锯叶棕体细胞胚胎发生及植株再生体系的建立

从锯叶棕成熟种子中成功实现体细胞胚胎发生和植株再生。成熟种子放在MS培养基上培养，加入0.15%活性炭，452 μmol/L 2,4-D和14.7 μmol/L N6-2iP，所有成熟合子胚培养5周后长出体胚簇，12周后，外植体转移到2,4-D浓度减到90.4 μmol/L的MS培养基中进行体胚增殖，之后体胚转移到含有0.9, 9 μmol/L TDZ或没有生长调节剂的基本培养基中转化成小植株。9 μmol/L TDZ对植株再生是无效的，然而，在0.9 μmol/L TDZ中作次培养有12%胚胎能长成完整植株，没有生长调节剂中35%胚胎长出嫩枝，这些嫩枝转移到含有22.2 μmol/L NAA的培养基中全部都会生根。picloram和2,4-D对锯叶棕幼苗愈伤的诱导效果最佳，6-BA次之，对子叶来说，picloram和2,4-D对愈伤的诱导起不到任何作用，而对茎尖的诱导效果最好。     

巴西橡胶树花药体胚发生类型及其培养条件的改良

橡胶树花药培养体胚发生率低及植株再生频率低是制约其组培苗工厂化生产的瓶颈。以热研7-33-97品系花药为外植体,研究橡胶树花药体细胞胚发育过程并对其体细胞胚进行系统分类,同时改良其培养条件。结果表明,完整的体胚发育过程是球形胚-心形胚-鱼雷胚-子叶胚,但有些心形胚不能进一步发育成鱼雷胚,在后继培养中会分化成畸形胚;体胚发生不具同步性,在鱼雷胚旁又长出次生胚。胶树花药体细胞胚共分9种类型,发现胶树花药体胚发生过程中产生连体胚现象,该类胚能正常发育成植株。不同胚状体培养条件对植株再生率的影响说明,暗培养诱导胚状体2个月后再转移至500 lx弱光照条件下培养10～15 d,然后再转移至出苗培养基培养,能够显著提高植株再生率。在诱导胚胎发生培养基中添加不同浓度的稀土,结果表明,稀土具有提高橡胶树花药体胚发生率的效果,其中以添加1 mg/L稀土培养效果最佳。     

不同菜用大豆品种的胚胎发生与再生

以8个菜用大豆品种的未成熟子叶为外植体,在MS(附加高浓度2,4-D)培养基诱导愈伤组织形成、体细胞胚胎发生与再生植株.结果表明:八个菜用大豆品种的未成熟子叶均可诱导产生愈伤组织与体细胞胚胎发生,出愈率为14.71%～100%.体细胞胚胎发生率变化在0～36.76%之间,绿子叶菜用大豆没有形成体细胞胚.体细胞胚可正常萌发产生小植株,移栽成活结实.菜用大豆的出愈率和体细胞胚胎发生率与基因型有关.     

铁兰体细胞胚的诱导及植株再生

以铁兰无菌苗为外植体,研究不同激素配比对铁兰胚性愈伤组织诱导及体细胞胚形成的影响,并对体细胞胚的发生过程进行形态学观察.结果表明:2,4-D对铁兰胚性愈伤组织的诱导具有重要作用,诱导铁兰胚性愈伤组织的最适2,4-D浓度为2.0 mg/L;胚性愈伤组织在含ABA的培养基上可分化形成体细胞胚.形态及解剖学观察表明,愈伤组织既可以产生于外植体的外层细胞,又可产生于外植体的深层细胞.体细胞胚的形态发生经历了与合子胚形态发生相似的阶段,即经过球形胚、子叶形胚等.胚经过萌发、芽的伸长和生根后形成再生植株.     

不同木薯品种体细胞胚及芽器官发生能力的研究

通过对不同优良木薯品种体细胞胚胎及芽器官发生能力进行比较研究。结果表明,不同品种之间的体细胞胚胎和芽器官发生能力因基因型不同而差异显著。KU 50体细胞胚发生率最高,为81.33%,其次为SC 205,诱导率为61.33%。而RYG 60未成功诱导出初生体细胞胚。诱导的体细胞胚经循环继代培养可形成次生胚状体。将次生胚状体转入成熟培养基,经光培养后可形成绿色的成熟体细胞胚,进而再生成植株。以KU 50体细胞胚萌发率最高,为42.2%。以子叶为外植体比以膨大的腋芽为外植体诱导初生体细胞胚的发生率高,除SC 205和NZ 199外,其余品种的诱导率均在85%以上。其中以新选048诱导效果最好,可达91.67%。将子叶切片置于器官发生培养基上可诱导不定芽的发生,诱导频率变幅为12.3%~71.0%,其中MCol 22和新选048诱导效果较好。     

可可体细胞胚胎发生及植株再生体系的构建

以可可（TheobromaCac0L.）的子叶为外植体,通过体胚发生途径,诱导再生可可植株。各培养阶段的优化培养基和培养条件为∶（1）愈伤组织诱导培养基（PCG）∶改良DKW+2,4-D3.0mgL+KT1.0mg几+TDZ 0.01mgL,在28+2）℃（以下培养温度均同）温度条件下,暗培养20d,诱导率为96.67%;（2）愈伤组织增殖培养基（SCG）∶改良DKW＋2,4-D 3.0mgA+KT1.0mg九,暗培养20d;（3）胚状体诱导培养基（ED）∶改良DKW+Sucrose30gL,暗培养60~150d,胚状体诱导产生并发育成熟,胚状体的诱导率为333%;（4）成熟胚诱导成苗∶①PEC培养基为∶改良DKW+Ghrose20gl+Sucrose10gL,光照为16h/d,培养60d;②采用RD培养基∶改良DKW+BA1.5mgl+AA0.5mgl,光照为16h/,培养3090d后,可得到完整的植株,再生植株的诱导率为 42%。     

花生子叶再生系统的建立

本实验建立了适应花育21号、22号、23号、24号的高频再生体系,以当年收获花生种子子叶为外植体接种MS 6-BA20μmol/L 2,4-D7.5μmol/L,14 d后产生丛生芽,芽诱导率达91.5%,平均每个外植体产生7个丛生芽。20 d后转入MS 6-BA2μmol/L诱导伸长,然后转入MS培养基生根获得再生植株。     

基因型和2,4 D浓度对小麦不同外植体离体培养特性的影响

为了探讨不同基因型、不同外植体和不同培养条件对小麦愈伤组织诱导、分化及再生的影响,以小偃22、西农1376、西农1012和西农1013为材料,对各小麦品种(系)的幼穗、花药、幼胚和成熟胚组织的培养特性及影响因素进行了研究.结果表明,愈伤组织的诱导和再生与外植体类型、基因型和培养条件密切相关.以幼穗和花药为材料,西农1376平均出愈率均最高,达98.97％和3.85％,成苗率和花培效率均值亦最高,达12.83％和2.39％;以幼胚为材料,西农1376平均出愈率也最高,达99.27％,西农1012平均成苗率最高,达51.03％;以成熟胚为材料,小偃22平均出愈率最高,达93.22％,西农1376平均成苗率达19.78％.离体培养条件下,不同小麦品种(系)的4种外植体愈伤诱导和分化率与2,4-D浓度密切相关,1.0～3.0 mg·L-1 2,4D浓度能较好地诱导4种离体组织愈伤的产生及分化.不同基因型和同一基因型的不同外植体在2,4-D最佳诱导浓度上也有差异.供试小麦4种离体组织培养再生特性比较表明,离体幼胚培养再生效率最高,成熟胚次之,幼穗最差.     

二步培养和AgNO3对甘蓝型油菜子叶和下胚轴芽再生的影响

以甘蓝型油菜（Brassica napus L.）品种“浙双758”为材料,研究二步培养及添加AgNO3对甘蓝型油菜子叶和下胚轴外植体离体再生的影响。外植体先在含0.5-1.5 mg/L 2,4-D的MS培养基上 “预培养”3 d 或7 d诱导愈伤组织的产生,再转到含有3 mg/L BA和0.15mg/L NAA及添加或不添加2.5 mg/L AgNO3的分化培养基上诱导芽的分化。结果表明,外植体愈伤组织诱导率和芽再生率与2,4-D浓度、预培养时间和AgNO3密切相关;分化培养基中添加银离子可显著增加不定芽的再生频率;二步培养及添加AgNO3可使半子叶、完整子叶和下胚轴外植体芽再生频率分别达到了96.1%,96.7%和96.7%。     

甘蓝型油菜带柄子叶高频率再生植株的研究

以甘蓝型油菜(Brassica napus)912品系带柄子叶为外植体,不同浓度6-BA与NAA激素组合的分化培养基诱导芽苗的分化,开展提高甘蓝型油菜带柄子叶再生频率的因素研究.发现甘蓝型油菜912品系带柄子叶在不同激素及浓度的6-BA与NAA组合中的再生频率、分化率存在显著差异.通过无菌苗苗龄、诱导分化前2,4-D的预培养以及添加AgNO3等因素的系统分析,结果表明甘蓝型油菜912品系带柄子叶在诱导分化前经过1.0mg/L 2,4-D的MS培养基中预培养3d,在最适培养基MS0 6-BA 4.0mg/L NAA 0.02mg/L 3.5mg/L AgNO3中,可较大程度地提高植株再生频率,再生频率和分化频率分别为70%和269.5%,初步建立了甘蓝型油菜912品系的高频率再生植株体系.     

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。     

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。     

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％。     

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.     

12份白花泡桐材料亲缘关系的ISSR分析

以‘福桐’、‘绿桐’2个无性系与10个不同种源的白花泡桐个体为研究对象，采用ISSR分子标记对12份白花泡桐材料的亲缘关系进行研究，并利用DPSv3.01进行聚类分析。结果表明：10条引物共扩增出66条条带，其中有37条多态带，多态性比例为56.1%。根据ISSR聚类分析结果，在遗传距离为0.35时，12份白花泡桐材料可分为5类，第1类为‘福桐’无性系与河南、河北种源个体；第2类为‘绿桐’无性系与湖南、湖北、江苏种源个体；第3类为浙江、广东种源个体；第4类为江西、福建种源个体；第5类为广西种源个体。此结果     

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。     

论长白山人参主要品种类型栽种方式及其商品分类

本文论述了长白山人参主要品种类型的栽种方式、总结其规范化种植的工艺流程、对各人参品种类型栽种方式、技术要点、品种退化的主要原因及其解决措施作了详细的研讨。强调指出人参的各种栽种方式必须实施GAP标准化管理才是最好的栽种方式。重点报告了人参主产区,最新最好的栽种方式。并对人参商品分类及野山参分等质量标准中的野山参、移山参的定义提出修改意见,为提高我国人参产品质量在国际市场上的竞争能力,保持人参产业可持续发展提供科学依据。     

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。     

Use of mechanics of cohesive granular media for analysis of hardness and vitreousness of wheat endosperm

The characterisation of the wheat endosperm by mechanical tests of compression highlighted a relation between the rupture energy and the elasticity modulus for different varieties of wheat; this relation allows us to distinguish mealy and vitreous endosperms. An approach based on the micromechanics of cohesive granular materials is used to analyse these experimental results. A geometrical model of the wheat endosperm made of grains linked by cohesive bonds is proposed. We introduced two parameters, the first one α represents the percentage of active bonds (bonds where the stiffness and strength are non-zero), and the second one β represents the threshold of the bond's rupture. The parameter β can be related to the cross-section of the bond. This model successfully describes the mechanical tests on the wheat endosperm. The comparison with the experimental tests makes it possible to clearly differentiate vitreous wheats and mealy wheats and then attribute this property to the parameter β. The model shows the same tendency as regards the evolution of the rupture energy and the elastic modulus with the parameter α. The modelling of endosperm by the mechanics of cohesive granular media provides a new theoretical framework to interpret the rheology of endosperm. This approach allows us to connect this rheology to the mechanical actions at the scale of the granules.