壳聚糖控制工厂化蔬菜病害的研究

应用壳聚糖对7种工厂化蔬菜病害的研究结果表明：壳聚糖对工厂化蔬菜病害有较好的控制作用，效果可达60％－80％，一般叶部病害的施药浓度以500倍液为宜，施药次数应为3次，对根部病害以灌根处理为好，一般用药量300ml左右.     

异菌脲对桃树褐腐病防效和膳食风险评估

褐腐病是桃树主要病害之一,发生较重时可降低桃树产量和品质,威胁桃产业发展。本研究开展了异菌脲对桃树褐腐病1年3地的田间药效试验和1年8地的农药残留试验,进行了膳食风险评估。试验结果表明,50%异菌脲WP能有效防治桃树褐腐病,防效最高可达85.53%;药后7～12 d,药剂在果肉中残留量为0.046～3.920 mg/kg,小于最大残留限量10 mg/kg;RQ为26.5%,膳食风险可接受。推荐50%异菌脲WP使用有效剂量为333.3～500 mg/kg（制剂量1 000～1 500倍液）,于桃树谢花后开始施药,间隔7～14 d施药1次,连续施药3次,安全间隔期为7 d。     

70%甲硫·三环唑可湿性粉剂对水稻稻瘟病及后期病害综合防治效果

[目的]筛选安全高效防治水稻稻瘟病及后期病害的杀菌剂。[方法]连续3年开展70%甲硫·三环唑可湿性粉剂田间药效试验。[结果]70%甲硫·三环唑可湿性粉剂防治水稻稻瘟病,轻发区用量315 g a.i./hm2,重发区用量525 g a.i./hm2,防效78.3%~80.7%;孕穗期第1次施药,间隔7 d施第2次或仅在破口期施药1次,防效无明显差异;兼治纹枯病防效75%左右,对水稻后期病害防效78%。[结论]70%甲硫·三环唑可湿性粉剂对水稻稻瘟病及后期病害具有良好防效。     

50%丙环唑·左旋松油醇乳油防治香蕉叶斑病田间药效试验

2007~2008年的田间试验表明,50%丙环唑.左旋松油醇乳油可有效防治香蕉叶斑病,而且对香蕉安全。在稀释600~2000倍条件下,施药3次后该乳油对香蕉叶斑病防效为62.23%~77.27%。其中稀释1000倍液的防效为66.93%~74.52%,优于同等稀释倍数的25%丙环唑乳油,说明丙环唑和左旋松油复配可以提高防效。     

20%噻森铜悬浮剂防治水稻白叶枯病田间试验

介绍了20%噻森铜悬浮剂对水稻白叶枯病的田间防效。田间试验表明,20%噻森铜悬浮剂对水稻白叶枯病具有良好的防效。在发病初期,使用20%噻森铜悬浮剂300～500倍液,连续用药3次,防效可达约80%。20%噻森铜悬浮剂是防治水稻白叶枯菌的良好药剂。     

50%丙环唑·左旋松油醇乳油防治香蕉叶斑病田间药效试验

2007~2008年的田间试验表明,50%丙环唑.左旋松油醇乳油可有效防治香蕉叶斑病,而且对香蕉安全。在稀释600~2000倍条件下,施药3次后该乳油对香蕉叶斑病防效为62.23%~77.27%。其中稀释1000倍液的防效为66.93%~74.52%,优于同等稀释倍数的25%丙环唑乳油,说明丙环唑和左旋松油复配可以提高防效。     

苏云金芽孢杆菌防治小菜蛾的田间试验

应用苏云金芽孢杆菌防治小菜蛾的田间药效试验结果表明:苏云金芽孢杆菌500倍对小菜蛾具有良好防效,施药后3d的防效达73.6%,药后5d的防效达85.5%。     

高效低毒矿物源农药“绿颖”防治黄瓜白粉病试验

白粉病是瓜类蔬菜普遍发生且为害严重的病害之一，试验结果表明绿颖200、300倍施用对黄瓜白粉病都有很好的防治效果，对黄瓜安全并有促进生长的作用，生产上使用绿颖防治黄瓜白粉病以200～300倍稀释液为宜，在发病前或发病初期进行喷雾防治，隔8天施药一次，施药2～3次可以达到比较好的防效。     

75％百菌清WG防治番茄晚疫病田间药效试验

研究了75％百菌清WG对番茄晚疫病的防治效果。结果表明：75％百菌清WG对番茄晚疫病的防治效果较好，第三次施药后14d对番茄晚疫病叶部病害的防效可达73．19％～78．36％，且显著减少病果率，对番茄早期产量的增产率为16．49％～22．17％。     

10%苯醚菌酯悬浮剂防治葡萄霜霉病田间药效试验

进行了10%苯醚菌酯悬浮剂防治葡萄霜霉病田间药效试验。结果表明,10%苯醚菌酯悬浮剂是防治葡萄霜霉病的较好药剂,其防效较高,在葡萄霜霉病发病初期施药,可有效控制病害的发生蔓延,并有一定的持效性。在试验剂量范围内对葡萄安全。建议施用剂量为10%苯醚菌酯悬浮剂500～1000倍液(100～200 mg/L),在发病初期施药。     

Antifungal Activity of Leaf Essential Oil and Extracts of <Emphasis Type="Italic">Metasequoia glyptostroboides</Emphasis> Miki ex Hu

Plant diseases constitute an emerging threat to global food security. Many of the currently available antifungal agents for agriculture are highly toxic and nonbiodegradable and cause extensive environmental pollution. Moreover, an increasing number of phytopathogens are developing resistance to them. Therefore, the aim of this study was to assess the antifungal efficacy of the leaf essential oil and the leaf extracts of Metasequoia glyptostroboides against Fusarium oxysporum, Fusarium solani, Phytophthora capsici, Colletotrichum capsici, Sclerotinia sclerotiorum, Botrytis cinerea and Rhizoctonia solani. The oil (1,000 μg/disc) and the extracts (1,500 μg/disc) revealed a remarkable antifungal effect against the tested plant pathogenic fungi with a radial growth inhibition percentage of 41.3–66.3% and 13.4–54.4%, respectively along with their respective MIC values ranging from 62.5 to 1,000 μg/ml and 500–4,000 μg/ml. The oil had a strong detrimental effect on spore germination of all the tested plant pathogens along with the concentration as well as time-dependent kinetic inhibition of Botrytis cinerea. Also, the oil exhibited a potent in vivo antifungal effect against Phytophthora capsici on greenhouse grown pepper plants. The results of this study indicate that the oil and extracts of M. glyptostroboides leaves could become natural alternatives to synthetic fungicides to control certain important plant fungal diseases.     

常用杀菌剂生物测定中稀释母液的配制方法

介绍了杀菌剂生物测定中常用杀菌剂稀释母液的配制方法。对于杀菌剂原油及易溶于环己酮的固体原药可配制成1%的水乳剂或微乳剂母液,溶剂用量为0～2.5%,加入1%的正丁醇增加体系的稳定性,表面活性剂选用1602#和AEO–6(质量比3﹕1),质量分数2%。易溶于水的原药可配制成1%水剂,加入1%的1602#,以增加湿润展布性能。对于选择溶剂困难的固体原药可配制成1%水悬浮剂母液,其中润湿分散剂为2%1602#和1%农乳500#,粘度调节剂为0.2%黄原胶。上述母液体系组成简单,减少了有机溶剂、表面活性剂等对毒力测定结果的干扰,便于提高生物测定结果的可靠性和可比性。     

Optimization and Evaluation of a Chitosan/Hydroxypropyl Methylcellulose Hydrogel Containing Toluidine Blue O for Antimicrobial Photodynamic Inactivation

Photodynamic inactivation (PDI) combined with chitosan has been shown as a promising antimicrobial approach. The purpose of this study was to develop a chitosan hydrogel containing hydroxypropyl methylcellulose (HPMC), chitosan and toluidine blue O (TBO) to improve the bactericidal efficacy for topical application in clinics. The PDI efficacy of hydrogel was examined in vitro against the biofilms of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa). Confocal scanning laser microscopy (CSLM) was performed to investigate the penetration level of TBO into viable S. aureus biofilms. Incorporation of HMPC could increase the physicochemical properties of chitosan hydrogel including the hardness, viscosity as well as bioadhesion; however, higher HMPC concentration also resulted in reduced antimicrobial effect. CSLM analysis further demonstrated that higher HPMC concentration constrained TBO diffusion into the biofilm. The incubation of biofilm and hydrogel was further performed at an angle of 90 degrees. After light irradiation, compared to the mixture of TBO and chitosan, the hydrogel treated sample showed increased PDI efficacy indicated that incorporation of HPMC did improve antimicrobial effect. Finally, the bactericidal efficacy could be significantly augmented by prolonged retention of hydrogel in the biofilm as well as in the animal model of rat skin burn wounds after light irradiation.     

壳聚糖与柠檬醛缩合反应产席夫碱及其抗菌活性

通过壳聚糖与柠檬醛在超声波振荡下反应制备了壳聚糖缩柠檬醛席夫碱。采用[L9（33）]正交实验探讨了反应时间、反应温度及反应物配比对壳聚糖席夫碱缩合率和取代度的影响。最佳条件为：反应物配比n（壳聚糖）∶n（柠檬醛）=1∶6,反应温度40～50 ℃,反应时间10 h,壳聚糖席夫碱的缩合率可达86%,取代度为0.82。红外光谱和X射线衍射光谱结果表明产物具有壳聚糖席夫碱的结构特征。对大肠杆菌、金黄色葡萄球菌和黑曲霉的抗菌实验表明,该产物对大肠杆菌、金黄色葡萄球菌和黑曲霉的最低抑菌浓度分别为1 g/L、1 g/L和5 g/L,其抗菌活性随浓度的增加而增加,且优于壳聚糖。     

蛇床子素结构修饰物JS-B对辣椒疫霉生物活性

对蛇床子素结构修饰物JS-B的生物活性进行了研究.室内生测结果表明:JS-B对辣椒疫霉菌丝干重和游动孢子萌发的抑制中浓度(EC50)分别为43.74、86.03 mg/L.盆栽试验表明:JS-B处理对辣椒疫病有一定预防和治疗效果.根系对JS-B具有一定的吸收性,1000 mg/L JS-B灌根处理,防效达67.16%.用400 mg/L的JS-B喷雾处理辣椒幼苗,分别在施药后1、3、8 d接种辣椒疫霉的游动孢子,其对辣椒疫病的防效分别为71.95%、61.90%和66.72%,与阳性对照药剂烯酰吗啉相当,说明JS-B在防治辣椒疫病中具有一定的持效期.     

对氨基苯甲酸乙酯的合成新方法

以高脱乙酰度的壳聚糖为原料,制备了酯化催化剂壳聚糖硫酸盐。以对氨基苯甲酸、无水乙醇为原料,在壳聚糖硫酸盐的催化下,通过微波辐射加热,合成出对氨基苯甲酸乙酯。讨论了催化剂用量、反应时间、微波辐射功率等条件,结果表明,微波辐射功率为300 W,对氨基苯甲酸0.01 mol,酸醇物质的比为1∶15,催化剂用量0.5 g,反应10 min时,反应条件最佳,收率达83.6%。     

明胶与壳聚糖复凝聚过程的研究

本文研究了四种明胶与两种壳聚糖组成的体系的复凝聚过程,对于复凝聚过程的主要影响参数(pH值、配比和盐类)与体系复凝聚产率的关系进行了探讨。发现选用二价金属盐类对体系复凝聚产率的影响明显不同于一价金属盐类,少量CaCl_2(≯0.30％)的加入可提高复凝聚产率;具有高冻力的RT-52354和RT-53808两种明胶较适用于进行复凝聚;采用分子量大、脱乙酰度较低(-NH_2含量较少)的壳聚糖有利于提高复凝聚产率;并且对上述两种明胶与壳聚糖体系确定了比较适宜的复凝聚条件。     

Functional hybrid fibers of cellulose/microcrystalline chitosan. I. Manufacture of viscose/microcrystalline chitosan fibers

Blends of microcrystalline chitosan (MCCh) with cellulose xhanthate alkaline solutions were prepared to investigate the effects of aqueous MCCh gel concentration and additives on the spinnability of hybrid cellulose/chitosan fibers and their properties. The properties of the spinning solution were mainly dependent on the concentration of MCCh in the aqueous gel‐like dispersion and the amount mixed into the cellulose xhanthate solution. Sodium alginate chemically close to cellulose and chitosan was used as an additive to improve the miscibility of chitosan due to the ionic bonds formed with chitosan 2‐amino groups. Using an optimized ratio of 2 : 1 of MCCh to the sodium alginate, a maximum of 6% of MCCh calculated from alpha‐cellulose content could be introduced into the sodium xhanthate solution containing originally 9% of alpha‐cellulose. The yield of MCCh in the resulting fibers was dependent on the molecular mass, and varied between 73–82%. The strength, elongation, and color of the resulting hybrid fibers were only slightly changed and the WRV remarkably increased compared to standard fibers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1725–1730, 2000     

谷胱甘肽和壳聚糖美白活性的研究

通过测定壳聚糖、壳低聚糖、谷胱甘肽对酪氨酸酶活性的抑制率，对它们的美白功效进行了测定，并与熊果苷进行了比较。结果表明，壳聚糖、壳低聚糖、谷胱甘肽对酪氨酸酶活性有明显的抑制作用，其中谷胱甘肽的抑制作用最为明显，在较低的浓度下就具有很高的抑制效果；把壳聚糖和谷胱甘肽与熊果苷复配，可使抑制率达到90％以上。     

腐植酸液肥（L-CHA）在小麦上施用的增产效应研究

考察了腐植酸液肥（L—CHA）在小麦上施用的增产效应。结果表明,与对照相比．施用L-OHA液肥处理的小麦可增产12．6％～15．4％．稀释1000倍、2000倍、4000倍的不同处理间无明显差异。