Effects of two kinds of boron-based fungicides on the properties of Bambusa emeiensis bamboo scrimber.

以慈竹为原料,酚醛树脂（PF）为胶黏剂,硼酸锌（ZB）、硼硼合剂（SBX）为防霉剂,五氯酚钠（Na—PCP）为对照药剂制备慈竹重组材,研究添加ZB和SBX对重组竹的物理力学性能及防霉性能的影响。结果表明：ZB和SBX对蓝变菌的防治效力很差。ZB和SBX的添加会削弱板材的物理力学性能,但防霉性能显著提高。研究范围内,这2种药剂的防霉变合理使用量分别为0．70％（ZB）和0．49％（SBX）。     

中华猕猴桃褐斑病病原鉴定及抑菌药剂筛选

【目的】确定引起中华猕猴桃褐斑病病原菌种类,研究常用杀菌剂对该病原菌菌丝生长的抑制作用。【方法】对病原菌进行分离、纯化、致病性测定以及形态学、分子生物学鉴定,确定病原菌种类;选用常用的18种杀菌剂分别对病原菌进行抑菌效果测定,并建立毒力回归方程;筛选出有效的抑菌药剂,为防治该病的发生提供理论依据。【结果】从不同病斑上分离出了3个纯化菌株,其形态特征相同。通过病原菌rDNA-ITS克隆测序、比对分析,3个菌株为同一致病菌,应用BLASTn比对结合形态学特征确定该致病菌为链格孢（Alternaria alternata (Fr.:Fr.) Keissler）。在10 μg•mL-1含药PDA平板上,7种杀菌剂对链格孢菌菌株的抑菌率均大于80%,分别为400 g•L-1氟硅唑、500 g•L-1异菌脲、80%戊唑醇、10%多抗霉素B、12.5%烯唑醇、33.5%喹啉酮和10%苯醚甲环唑。【结论】确定中华猕猴桃褐斑病由链格孢引起,400 g•L-1氟硅唑、500 g•L-1异菌脲、10%多抗霉素B和10%苯醚甲环唑对链格孢抑菌效果较强。     

15种中药提取物对几种植物病原菌抑菌活性的初步研究

以15种中药丙酮提取物为材料,测定了其对杨树溃疡病菌(D.gregaria)、棉花枯萎病菌(F.oxys-porum f.sp.vasinfectum)、番茄早疫病菌(A.solani)、小麦纹枯病菌(R.solani)和小麦赤霉病菌(F.graminearum)等5种植物病原菌的生物活性。结果表明,在质量浓度为0.05 g/mL时,花椒提取物对所有供试菌菌丝生长抑制率均在80%以上,苍术、沉香、艾叶和草豆蔻提取物对其中至少2种供试菌菌丝生长抑制率均在60%以上;在质量浓度为0.1 g/mL时,花椒、沉香和艾叶提取物对棉花枯萎病菌孢子萌发抑制率均在90%以上;草豆蔻提取物对棉花枯萎病菌孢子萌发抑制率大于65%。花椒、沉香、艾叶、草豆蔻、苍术等5种中药作为植物源杀菌剂值得进一步研究。     

不同药剂对草毛虫的防治效果研究

[目的]选择防治有机茶园茶毛虫的有效药剂.[方法]选择3种生物农药和1种化学农药进行荼毛虫防治效果筛选试验.[结果]化学农药10％联苯菊酯乳油对茶毛虫的防治效果最好,见效最快;生物农药16 000 IU/mg苏云金杆菌可湿性粉剂和0.3％苦参碱水剂对茶毛虫也具有较好的防治效果;0.3％印楝素乳油的防治效果相对较差.[结论]建议在有机茶生产中使用生物农药防治茶毛虫,采取几种药剂交替轮换使用.     

An inhibitor of polyamine biosynthesis — Difluoromethylornithine — and the polyamine spermidine for the control of gray mold(Botrytis Cinerea)

Difluoromethylornithine (DFMO) — an inhibitor of polyamine biosynthesis, and the polyamine spermidine (Spd) reduced gray mold of tomato, pepper, eggplant, bean andSenecio sp. leaves, and of rose petals by 37–88% when applied at 0.1–1.0 mM each. Higher doses did not result in better control. The disease was also reduced significantly on tomato fruits by 1.0 inM DFMO and by 0.1–1.0 mM Spd, and on cucumber fruits by 0.1–1.0 mM of both compounds, but not on grape berries. The combination of 0.2 mM DFMO with 1.0 mM Spd controlled gray mold ofSenecio sp. and tomato leaves additively better than either treatment alone, whereas this effect was not observed in leaves of lettuce and pepper. Ethylene production was reduced significantly by Spd applied to leaves of tomato and pepper, but not by DFMO. Linear growth and germination of the fungus were affected by lower concentrations of DFMO (ED50 0.12–0.97 and 1.4, respectively) as compared with Spd. Spermidine and DFMO controlled white mold(Sclerotinia sclerotiorum) as effectively as did the fungicide benomyl. Contribution from the Agricultural Research Organization. No. 3195-E, 1991 series.     

不同杀菌剂对草坪草病原菌毒力的作用测定

采用生长速率法测定了不同杀菌剂对3种主要引起坪草病害的褐斑病菌、腐霉枯萎菌、夏季斑枯病菌的毒力。结果表明,烯唑醇、甲基硫菌灵、代森锰锌、咪鲜胺对立枯丝核菌的EC50值分别为0.078 3,5.968 4,7.181 2和11.386 8 mg/L,以烯唑醇对立枯丝核菌的毒力最高。烯唑醇、咪鲜胺、代森锰锌、甲基硫菌灵对夏季斑枯病菌的EC50值分别为0.016 2,0.554 4,6.035 3,1 218.497 8 mg/L,以烯唑醇抑菌效果显著优于其它3种杀菌剂。采用菌丝干重测定法测定了阿米西达、霜脲氰、霜克、咪鲜胺、代森锰锌对腐霉枯萎病菌的毒力,其EC50值依次为0.053 3,7.837 4,13.310 7,19.715 1,29.771 5 mg/L,以阿米西达的抑菌效果最好。     

西藏八角莲炭疽病病原鉴定及室内药剂筛选

从西藏大学农牧学院药材基地的西藏八角莲叶片病斑上分离到1种炭疽病菌,根据病害症状特点、病原菌形态特征、培养性状和致病性测定等进行鉴定,结果表明:西藏八角莲炭疽病的病原菌为半知菌亚门,腔孢纲,黑盘孢目,刺盘孢属(Colletotrichum sp.)。药剂筛选试验结果表明,对菌丝生长和孢子萌发均有强烈抑制作用的药剂有80%福.福锌可湿性粉剂、58%甲霜灵可湿性粉剂、50%多菌灵可湿性粉剂、72%霜脲.锰锌可湿性粉剂,稀释倍数在2000倍时,对菌丝和孢子的抑制率均达90%以上。     

Occurrence in Italy and characteristics of lettuce downy mildew (Bremia lactucae) resistant to phenylamide fungicides

Control of lettuce downy mildew (Bremia lactucae) with phenylamide fungicides has failed in some intensive lettuce-producing areas in Northern Italy since Spring 1993. Before then, these chemicals and particularly metalaxyl, provided the best disease control. The sensitivity of Bremia lactucae isolates collected in such areas to metalaxyl was evaluated in the laboratory. These strains grew and sporulated profusely on lettuce seedlings treated with 100 and 200 ppm of metalaxyl, whereas sensitive control strains were completely inhibited when treated with fungicide concentrations ranging from 0.5–1 ppm. Thus in Italy occurrence of resistance to phenylamide fungicides in Bremia lactucae has also been demonstrated, as in almost all the countries where these chemicals were previously authorised. Subsequently, a demonstration of occurrence of resistance was made and the virulence pattern of several strains (resistant and sensitive to metalaxyl) was characterised using differential NL series containing the 13 DM resistant genes or R factors. The results suggest the occurrence of a new pathotype in Italy different from all the 16 NL Bremia lactucae races studied.     

胡椒瘟病病原菌对12种杀菌剂的敏感性测定

采用生长速率法测定了胡椒瘟病病原菌对常用的12种杀菌剂的敏感性。试验结果表明，胡椒瘟病病原菌对不同供试杀菌剂的敏感性存在明显差异，其中69　%烯酰吗啉·锰锌WP、25　%甲霜·霜霉WP、50 %烯酰吗啉WP和36 %霜休锰锌WP对病原菌的抑菌效果好且敏感性高，EC50分别为1.862　1、1.129 8、3.419 8和6.309 6　μg/mL；50 %琥铜甲霜WP次之。     

几种杀菌剂对南方红豆杉炭疽病的田间药效测定

在田间药效测定中,喷雾和注干两种施药方法相比,喷雾防治的效果明显好于注干的防治效果。喷雾试验中,防治效果最好的是甲基托布津,平均防治效果达到78.79%,最差的是退菌特,平均防治效果为57.20%;在注干防治试验中,防治效果最好的依然为甲基托布津,为62.50%,其次为炭克、多菌灵,最差的为退菌特,为46.57%。