云南片烟感官质量与香味成分关联分析

[目的]研究云南片烟感官质量与香味成分的关联关系,改善片烟质量.[方法]以云南片烟为研究对象,采用灰色关联分析方法,分别以不同类别致香成分、具体香味成分为出发点,探索影响片烟香气质量的主要因素.[结果]分析表明,8种致香成分中与香气质、香气量和评吸总分关联程度最高的为醛类、氮杂环类和酮类,其中醛类物质己醛、糠醛和5,5-二甲基-3-氧基-1-环己烯-1-甲醛与香气质、香气量和评吸总分的关联程度最高并且关联序一致.氮杂环类物质吡啶、吡略、2-甲酰基吡啶3种与香气质、香气量和评吸总分之间的关联程度最高;其中吡啶与香气质、香气量和评吸总分的关联程度最高.酮类物质与香气质、香气量和评吸总分的关联程度排序不尽相同,其中羟基丙酮对香气质、香气量和评吸总分的影响程度最大.[结论]在片烟致香成分与感官质量特别是香气质量研究中,可以重点关注醛类、氮杂环类和酮类物质,对己醛、糠醛、5,5-二甲基-3-.氧基-1-环己烯-1-甲醛、吡啶、吡咯、2-甲酰基吡啶、羟基丙酮和2,3-戊二酮等致香成分.     

灰关联熵在长江中游杂交油菜新品种选育中的应用

运用灰关联熵分析方法,对11个2017～2018年度长江中游区国家油菜新品种的农艺性状与单株产量的灰关联熵分析,结果表明,各性状与单株产量的熵关联度为：硫苷0.9793,菌核病发病率0.9808,菌核病发病指数0.9806,株高,0.9863,有效分枝数0.9734,单株有效角数0.9876,角粒数0.9848,千粒重0.9807,单株产量0.9894;熵关联顺序为：单株产量、单株有效角数、株高、角粒数、菌核病发病率、千粒重、菌核病发病指数、硫苷、有效分枝数,为长江中游区杂交油菜品种选育指明方向。     

钢筋抗拉强度检测中的误差与不确定度

介绍不确定度的基本概念和数学模型，并对材料力学性能测试中常见的钢筋抗拉强度检测中的不确定度进行了简要的分析和评定。     

Failure of UV irradiation to reduce blue mould infections beneficially in an experimental water handling system for pome fruit

A reduction in the number of wounds of pears and apples which developed blue mould (Penicillium expansum) infection was associated with reduced spore concentration. An experimental ultraviolet irradiation treatment of water in a fruit-handling system reduced both spore numbers and fruit rots, but not to a level which would suggest that the technique is worth pursuing to a commercial application stage.     

实验室制粒机

实验室制粒机主要为大专院校、科研单位,在实验室内压制各种规格的颗粒饲料,作饲养试验用。制粒机的研制试验结果表明,各项性能指标和制造质量均已达到设计要求,而在其使用的方便性和配套性方面超出了进口样机。     

Genetic analysis and molecular characterisation of laboratory and field mutants of Botryotinia fuckeliana (Botrytis cinerea) resistant to QoI fungicides

BACKGROUND: QoI fungicides, inhibitors of mitochondrial respiration, are considered to be at high risk of resistance development. In several phytopathogenic fungi, resistance is caused by mutations (most frequently G143A) in the mitochondrial cytochrome b (cytb) gene. The genetic and molecular basis of QoI resistance were investigated in laboratory and field mutants of Botryotinia fuckeliana (de Bary) Whetz. exhibiting in vitro reduced sensitivity to trifloxystrobin. RESULTS: B. fuckeliana mutants highly resistant to trifloxystrobin were obtained in the laboratory by spontaneous mutations in wild‐type strains, or from naturally infected plants on a medium amended with 1–3 mg L^?1 trifloxystrobin and 2 mM salicylhydroxamic acid, an inhibitor of alternative oxidase. No point mutations were detected, either in the complete nucleotide sequences of the cytb gene or in those of the aox and Rieske protein genes of laboratory mutants, whereas all field mutants carried the G143A mutation in the mitochondrial cytb gene. QoI resistance was always maternally inherited in ascospore progeny of sexual crosses of field mutants with sensitive reference strains. CONCLUSIONS: The G143A mutation in cytb gene is confirmed to be responsible for field resistance to QoIs in B. fuckeliana. Maternal inheritance of resistance to QoIs in progeny of sexual crosses confirmed that it is caused by extranuclear genetic determinants. In laboratory mutants the heteroplasmic state of mutated mitochondria could likely hamper the G143A detection, otherwise other gene(s) underlying different mechanisms of resistance could be involved. Copyright © 2012 Society of Chemical Industry     

改进的灰GM(1,1)模型在灌区水文年型中长期预报中的应用

在改进灰GM(1,1)模型的基础上,结合水文年型的划分标准,对三义寨引黄灌区不同水文年型做了中长期预报。检验表明,在灰预报值覆盖的范围内包含有多年实际发生的水文年型,结果有一定的可靠性。     

莴笋根茎部病害的病状特征及防治措施

对莴笋灰霉病、腐败病、软腐病这3种常见莴笋根茎部病害的病原、侵染循环、流行规律、危害症状进行了探讨,最后提出相应的综合防治措施。     

番茄叶霉病侵染机制及抗性机理研究进展

番茄叶霉病是由Cladosporium fulvum(Cook)Ciferrd引起的一种世界性病害。自从20世纪80年代以来,随着保护地番茄面积的扩大,该病的危害也越来越严重,成为了番茄生产上的重要叶部病害,严重影响番茄产量和品质。综述了近年来在番茄叶霉病侵染机制、生理小种的分化和抗病性机制方面的研究进展,并对其抗性研究前景进行了展望。     

碳酸钠和碳酸氢钠对番茄壮苗和灰霉病的防治作用

以番茄品种L402幼苗为试材,研究外源喷施碳酸钠和碳酸氢钠对番茄生长和灰霉病的防治作用。结果表明:25mmol·L~(-1)和50 mmol·L~(-1)的碳酸钠与碳酸氢钠对番茄幼苗具有显著的壮苗作用;30～60 mmol·L~(-1)的碳酸钠和碳酸氢钠对灰霉菌菌丝生长具有不同程度的抑制作用,且抑制作用通常随着浓度的升高而加强;30～40 mmol·L~(-1)的碳酸钠和50～60mmol·L~(-1)的碳酸氢钠对番茄灰霉病具有良好的预防作用;50 mmol·L~(-1)的碳酸钠和50～60 mmol·L~(-1)的碳酸氢钠对番茄灰霉病具有良好的抑制作用。生产上可应用适宜浓度的碳酸钠和碳酸氢钠防治番茄灰霉病。