枯草杆菌PRS5制剂防治柑桔果腐病

应用枯草杆菌Bacillus subtilis PRS 5菌株藕粉制剂,防治由Penicilliumitalicum和P.digitatum引起的收获后柑桔果腐病。23—25℃,30天内对无伤红桔的相对防效达76.9%;25—28℃,70天内对无伤血橙的防效达50%。菌株发酵液浸涂无伤红桔,发病率降低53.8%。     

PRS5对杉苗猝倒病的影响

枯草芽孢杆菌Bacillus subtilis PRS5的不同生物制剂,对杉苗猝倒病Rhizoctonia solani均有明显仿治效果,其中以蛭石麦麸马铃薯葡萄糖固体制剂(VW-PD)4克/公斤土处理最佳,防效为87.37％。     

坚强芽孢杆菌的筛选及抗菌活性

采用三层琼脂法初选对枯斑盘多毛孢P esta lotia funerea有抗生作用的细菌菌株共10株,4株P seudom onas spp.对枯斑盘多毛孢的抗生作用小于6株B acillus spp.;在B acillus spp.中,以B5菌株拮抗带最大,初步鉴定该菌株为芽孢杆菌属的坚强芽孢杆菌B acillus f irm us,对峙培养显示B5对枯斑盘多毛孢有明显的抑菌圈(平均6 mm);B5产生的非挥发性物质对枯斑盘多毛孢菌落的抑制总的表现为稀释度越小,菌落直径生长越小,抑制作用越大,抑制中量为1∶1 000~1∶10 000;B5产生的多糖、粗脂肪、蛋白质对枯斑盘多毛孢孢子萌发有抑制作用,粗脂肪可完全抑制枯斑盘多毛孢的孢子萌发(抑制率为100%),多糖在24 h可完全抑制孢子萌发,蛋白质相对较差,48~72 h抑制率为85%左右.     

绿粘帚霉与坚强芽孢杆菌对松赤枯病的协同生物控制

G.virens与B.firmus对松赤枯病的协同控制显示:(1)预先接种病原菌后(7天)再进行生物防治处理,防治效果在处理间差异不明显,浓度影响无显著差异,即使是两种生防制剂联合使用也未显著提高其防效,但不同树种间的感病性有明显差异;(2)颉抗菌与病原菌同时接种,对松赤枯病有一定防治效果,两菌联合有一定的协同作用,两种菌单独施用防效差异不显著,浓度变化对防效影响不大;(3)预先接种颉抗菌能显著提高防治效果,两种菌联合处理防效更优,感病树种(马尾松、云南松、油松)的感病指数可降至13~15,抗病树种的感病指数可控制在3%左右;在同一浓度下B.firmus与G.virens间无显著差异,在同一颉抗菌下,浓度愈高,防效愈高;(4)三种生防接种方式的平均效果分析表明,G.virens最高平均防效49.5%(黑松),B.firmus为50%(辐射松),两菌联合最高平均防效80%(辐射松);在同一树种条件下,“预先接种颉抗菌”的方式显著高于“颉抗菌与病原菌同时接种”和“预先接种病原菌”,而“颉抗菌与病原菌同时接种”的方式也明显优于“预先接种病原菌”。从防治效果的绝对值来看,“预先接种病原菌”方式在实际生产中表现为病害已发生再进行生防菌处理,这种情况对松赤枯病的控制无实际意义。     

苹果及橙类果实的生物防腐保鲜技术研究

用PRS5菌剂浸涂苹果的防腐保鲜试验表明：低温条件下，“PRS5菌剂 塑膜包装”、“PRS5菌剂 藕粉成膜”及“PRS5菌剂 羧甲基纤维素钠成膜”保鲜效果最优，120天的腐烂率仅为6．7％，相对防效达79．9％，以保鲜膜处理的苹果失水率最低，色泽新鲜。在恒温条件下，以“PRS5菌剂 塑膜包装”和“PRS5菌剂单独处理的效果最佳，120天腐烂率均为13．3％，相对防效达81．9％，但前者果实表面无皱缩，失水率较低。对脐橙而言，PRS5含量越高，防腐效果越好，失水率越低；PRS5菌剂经热处理后，相对防效可下降33．6％；一定时间内，防腐作用随处理时间的延长而增加。在自然条件下，对罗伯森脐橙的相对防腐效果(72天)高达95．15％，与优质化学防腐剂“施保克”效果相当。     

鞍山地区美国白蛾生物防治技术研究

用苏云金杆菌防治美国白蛾,结果显示:不同浓度的药剂对不同虫龄幼虫防治效果有差异,对低龄幼虫防效明显,而对老龄幼虫防效较差。Bt 300～1 000倍液对美国白蛾1～2龄幼虫防效为100%～99.83%,Bt 300～800倍液对3～4龄幼虫防效为99.85%～95.99%,Bt 300～1 200倍液对5～7龄幼虫防效不很理想。采用白蛾周氏啮小蜂防治美国白蛾1代幼虫防效为58.16%,2代幼虫防效为76.54%,而且虫口密度越小,防治的效果越明显,因此认为,释放白蛾周氏啮小蜂防治美国白蛾适合疫情发生较轻的林分。     

杨树内生菌球毛壳抗生物质的培养基优化、检测和动力学

以杨树内生真菌球毛壳ND35为供试菌株,采用L<,16>(4<'5>)正交试验法对液体培养基进行优化;利用pH纸色谱、捷克八溶剂系统纸色谱方法及紫外-可见光谱扫描法对该内生菌的抗生物质进行理化性质初步分析;用薄层层析、高效液相色谱及平板抑菌法检测分析该菌粗提液的活性成分及对杨树腐烂病菌的抑菌效果;对抗生物质液体培养的主要动力学指标进行分析.结果表明:优化后培养基配方为:1%葡萄糖,1%蔗糖,0.5%牛肉膏,0.02%硫酸亚铁,0.01%维生素B<,1>,pH值为7.球毛壳ND35菌株的抑菌作用分为活菌体的抑菌作用和代谢活性物质的抑菌作用,液体培养后的菌丝胞内和胞外均产生抗生物质,并具有较好的热稳定性.该抗生物质pH值为7,易溶于有机溶剂,难溶于水.球毛壳ND35抗生物质在221 nm处有最大的吸收峰,该抗生物质有4个组分,均对杨树腐烂病菌有抑菌活性.生长动力学表明,在液体发酵培养过程中,球毛壳ND35抗生物质的产量、吸光值、pH及其抑菌率是连续变化的.     

杨白潜叶蛾田间药剂防治试验

在河南濮阳选用杀铃脲等4种不同浓度杀虫剂对杨白潜叶蛾幼虫进行了田间药剂防治对比试验,结果显示5%杀铃脲SC、10%吡虫啉WP和48%毒死蜱EC1000倍效果最好,喷药后11 d相对防效均为100%;其次为10%吡虫啉WP、1.8%阿维菌素EC、5%杀铃脲SC和48%毒死蜱EC 1500～2 000倍,相对防效在88%～98%。本着经济、有效、环保的原则,建议生产上在幼虫危害初期用5%杀铃脲SC 1 500～2 000倍树冠喷施或与其它3种杀虫剂2 000倍交替使用进行防治。     

山地橄榄星室木虱防治初报

应用不同药剂、浓度对橄榄星室木虱(Pseudophacopteron canariumYang et Li)进行室内毒力测定和林间防治试验,结果表明:2.5%功夫菊酯乳油对橄榄星室木虱的毒力最高,其相对毒力是苦.烟乳油的1.7倍;复合药剂的防效明显高于单一药剂,最佳组合以功夫乳油5 500倍液+木虱净乳油6 000倍液+苦.烟乳油5 000倍液林间喷雾效果最佳,药后3 d、7 d、14 d、21 d的防效分别为73.63%、90.54%、93.51%、95.43%;连续施用复合药剂7 d的防效达100%,不仅防治效果好,而且持效长,可有效地控制星室木虱的危害。     

四种生物杀菌剂对黄栌枯萎病的防治效果评价

为筛选出防治黄栌Cotinus coggygria枯萎病的高效低毒杀菌剂，选择4种不同生物杀菌剂分别进行盆栽苗防治与田间防治试验。结果表明：枯草芽孢杆菌Bacillus subtilis菌剂和哈茨木霉Trichoderma harzianum菌剂对黄栌枯萎病有一定的防效，并且可以在一定程度上促进植株的生长。盆栽苗中，枯草芽孢杆菌菌剂500倍稀释液防效最好，达到了77.85%；田间防效中，枯草芽孢杆菌菌剂和哈茨木霉菌剂500倍稀释液防效最好，分别为59.15%,55.00%。选择生物杀菌剂防治黄栌枯萎病时，优先选择枯草芽孢杆菌菌剂。     

洋葱伯克霍尔德菌C23抗真菌活性多肽的分离纯化

为了深入研究洋葱伯克霍尔德菌C23(Burkholderia cepacia C23)菌株产生的抗真菌活性物质,以立枯丝核菌(Rhizoctonia solani)为指示菌进行生物活性跟踪,采用有机沉淀法、超滤法、Sephadex G25分子凝胶过滤法对活性物质进行分离纯化。结果表明,洋葱伯克霍尔德菌C23菌株产生的抗真菌活性物质为分子量5 000～10 000 Da的多肽类物质;建立了用超滤、分子凝胶过滤快速有效分离纯化伯克霍尔德菌C23菌株活性多肽的技术方法,为进一步制备单一的活性多肽成分奠定了基础。     

诱导和非诱导条件下喙尾琵甲幼虫抗菌肽分离及抑菌活性比较

对混合菌液诱导和非诱导处理的喙尾琵甲幼虫抗菌肽进行了分离纯化及抑菌活性比较。结果显示:诱导组和非诱导组粗提物无抑菌活性,但是经凝胶色谱分离后,从非诱导组获得组分DZP1,对金黄色葡萄球菌、枯草芽孢杆菌表现出抑制作用;从诱导组获得组分YDP1,对金黄色葡萄球菌、枯草芽孢杆菌、绿脓杆菌具有活性,且YDP1活性明显强于DZP1;Tricine-SDS-PAGE检测表明DZP1和YDP1组成、种类基本一致,主要由20 kD以下分子量的小肽组成。研究结果表明:喙尾琵甲幼虫在诱导和非诱导条件下均可分离到具有抑菌活性的抗菌肽,菌液诱导可增强抗菌肽的活性和抑菌谱。     

A new polysaccharide from leaf of Ginkgo biloba L

A water-soluble polysaccharide, GPB, was obtained from leaf of Ginkgo biloba L by hot water extraction followed by precipitation with ethanol and fractionation with gel chromatography. The results of HPLC with TSK-GEL column and gel filtration chromatography with Sepharose CL-6B analysis indicated GPB was uniform in polarity and its molecular weight (MW) was about 10 kDa. The structure of GPB was analysed using chemical methods, IR spectroscopy, and NMR spectroscopy. GPB has a high branched structure with polygalactose as core part of backbone. The repeating unit of polygalactose consists of 1,6-linked Galactose (Gal) and 1,3,6-linked Gal.     

杨树烂皮病菌颉颃菌株的初步筛选与分子鉴定

对杨树烂皮病菌的平板对峙试验结果表明,6种颉颃真菌中木霉的抑菌率最高为51%,而颉颃细菌4个菌株的抑菌率均在60%左右,说明颉颃细菌的抑菌效果明显高于颉颃真菌;对B137等4株颉颃细菌的分子鉴定认为,1株为枯草芽孢杆菌(Bacillus subtilis),2株为解淀粉芽孢杆菌(Bacillus amyloliquefaciens),还有1株为苏云金杆菌(Bacillus thuringiensis,Bt);解淀粉芽孢杆菌和苏云金杆菌对杨树烂皮病菌有较好的颉颃效果。     

捏合温度和木纤维水分对木纤维-聚乳酸复合材料中聚乳酸的影响

采用捏合法制备木纤维-聚乳酸(WF-PLA)复合材料。通过凝胶色谱法(GPC)和差示扫描量热法(DSC)研究捏合温度和木纤维水分对WF-PLA生物质复合材料中聚乳酸分子质量及热性能的影响。结果表明:捏合温度对WF-PLA生物质复合材料中PLA性能影响显著。随着捏合温度由180℃升高到200℃,WF-PLA复合材料中PLA的重均分子质量(M珚w)明显下降,数均分子质量(M珚n)在200℃时也明显下降,在190℃时,PLA分子多分散系数最小。不同捏合温度的WF-PLA复合材料中,PLA熔融温度略有不同,熔融温度变化与PLA分子质量相关。木纤维水分对捏合法制备的WF-PLA复合材料中PLA的分子质量和热性能的影响不显著。     

Delignification of cell walls of <Emphasis Type="Italic">Chamaecyparis obtusa</Emphasis> during alkaline nitrobenzene oxidation

To clarify the behavior of whole lignins in wood cell walls during alkaline nitrobenzene oxidation, the delignification process from cell walls in normal and compression woods of Chamaecyparis obtusa Endl. (Cupressaceae) was observed using ultraviolet and transmission electron microscopies. The lignin content conspicuously decreased to around 10% after 35min in normal wood. The lignin content in compression wood finally leveled off at aroumd 10% after 50min. In gel filtration of oxidation products in ethyl acetate, a high molecular weight fraction was prominent in extracts from the early stage of the reaction. As the oxidation progressed, the high molecular weight fraction became less prominent in both normal and compression wood. Changes in the weights of cell wall residues during reaction indicated that approximately half of the components other than lignin were also removed from the cell walls. This shows that the majority of lignin with relatively high molecular weight is removed from the cell walls together with polysaccharides in the early stage of the reaction and that further oxidative degradation occurs in solution in later stages. Only a small amount of the lignin with low molecular weight could be analyzed by gas chromatography.Parts of this report were presented at the 47th (Kochi, April 1997) and 48th (Shizuoka, April 1998) Annual Meetings of the Japan Wood Research Society, and at the Lignin Symposium, Sapporo, October 1997     

Decolorization of kraft pulp bleaching effluent by a newly isolated fungus, Geotrichum candidum Dec 1

Kraft pulp bleaching effluent supplemented with glucose was decolorized by a newly isolated fungusGeotrichum candidum Dec 1 (Dec 1) that showed a wide decolorizing spectrum to synthetic dyes. When the glucose concentration in the effluent was 30 g/l, the color removal and the reduction of absorbable organic halogens were 78% and 43% after 7 days culture, respectively. The average molecular weight of colored substances measured by gel filtration chromatography was lowered to less than 3000 from 5600 after 7 days culture. As the contribution of extracellular enzymes such as peroxidase (DyP), manganese peroxidase, and laccase to the decolorization of the kraft pulp bleaching effluent was small, Dec 1 appears to have a different mechanism of decolorizing kraft pulp bleaching effluent when compared with enzymes used to decolorize synthetic dyes.     

杨树重要病害生物防治初探

自然界各种微生物生活在一起,成为复杂的群落。它们相互促进、制约,构成生物体的生态平衡。在森林病害防治中,利用益菌控制病菌的生存和活动,达到生物防治的目的。为了寻求这一新途径,在1982—1984年,对4种杨树重要病害进行了生物防治探索,从筛选和防病上作了研究。     

Preparation and Characterization of the Phenolated Wood Using Sulfuric Acid as a Catalyst Ⅱ. FT-IR and GPC Characterization

By means of gel permeation chromatography analysis, the molecular weight of liquefied wood under different reaction conditions was investigated to trace the change in the structural characteristics of the liquefied wood. The insoluble residues were analyzed by Fourier transform infrared to investigate the liquefaction order of three main wood components. The results indicate that both reaction temperature and reaction time could affect the molecular characteristics of the liquefied wood obtained. The molecular weight of liquefied Chinese Fir wood is higher than that of liquefied Poplar wood under most of reaction conditions. During wood liquefaction, lignin is liquefied firstly. Hemicellulose is liquefied in the middle stage and cellulose is the most difficult to be liquefied.     

Antibacterial activity of seed proteins of Robinia pseudoacacia

A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed.