养与回接、病原菌形态观察和内部转录间隔区（Internal transcribed space,ITS）、延伸因子-1α（Elongation factor-1α,EF-1α）序列分析,鉴定出墨兰茎腐病、蝴蝶兰茎基腐病和蝴蝶兰花梗腐烂病等3种镰刀菌病害,其病原菌分别为尖孢镰刀菌（Fusarium oxysporum）、茄镰刀菌（F.solani）和藤仓镰刀菌（F.Fujikuroi）.其中,蝴蝶兰花梗腐烂病（F.fujikuroi）为兰花上首次报道.     

Identification of eight effector candidate genes involved in early aggressiveness of the barley powdery mildew fungus

The barley powdery mildew fungus, Blumeria graminis f. sp. hordei (Bgh), expresses 491 candidate for secreted effector proteins (CSEPs), identified based on presence of a predicted signal peptide and relative sequence uniqueness. Virtually nothing is known about the mechanism of action of CSEPs. The present study used host‐induced gene silencing (HIGS) to identify genes involved in early fungal aggressiveness. Screening of 22 selected CSEP‐encoding genes suggested that CSEP0007, CSEP0025, CSEP0128, CSEP0211, CSEP0247, CSEP0345, CSEP0420 and CSEP0422 are individually required for normal levels of aggressiveness of Bgh. Expression data showed that these genes were up‐regulated at initial stages of infection, suggesting their involvement in early fungal aggressiveness. Altogether, the findings expand the current knowledge of genes contributing to Bgh pathogenesis and provide the basis for future functional characterization.     

甘肃省红豆草病原真菌鉴定及病害发生动态调查

为明确甘肃省红豆草的病害种类、发生动态和危害状况,采用病原物分离与培养、形态学及分子生物学鉴定和致病性测定确定红豆草病害种类,于2012—2013年在通渭、渭源、榆中和碌曲4县调查各病害的发病率以确定发生动态,观察病害田间发生特点并结合调查数据评价其重要性。结果表明,4县共发生真菌性病害12种,分别为大茎点霉叶斑病(病原为大茎点霉属真菌Macrophoma sp.)、壳针孢叶斑病(病原为歪头菜壳针孢Septoria orobina)、炭疽病(病原为白蜡树刺盘孢Colletotrichum spaethianum)、黑秆病(病原为红豆草壳二孢Ascochyta onobrychis、菠菜刺盘孢C.spinaciae和链格孢Alternaria alternata混合侵染)、壳二孢叶斑病、茎点霉叶斑病、尾孢叶斑病、柱格孢白斑病、匍柄霉叶斑病、链格孢黑斑病、锈病和白粉病,其中大茎点霉属真菌、白蜡树刺盘孢和菠菜刺盘孢在红豆草上首次发现;尾孢叶斑病和壳针孢叶斑病为甘肃新记录病害;大茎点霉叶斑病为世界新病害,仅于碌曲县发现。白粉病、锈病、链格孢黑斑病发生于红豆草生长后期,其它病害则始于6月;6—9月危害加重的为黑秆病和柱格孢白斑病,发病率最高达89.7%和96.0%;危害渐轻的为茎点霉叶斑病、壳二孢叶斑病和壳针孢叶斑病,发病率最高达88.7%、57.4%和45.1%。黑秆病和茎点霉叶斑病在甘肃省目前危害最重。     

Pathogenicity,host range and activities of a secondary metabolite and enzyme from Myrothecium roridum on water hyacinth from Thailand

Leaf blight disease of water hyacinth was observed and collected from different geographical areas of Thailand. The disease is caused by a fungal pathogen that was identified as Myrothecium roridum by using its morphological characteristics. The most effective fungal strains were evaluated for pathogenicity on water hyacinth under greenhouse and natural conditions. Myrothecium roridum isolate, Kamphaeng Sean Campus (KKFC) 448, was found to be the most virulent. Different fungal formulations were evaluated for their level of control of water hyacinth. The results showed that spore suspensions with 10% palm oil or 1% Tween 20 caused a higher level of disease severity, compared to spores applied in water alone. The host range of KKFC 448 was evaluated by using 77 plant species that belong to 40 plant families. The fungus did not cause disease on 74 economically important plants but did produce disease signs on water hyacinth and two other aquatic weeds, duckweed and water lettuce. Leaf blight occurs on water hyacinth leaves after being treated with crude extracts of M. roridum and it was indicated that secondary metabolites were released from the fungal mycelia. Myrothecium roridum that was grown on boiled paddy rice produced β‐1,4‐exoglucanase, β‐1,4‐endoglucanase, β‐glucosidase, xylanase and pectinase more than Mroridum that was grown on potato dextrose agar. The results indicated that M. roridum is a pathogen of water hyacinth and the fungus is capable of producing different enzymatic activities on potato dextrose agar and boiled paddy rice, which might be important for infection.     

木塑复合材料耐候性能研究进展

木塑复合材料(WPC)的耐候性能决定了材料的户外使用寿命。文中介绍了国内外在WPC耐热氧老化、耐光氧老化、耐真菌腐朽及耐潮湿与冻融性能方面的研究进展。现有研究表明, 热氧老化与光氧老化均使得WPC发生褪色现象, 力学性能下降, 添加抗氧化剂与光稳定剂可分别改善二者对WPC的破坏作用。WPC中木粉含量较高时更易发生真菌腐朽现象, 添加化学防腐剂或其他助剂、木粉改性及涂饰可有效抑制真菌腐朽。WPC的吸水性是其热氧老化、光氧老化、真菌腐朽及冻融循环过程的催化剂。文中还总结了目前WPC耐候性能研究存在的主要问题, 并对其未来趋势进行了展望。