1-MCP复合瓶插液对洋桔梗切花保鲜效果的研究

以洋桔梗[Eustoma grandiflorum (Raf.) Shinners]切花为试验材料,用1-甲基环丙烯(1-MCP)、蔗糖、柠檬酸(CA)、水杨酸(SA)和氯化钙(CaCl2)按五因素四水平的正交设计配制复合瓶插液,通过测定瓶插寿命、鲜重变化率、水分平衡值、相对电导率和POD活性,研究不同复合瓶插液的保鲜效果.结果表明:600 mg/L 1-MCP +400 mg/L CA+3％蔗糖+20 mg/L SA+100 mg/L CaCl2和800 mg/L1-MCP +100 mg/L CA+3％蔗糖+40 mg/L SA+200 mg/L CaCl2保鲜液处理,分别比对照明显延长瓶插寿命8.83和8.41 d,使切花鲜重、水分平衡值、相对电导率和POD活性变化比较缓慢,适于洋桔梗切花瓶插保鲜.     

龙船花切花瓶插保鲜液配方研究

通过测定龙船花瓶插寿命、鲜重、花瓣质膜透性和花瓣蛋白质含量,研究不同浓度配比的蔗糖、硫酸铝、漂白粉和抗坏血酸的保鲜液对龙船花切花瓶插寿命的影响。结果表明:75 mg/L硫酸铝+3%蔗糖+100 mg/L漂白粉+100 mg/L抗坏血酸为较理想的龙船花瓶插保鲜液,切花瓶插寿命比处理1延长5 d,其鲜重变化和蛋白质变化均比较缓慢,相对电导率上升也比较慢。     

大王龙船花切花保鲜剂研究初探

研究不同浓度的蔗糖、8-HQS、硫代硫酸钠、漂白粉及柠檬酸所配成的保鲜液对大王龙船花的切花保鲜效果的影响。通过对大王龙船花切花在瓶插期间的鲜重变化、开花率和败花率及瓶插寿命的观测，结果表明：8-HQS200mg／l＋2％蔗糖＋200mg／1柠檬酸的开花率高，衰败程度较低，花色较有光泽且观赏价值较高，并有效地延长瓶插寿命，是效果最佳的瓶插保鲜液。     

不同预处理对富贵鸟鹤蕉切花的贮运保鲜效果

通过不同预处理方法对鹤蕉‘富贵鸟’3个时期（蕾期、初花期、开花期）的花枝进行处理,研究富贵鸟鹤蕉切花的贮藏保鲜技术及贮藏过程中衰老生理的特性。结果表明：花枝在浓度为90g/L蔗糖＋1mmol/LSTS中浸泡9min的效果最佳;对不同采收期而言,采后贮藏寿命：蕾期〉初花期〉开花期,其中蕾期和初花期的贮藏寿命差异不显著,均可视为最佳采收期;富贵鸟切花衰老过程中,其花青素含量整体呈下降趋势,可溶性糖和可溶性蛋白含量也整体呈下降趋势,但对于某些处理的某一阶段稍有上升,POD酶活性从贮藏之日起,其活性呈不断上升趋势。     

不同保鲜液对黄花美冠兰切花生理及瓶插寿命的影响

通过不同浓度的蔗糖(SUC)、硫代硫酸银(STS)和八羟基喹啉柠檬酸(8-HQC)组合对黄花美冠兰3个采切期(第Ⅰ、Ⅱ、Ⅲ采切期)花枝的处理,研究了黄花美冠兰切花瓶插过程中的生理变化及瓶插寿命长短。结果表明:试验中以配方为10g/L SUC+100mg/L 8-HQC+3mmol/L STS的保鲜液应用于第Ⅱ采切期的黄花美冠兰切花的效果最佳,期望瓶插寿命达6.4d。3个采切期的黄花美冠兰切花在衰老过程中,EC值均呈上升趋势,其中第Ⅱ采切期EC值上升较缓慢;可溶性蛋白含量在第Ⅰ采切期和第Ⅱ采切期先升高后降低,在第Ⅲ采切期呈整体下降趋势。     

苯甲酸与赤霉素对中国水仙切花保鲜效果的影响

本研究以中国水仙‘金盏银台’切花为材料,在基础瓶插液（1%蔗糖）中分别添加不同浓度苯甲酸与赤霉素,通过观测切花的瓶插寿命筛选适宜的保鲜剂配方;同时测定了这一过程中切花的鲜重变化,丙二醛（malondialdehyde, MDA）、游离脯氨酸（proline, PRO）和可溶性蛋白质的含量,超氧化物歧化酶（superoxide dismutase, SOD）、过氧化物酶（peroxidase, POD）和过氧化氢酶（catalase, CAT）活性,分析保鲜剂发挥作用的生理生化基础。结果表明,1%蔗糖溶液添加200 mg/L苯甲酸的复合瓶插液可延长中国水仙切花瓶插寿命1.6 d;瓶插期间MDA含量呈上升趋势;瓶插过程中SOD和CAT活性、可溶性蛋白含量等高于同期对照组。1%蔗糖溶液添加200 mg/L赤霉素可延长切花瓶插寿命2.5 d;瓶插过程中SOD和POD活性、可溶性蛋白含量等高于同期对照组;但PRO含量在第15天较对照下降了40%。综合来看,1%蔗糖溶液添加200 mg/L赤霉素对中国水仙切花的保鲜效果最好。     

阿希蕉合生花组培快繁技术研究

阿希蕉为野生香蕉资源,可作为重要的遗传育种资源并具有观赏价值。本研究以阿希蕉合生花为植物材料,进行组培快繁技术研究。结果表明,阿希蕉在巴西蕉愈伤诱导培养基上可诱导出愈伤组织,最佳芽分化培养基配方为MS+6-BA（3.0 mg/L）+NAA（0.1~0.2 mg/L）,最佳芽增殖培养基配方为MS+6-BA（2.0 mg/L）+NAA（0.1 mg/L）,最佳生根培养基配方为MS+IBA（3.0 mg/L）+NAA（0.3 mg/L）。从取材到获得根系完整的组培苗约需100 d,繁殖效率100株/花苞以上,增殖效率高,可达到快速繁育的目的。     

抗坏血酸对非洲菊鲜切花瓶插保鲜的作用

该试验对抗坏血酸(以下简称VC)在非洲菊切花的保鲜效应进行研究。探讨非洲菊在不同浓度VC瓶插液中的保鲜效果。以期得出在瓶插液环境中合适的VC浓度。研究结果表明:与对照CK相比,处理1,处理2,处理3,处理4都能有不同程度地增加鲜重和延长瓶插寿命。并在弯茎现象上和对照相比都有一定程度的加强。其中处理4的效果最好。     

不同贮藏温度对桔梗花粉生活力及授粉结实能力的影响

以ME3+BK+100 g/L蔗糖+150 g/L PEG4000作为培养基,把桔梗新鲜花粉在不同的温度下进行培养,结果表明,30℃培养1.5 h为花粉萌发和花粉管生长的最佳培养条件。把桔梗花粉贮藏在不同的温度下,结果显示:低温贮藏可明显延长花粉的寿命,常温下花粉仅能贮藏4 d左右,但在10、4、-20℃下贮藏,花粉寿命可分别达60、90、150 d以上;随着贮藏时间的延长,花粉的授粉结实率均呈下降趋势,但低温贮藏可明显减缓结实率下降的速度。      

姜荷花‘红色印象’工厂化组培育苗技术研究

以姜荷花‘红色印象’植株的多个部位作为外植体,进行丛生芽诱导、增殖扩繁、生根壮苗以及出瓶移栽育苗的研究,完善姜荷花工厂化组培快繁流程,为其规模化生产提供参考。以姜荷花球茎、储藏根、球茎小芽、侧芽、幼嫩花芽、幼嫩叶片6个部位为材料,通过添加不同浓度6-BA和NAA的MS培养基,对丛生芽诱导培养、丛生芽增殖培养、生根壮苗以及移栽育苗等步骤进行优化。姜荷花‘红色印象’最佳外植体为球茎小芽和侧芽,诱导培养基为MS+6-BA (3 mg/L或5 mg/L)+NAA 0.2 mg/L+蔗糖30 g/L+卡拉胶7 g/L,最佳丛生芽增殖培养基为MS+6-BA3 mg/L+NAA0.1mg/L+蔗糖30g/L+卡拉胶7g/L,生根壮苗培养基选用1/2MS+NAA0.1mg/L+蔗糖20g/L+卡拉胶7 g/L,经过炼苗后出瓶移栽,组培苗种植基质选用细泥炭和细椰糠1∶1混合基质最佳,出瓶移栽成活率达95%以上,表型稳定。利用EST-SSR标记对母株和随机选择的组培苗进行扩增分析,证实DNA水平上无明显变异。通过对姜荷花‘红色印象’外植体和培养基的筛选,实现姜荷花组培快繁流程优化,建立高效完整的姜荷花工厂...     

Analysis of nutritional components of eight famine foods of the Republic of Niger

In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply.     

狗牙根诱变后代抗寒性评价

通过电解质外渗法和匍匐茎恢复试验对‘阳江’狗牙根及其12个通过形态鉴定选出的坪用价值高且花序密度低的诱变后代进行抗寒性鉴定。电解质外渗法结果表明:诱变后代间的抗寒性具有较大差异,其叶片半致死温度(LT₅₀)的变异范围为-7.6～-0.2℃(最低值与最大值相差7.4℃);参试材料抗寒性由强到弱依次为M18>M4>M26>M28> M22>阳江>M29>M31>M10>M37>M16>M1>M25,其中,有5个诱变后代抗寒性优于亲本,分别是M18、M4、M26、M28、M22。匍匐茎恢复实验结果表明:诱变后代M1、M22、M26、M31、M25在0℃和-5℃低温胁迫后的恢复生长率都高于亲本,恢复能力均优于亲本;M10、M37、M28在-5℃低温胁迫下,恢复生长能力低于亲本,抗寒性相对较弱,M16和M4在0℃和-5℃低温胁迫下,恢复生长率都低于亲本,抗寒性明显弱于亲本。综合2种方法鉴定结果显示:诱变后代M1、M25的恢复能力较强;M4、M28的叶片抗寒性较好,青绿期较长;M22、M18、M26的叶片抗寒性和匍匐茎恢复能力均较强;M29,M31的叶片抗寒性和匍匐茎恢复能力与亲本相似;M10、M16、M37的叶片抗寒性和匍匐茎恢复能力均较弱,整体抗寒性较弱。     

芦笋枯萎病病原鉴定

对造成福建省漳州市东山县的芦笋枯萎病病原菌进行分子鉴定,以期确定病原菌的属、种名,为防治该病害寻求理论依据。试验对分离纯化的病原菌核糖体DNA的ITS区进行测序,在Genbank中搜索其同源性并构建它们的系统发育树,结果表明：引起芦笋枯萎病的病原菌是镰刀属中的尖孢镰刀菌(Fusarium oxysporum),且病原菌之间的同源性高达89%,遗传差异不显著。     

橡胶树丛枝病病原的抗血清制备与应用

以感染橡胶树丛枝病病原的长春花为材料,制备得到橡胶丛枝病病原菌抽提液,以抽提液为抗原免疫家兔,制备抗血清,经微量沉淀测定,抗血清效价为１：２０４８。应用橡胶丛枝病抗血清检测橡胶褐皮病,无症苗木检出率达３０％－３７％,可疑的褐皮病树检出率达８５．７％。     

Mechanism of action of insecticidal secondary metabolites of plant origin

Insect pest management is facing the economic and ecological challenge worldwide due to the human and environmental hazards caused by majority of the synthetic pesticide chemicals. Identification of novel effective insecticidal compounds is essential to combat increasing resistance rates. Botanicals containing active insecticidal phytochemicals appear to be promising to address some of these problems. Therefore, there is a continuous need to explore new active molecules with different mechanisms of action. Secondary metabolites present in plants apparently function as defense (toxic), which inhibits reproduction and other processes. The phytochemical biomolecules could be used for maximizing the effectiveness and specificity in future insecticide design with specific or multiple target sites, while ensuring the economic and ecological sustainability. In this article, the current state of knowledge on phytochemical sources and insecticidal activity, their mechanism of action in insects, resistance, and promising advances made in phytochemical research are reviewed.     

Size and frequency of occurrence of pre-roost gatherings of starlings

One hundred and fifty-six pre-roost gatherings of starlings were observed at 28 sites around a roost in west Norfolk during winter. Pre-roost gatherings occurred more frequently at individual farmyards compared with individual fields, but 82% of the sites where gatherings occurred were on fields. The size of gatherings was greater, the closer to the roost. Birds in pre-roost gatherings on fields of autumn-sown winter wheat spent most of the time feeding and had a diet composed almost exclusively of wheat seeds. Birds in gatherings on grass fields also fed intensively whereas only 31% of birds at farmyards were feeding. The implications that these results have with regard to potential damage to fields of winter wheat and around farmyards are discussed.     

蝉拟青霉疏水蛋白PChyd基因表达模式分析及敲除载体构建

为深入研究昆虫病原真菌蝉拟青霉疏水蛋白PChyd基因的功能,根据蝉拟青霉基因组信息克隆疏水蛋白PChyd基因,对该基因序列进行生物信息学分析,使用qRT-PCR技术对其在不同培养条件或阶段下的表达模式进行分析,并通过酶切酶连的方法构建了该基因的敲除载体。结果表明：PChyd基因的开放阅读框序列全长303 bp,编码100 aa,包含22 aa的信号肽序列和70 aa疏水蛋白功能区域。系统发育分析显示该基因与粗糙虫草菌亲缘关系最近。qRT-PCR结果显示PChyd基因在PDA培养的菌丝体、诱导的附着胞、诱导的芽生孢子中表达量显著高于另外2个样品,其中芽生孢子表达量最高,暗示该基因在蝉拟青霉侵染初期和在昆虫血腔中定殖阶段可能具有重要作用。凝胶电泳结果表明,成功构建了该基因的敲除载体,扩增出含有上臂、HPH、下臂的3356 bp左右的片段。本研究为进一步探究蝉拟青霉疏水蛋白PChyd基因的致病机理、生防工程菌的改造奠定了基础。     

中耕方式对土壤理化特性及玉米生长发育影响研究Ⅰ.中耕方式对玉米生长发育的影响

2002～2003年在0～3次中耕条件下研究了中耕方式对玉米生长发育和产量形成的影响。结果表明,多次中耕增大了玉米倒伏率,降低了玉米最大叶面积指数、株高及各时期叶片叶绿素含量,对花粒期玉米净光合速率、气孔导度、蒸腾速率也产生一定的负面影响。少中耕有增产的趋势,并且可以降低生产成本、增加经济效益。     

波罗蜜叶片突变体叶绿素含量测定和超微结构观察

波罗蜜（Artocarpus heterophyllus）是一种热带果树,至今对其突变体的研究少有报道。本研究以波罗蜜叶片为试验材料,探究其叶片出现白化和返绿现象的可能原因。（1）用分光光度计法、比色法测定波罗蜜叶片突变体和正常绿叶的叶绿素及叶绿素前体物质含量;（2）用叶绿素酶Elisa试剂盒测定叶绿素酶活性;（3）用透射电子显微镜对叶绿体的超微形态结构进行观察。研究结果表明：（1）不同叶色所产生的叶绿素a含量、叶绿素b含量、叶绿素总含量、类胡萝卜素含量均存在显著差异;（2）波罗蜜叶片突变体和正常绿叶的叶绿素合成前体物质含量之间并没有出现显著性差异;（3）对波罗蜜叶片的叶绿素酶活性进行测定时,发现其活性出现显著差异,但对其叶绿素含量的差异性并没有产生较大影响;（4）观察波罗蜜叶片内叶绿体超微形态结构时,发现正常绿叶的叶绿体形态完好且数量较多,白化叶和返绿叶的叶绿体内部结构存在缺陷,其原因是叶绿体基粒构建阶段受阻;基于测定波罗蜜叶片中的叶绿素、叶绿素前体物质含量和叶绿素酶活性,并观察波罗蜜叶片内叶绿体的超微形态结构,对得到的数据结果进行比较分析。本研究推测是在叶绿素合成阶段,原脱植基叶绿素合成叶绿素时受阻及叶绿体发不良导致波罗蜜出现白化和返绿现象,为今后进一步综合研究波罗蜜突变体提供理论依据。     

农杆菌注射法瞬时转化荔枝果实组织的研究

为了寻找一种高效的荔枝果实瞬时基因表达方法,本研究以荔枝品种‘新球蜜荔’（Litchi chinensis Sonn. var. ‘Xinqiumili’）为试材,利用农杆菌注射法对荔枝果实组织进行转化,研究了果实发育时期、菌株种类、注射部位、取样时间、菌液浓度等对转化效率的影响。结果表明：选择果肉已完全包裹种子的Ⅱb期果实进行连体注射,在果柄、果皮、种子、果肉分别注入OD₆₀₀值为2.4的农杆菌菌株GV3101,4 d后取样进行检测,4个组织的GUS染色率较高。本研究成功建立了适用于荔枝果实的基因瞬时表达系统,为今后快速鉴定荔枝果实相关基因功能提供了基础。