不同真菌菌剂对烟草病毒病的田间防治效果

真菌激发子能诱导植物产生系统抗性,表现出抗植物病毒的作用。对西瓜枯萎菌、苹果轮纹菌、小麦赤霉,以及土壤真菌ESF-6菌株、XFPF-6菌株、C1菌株、XFSF-8菌株、疫霉等8种真菌菌剂的抗病毒活性进行了研究。用不同真菌发酵液喷雾处理田间烟草植株叶片,检测真菌菌剂对烟草病毒病的防治效果。结果表明,8种真菌菌剂对烟草病毒病均有一定的防治效果,其中ESF-6菌剂防效最高,发病高峰期的防效为83.8%。在烟草整个生长期真菌XFPF-6的防效较为稳定,防效稳定在60%以上。小麦赤霉菌,苹果轮纹菌的防效也较高,分别为64.8%,73.7%。除C1菌剂外,其他7种真菌菌剂的防效均高于盐酸吗啉胍,可开发为真菌抗病毒菌剂。经18s rRNA序列测定和显微形态观察鉴定ESF-6为曲霉(Aspergillus sp.),XFSF-8为青霉(Penicillium sp.)。     

烟草灰霉病侵染条件的研究

烟草灰霉病是黑龙江烟区新发现病害，个别地块已造成严重损失。自１９９０～１９９５年利用田间试验和控制条件接种方法，研究了烟草灰霉病病菌侵染来源和侵染规律，试验发现：①灰霉病菌Ｂｏｔｒｙｔｉｓｃｉｎｅｒｅａ侵染烟株的最适宜温度在１８℃左右，９℃以下或２７℃以上不能发生侵染，该菌发生侵染还必须满足９ｈ以上的湿润时间，１２～２４ｈ持续湿润利于侵染，光照对病菌侵染有抑制作用。②病菌的侵染来源主要是来自烟株病残体产生的分生孢子。③黑龙江烟区有两个侵染高峰，一个在６月中、下旬，另一个在８月中、下旬。这期间低温、多雨侵染率较高。     

香菇多糖的研究进展

香菇多糖作为香菇中重要的药用活性成分 ,其国内外研究概况、免疫药理作用、提取分离纯化步骤及其纯度、含量测定和结构鉴定分析方法等在本文中作了详细介绍。     

香菇多糖生物活性研究进展

香菇多糖(lentinan，LNT)是从伞菌科真菌香菇(lentinusedodes)的子实体中分离到的一种β-1，3葡聚糖，本文综述了香菇多糖的免疫调节活性、抗感染和抗肿瘤等生物活性及其研究前沿。     

灵芝多糖和香菇多糖保健食品的研究

<正> 随着人民生活水平的提高和平均寿命的延长,人口老龄化已经成为人们日益关注的社会问题。当人进入老年期以后,体质、免疫系统功能和对疾病感染的抵抗力逐渐衰退,容易引起各种疾病。通过一系列的研究证实了灵芝和香菇等含有的高分子多糖,具有增强和调节免疫功能、提高对疾病感染的抵抗力和延缓衰老等生理活性。     

香菇多糖抑菌作用初探

对干香菇及鲜香菇分别采用三氯乙酸法提取获得干香菇粗多糖提取物和鲜香菇粗多糖提取物,对两种提取物的抑菌作用进行比较,并对两种香菇多糖抑菌作用的热稳定性进行了考察。结果表明,干、鲜香菇粗多糖提取效果分别为11.79mg/g和5.37mg/g香菇干物质重。2种提取物均对3种酵母菌(saccharomgces cerevislae、Saccharomyces fruit、Saccharomycesellipsoideus)和2种细菌(Bacillus subtilis、Escheirchia coli)有一定的抑制作用,但是对粉红单端孢和青霉无抑菌作用。不同温度的热处理对两种香菇多糖的抑菌作用没有影响。     

氮气对储烟害虫烟草甲的防治效果

为明确实验室及实仓条件下,氮气对储烟害虫烟草甲4种虫态（幼虫、蛹、成虫、卵）的防治效果,在实验室设置20、25、30℃三个温度,以95%和99%浓度的氮气处理4种虫态的烟草甲,分别在1、2、4、6、8、10、12、14 d后取出,记录试虫死亡情况;在烟仓自然条件下,以99%浓度的氮气处理密闭烟垛中的烟草甲,分别在第9天和第30天取出,记录试虫死亡情况。结果表明,实验室条件下,6个组合处理对各虫态烟草甲均有一定的致死作用,且致死效果随氮气浓度的升高、温度的升高和处理时间的延长而增强。同时,氮气处理对不同虫态烟草甲的防治效果差异显著,对卵和成虫的防治效果高于其他虫态。99%浓度氮气在20、25、30℃条件下处理烟草甲卵4 d,99%浓度氮气在30℃条件下处理烟草甲成虫4 d,校正死亡率即可达100%;实仓条件下,99%浓度氮气处理密闭烟垛9 d,对烟草甲幼虫、蛹、成虫的校正死亡率可达100%。因此,20~30℃条件下,运用氮气杀虫技术可有效防治烟仓中各虫态烟草甲,温度越高、氮气浓度越大效果越好。     

香菇多糖脱色方法的研究

从香菇菌丝体中提取的香菇多糖色素含量较高,实验采用活性炭对香菇多糖进行脱色,探讨了活性炭用量、吸附时间、pH值、脱色温度对脱色的影响,确定了脱色的最佳工艺。     

超高压提取香菇多糖的研究

对超高压提取香菇多糖的工艺进行探讨。以多糖得率为评价指标,考察压力、温度及保压时间对香菇多糖提取率的影响。通过单因素试验和正交试验确定最佳工艺条件为:在保压时间4.0min时,压力350MPa,固液比1:35,温度55℃,此条件下做验证实验,香菇多糖得率为8.96%,是水浸提的2.23倍,比超声波酶解法提取率高出48.83%。超高压提取具有得率高,提取温度低、提取时间短、节能等优点,为香菇多糖的提取提供了一种新技术。     

香菇多糖的提取数学模型研究

运用统计分析方法,采用五元二次回归正交旋转组合设计进行香菇多糖提取试验,选择酸的浓度(mol/L)x1、料液比x2、浸提时间(t)x3、浸提温度(℃)x4、加醇比x5为调控因子,以香菇多糖的提取率y为目标函数,建立数学模型,经微机仿真寻优,决策出对香菇多糖提取有影响的5个因素的最佳范围是酸的浓度0.16￣0.23mol/L、料液比1∶36～1∶49、浸提时间2.7￣3.8h、浸提温度50￣67.8℃、加醇比1∶2￣1∶3组合方案,并研究了各项措施的交互作用效应,为香菇多糖的提取提供科学依据。     

烟草灰霉病病原鉴定及其生物学特性

对广西烟草灰霉病的病原、生物学特性进行了初步的研究.根据该病原菌的形态特征、致病性及rDNA-ITS序列测定,将该病原菌鉴定为灰葡萄孢(Botrytis cinerea Pers).该病原菌菌丝在5℃-30℃的温度范围内均可生长,产生分生孢子的温度范围为10℃-25℃,菌核形成温度范围为15℃-22.5℃,最适温度均为20℃;分生孢子萌发的温度范围为7.5℃-30℃,最适温度为20℃-25℃.在pH2-9的范围内该菌均能生长,最适pH为6.分生孢子需在高湿条件下才能萌发,相对湿度低于100％时不能萌发.完全光照对该菌菌丝生长有促进作用,而完全黑暗更利于产孢、孢子萌发及菌核的形成.单糖及双糖、有机氮及硝态氮足病原菌较好的C、N源.分生孢子和菌核的致死温度分别是42℃和46℃.     

Control strategies against grey mould (Botrytis cinerea Pers.: Fr) and corresponding fungicide residues in grapes and wines

This study examines the most effective anti-Botrytis strategies leading to possible lower pesticides residues in wine. To provide wine growers with a number of high-quality solutions for protection against Botrytis for their vineyards while minimizing pesticide residues in the final product, various treatment approaches were tested. A total of 10 strategies with different specific fungicide treatments for controlling Botrytis cinerea were applied to grapes at different growing stages: flowering, bunch closure and colour change. The type of vine chosen was Gamay, as it is very sensitive to Botrytis cinerea. In each experimental plot, disease incidence and severity were assessed at harvest. In addition, pesticide residue analysis was carried out on grapes, musts and wines to monitor residue levels in each treatment and to follow changes at each stage of the wine-making process. A correlation was established between the efficiency of anti-Botrytis fungicide treatment and pesticide residues in wine. Several strategies using various fungicides showed good results in terms of treatment efficiency while minimizing pesticide residues in wine, thus providing interesting alternatives to limit the development of fungal resistance.     

Assessment of grey mould (Botrytis cinerea) impact on phenolic and sensory quality of Bordeaux grapes,musts and wines for two consecutive vintages

Background and Aims: The impact of grey mould (Botrytis cinerea (B. cinerea)) was quantified on chemical, phenolic and sensory qualities of grapes, derived musts and wines. Methods and Results: Analyses were carried out by using naturally or artificially infected grape berries at ripeness or overripeness. In grape seeds, chemical analyses revealed no major differences between healthy and rotten grapes. In grape skins of Botrytis‐affected berries, concentrations of all the phenolic compounds (anthocyanins and proanthocyanidin monomers, dimers and trimer) decreased drastically. Mean degree of polymerization of the proanthocyanidin polymeric fraction was also affected in skins. Chemical analyses of musts and wines made with different percentages of rotten berries showed a moderate impact of the pathogen on their phenolic composition. Nevertheless, sensory analyses underlined a loss of wine sensory quality perceptible from a threshold as low as 5% of Botrytis‐affected grapes onwards. Conclusion: Phenolic variations and the associated negative impact in grapes, derived musts and wines may be related to oxidation phenomena from B. cinerea. The main effects of severity/age of grey mould and the level of berry maturity are also discussed. Significance of the Study: B. cinerea drastically affects the phenolic and organoleptic properties of grape skins and derived wines. Therefore, prophylactic actions early in the vineyard, evaluation of the sanitary status of the harvested grapes and berry sorting are primordial even under low disease pressure.     

石参多糖的体外抗氧化活性研究

采用水提醇沉法提取石参粗多糖,通过比色法测定石参多糖对羟自由基（.OH）、超氧阴离子（O2-.）、过氧化氢（H2O2）和2,2-二苯基苦基苯肼自由基（DPPH.）的清除率,并与VC进行比较,从而对石参多糖的抗氧化活性进行研究。结果表明,石参多糖具有一定的体外抗氧化能力,与阳性对照VC相比,石参多糖对H2O2有较强的清除能力,对DPPH.、.OH和O2-.具有不同的清除活性,清除率与石参多糖浓度呈正相关性。     

病虫害生物防治技术最新研究进展

综述了天敌昆虫、昆虫性信息素、植物源农药、微生物制剂、转基因技术在烟草病虫害生物防治方面的最新进展。分析认为生物防治具有无污染、无公害、长效等优点,将成为烟草病虫害综合防治体系的重要组成部分。     

柑橘精油成分分析及对灰葡萄孢菌的抑制作用

该研究采用水蒸气蒸馏法和有机试剂浸提法提取温州特早熟蜜橘橘皮精油,利用气相色谱-质谱联用(GC-MS)技术分析橘皮精油组成成分。以从福州周边果园收集草莓病果分离所得灰葡萄孢为研究对象,研究两种精油抑菌性能。结果显示：蒸馏油共鉴定出39种成分,醛类6种,烯萜类20种,醇类9种,酯类2种,酮类1种,有机酸1种;浸提法精油共鉴定出25种成分,烯萜类20种,醇类3种,烷烃类2种。柠檬烯为精油主要成分,水蒸气蒸馏法含量为82.37%,浸提法含量为85.25%。其次为γ-松油烯(7.78%,6.08%)、β-月桂烯(2.56%,2.06%)、α-蒎烯(1.35%,1.04%)。两种精油对灰葡萄孢最低抑菌体积分数分别为2.5%和5%。体外抑菌实验表明,精油能够通过对灰葡萄孢的菌丝、生长量、孢子萌发率、细胞透过性,诱导细胞死亡。草莓抑菌实验表明柑橘精油能够抑制灰葡萄孢在草莓果实上的生长,减缓果实的腐烂进程。其中,蒸馏油优于浸提油的抑菌效果。     

Structural Characterization and Antifatigue Effect In Vivo of Maca (Lepidium meyenii Walp) Polysaccharide

Maca (Lepidium meyenii Walp) polysaccharides (MP) with purity of 99.2% were obtained to investigate their structural characteristics and antifatigue effect in vivo. The physicochemical properties of MP were analyzed through high‐performance gel filtration chromatography, IR, monosaccharide composition, methylation, GC‐MS, and NMR analyses. The antifatigue effect of MP was evaluated by using a mouse weight‐loaded swimming model. MP is an acidic heteropolysaccharide with an average molecular weight (M_w) of 793.5 kDa. It is composed of D‐GalA: D‐Glc: L‐Ara: D‐Man: D‐Gal: L‐Rha = 35.07:29.98:16.98:13.01:4.21:0.75 (mol, %). The findings revealed that MP contained β‐1,3‐Galp(A), β‐1,3‐Glcp, and α‐1, 3‐Manp linked alternatingly to form a backbone (5:4:1). MP (above mid‐dosage 50 mg/kg bw/d) could effectively elongate swimming durations and accelerate average swimming speeds (within the 1st 5 min) of mice (P < 0.05) and improve the serous biochemical parameters of mice. Compared with the control model, high‐dosage (100 mg/kg bw/d) MP treatment could significantly enhance glutathione peroxidase and creatine kinase activities (P < 0.05) and decreased lactate dehydrogenase activity (P < 0.01). High‐dosage MP could significantly reduce the levels of blood urea nitrogen, lactic acid, and malondialdehyde (P < 0.05). MP is an acidic polysaccharide with a high D‐GalA content, which could be responsible for the antifatigue effect of maca.     

不同药剂防治烟蚜及烟草黑胫病试验研究

对按一定比例配制的吡虫啉WP与甲霜灵锰锌WP的复配剂进行了田间药效试验研究。结果表明 :所用复配剂 3个浓度对烟蚜及烟草黑胫病均有很好的防治效果 ,且与各对照单剂吡虫啉 ,甲霜灵锰锌防效差异不显著。从综合防效及降低药剂成本等因素考虑 ,以复配剂 30 0 0g/hm2 的效果最理想。     

fps基因过量表达对烟叶类胡萝卜素生物合成的影响

为探索法呢基焦磷酸合酶(FPS)基因过量表达对烤烟叶片类胡萝卜素生物合成的影响,利用RT-PCR技术,比较了4个fps转基因株系(K4、K-6、K-17、K-35)及其非转基因对照中参与类胡萝卜素生物合成的关键酶基因的表达强度,并利用LC/MS技术,分析了叶片发育过程中类胡萝卜素及其各组分含量的变化规律.结果表明:外源fps在烟草中的过量表达,对烟叶类胡萝卜素合成相关基因Psy、Lycb皆有正向调节作用,但对Zds的表达影响不大;化学分析表明fps转基因烤烟株系中,总类胡萝卜素及其各组分的含量在叶片不同发育期均高于未转基因K326对照株系.说明外源fps基因在烟草中的过表达,对类胡萝卜素生物合成具有促进作用.