丛枝菌根真菌对芋组织培养苗生长的影响

 于温室盆栽条件下研究了丛枝菌根(AM) 真菌Gigaspora rosea、Glomus mosseae 和Glomus versi-forme 对芋(Colocasia esculenta) 组织培养苗移栽成活率、矿质营养、光合速率及生长的影响。结果表明, 接种AM真菌能提高芋组织培养幼苗移栽成活率和叶片光合速率, 降低气孔阻力; 其叶片和根内氮、磷、钾含量和生长量显著高于不接种对照。认为接种有效AM真菌是促进组织培养苗健康生长的重要技术。     

SSR技术及其在果树上的应用

SSR(Simple sequence repeat)技术以其丰富的多态性、共显性遗传、重复性好和操作简便等优点日益受到重视,已成为植物遗传和育种研究中不可缺少的分子标记。对SSR技术的原理和特点作了简要的介绍,较详细地分析了如何获得SSR引物,特别是综述了果树上SSR引物的研究现状,同时将其与其它几种主要的分子标记进行了比较分析,认为SSR标记检测的位点多态性水平明显高于RFLP,而且重复性优于RAPD;着重介绍了SSR技术在果树种质资源和构建果树遗传图谱及基因定位等研究中的应用现状;指出SSR技术将在果树科研上起到重要的作用。     

Occurrence of Mirafiori Lettuce Virus and Lettuce Big-vein Virus in Relation to Development of Big-vein Symptoms in Lettuce Crops

Big-vein disease (BV) of lettuce has been attributed to infection by Lettuce big-vein virus (LBVV), vectored by the soil fungus Olpidium brassicae. The finding of a second soil-borne virus in lettuce, Mirafiori lettuce virus (MiLV), led to a re-investigation of the role of LBVV in big-vein disease, with evidence emerging that both MiLV and LBVV are vectored by O. brassicae, and that MiLV, not LBVV, is the cause of BV (Lot et al. (2002), Phytopathology 92: 288–293). The two viruses have coat proteins of similar size but have different morphologies and are serologically unrelated. We tested individual lettuce plants in BV-prone fields and protected crops in France and Italy for the presence of the two viruses, using DAS-ELISA and antisera specific for each virus. Both MiLV and LBVV were found at high incidence, often together but sometimes separately. Symptoms were frequently found to be associated with MiLV alone or both viruses, but rarely LBVV alone. However, no absolute correlation emerged, because sometimes MiLV was present in the absence of symptoms, and vice versa. To clarify the situation, individual lettuce plants were examined over a period of time in two further surveys. In surveys of protected crops in France, plants with big-vein were always ELISA-positive for MiLV, or else symptomless plants positive for MiLV were later seen to develop big-vein symptoms. Presence or absence of LBVV appeared to have no effect on symptom development. In surveys of open fields in Italy, all combinations were found: presence of both viruses, apparent absence of both viruses, or presence of each one alone, in plants that developed BV. At the end of the observation period, nearly all plants had BV and contained both viruses.     

肥城桃组培苗诱导、基因转化及其增殖

红里、白里是肥城桃的两个优良品种,但不耐贮藏。为试图利用基因工程解决这一问题,先通过组培将其胚、胚乳、子叶的愈伤组织分别诱导再生植株和芽剥离出茎尖培育成苗。再将肥城桃反义PG基因,通过农杆菌介导转化组培苗,转化苗在含卡那霉素培养基上筛选,获得抗卡那霉素的转基因苗。用研制的增殖培养基培养4～7周,一个苗可生长出14～18分枝的苗,解决了转基因苗获得率低的问题,也满足了对转基因株系进行检测和从组培室到温棚到田间果园过渡栽培和芽接的需求,提高了繁育速率。     

新疆美洲斑潜蝇寄主种类及适合度的调查

通过乌鲁木齐、昌吉等地调查，发现新疆美洲斑潜蝇的寄主植物计有17科55种，其中蔬菜28种(变种)、大田作物8种，花卉和草坪植物13种、野生植物6种。以豆科、葫芦科植物受害最重。应用欧氏距离法的系统聚类分析，研究了美洲斑潜蝇对14种常见寄主植物的适合度；将其划分为5个类型，即最优适宜寄主、良好适宜寄主、适宜寄主、稍次适宜寄主和非适宜寄主。为害虫的防治决策提供了科学依据。     

我国近年来水稻重大病虫害可持续控制技术重要研究进展——非化学控害技术研究

针对水稻病虫害防治中长期存在控害保产与生产无公害稻米矛盾比较突出的问题,研究提出了几种效果显著的非化学控害增产技术。其中,利用水稻遗传背景、对病虫抗感水平等差异显著的水稻品种多样性种植,控制稻瘟病的效果达42.12％～76.68％,抑制白背飞虱若虫数量增长效果明显,增产糯稻或优质稻600～1050 kg／hm²,平均增收约1 500元／hm²;稻鱼共育控制稻飞虱的效果为63.77％～86.89％,对纹枯病病株抑制率70.52％,控制稻田杂草效果为89.57％,平收获鲜鱼319.5～1 177.5 kg／hm²,水稻产量比对照区增产7.05％～10.11％;稻鸭共育控制稻飞虱效果63.73％～77.18％,控制稻螟效果30.11％,控制纹枯病效果19.33％～67.03％,对稻田杂草控制效果91.96％,减少施肥30.6％、农药59.3％,减少投入1 987.05元／hm²。     

宁夏毛乌素沙地退化草原恢复演替过程中物种多样性与生产力的变化

对宁夏毛乌素沙地退化草原种植不同林龄柠条Caragana korshinskii后物种的多样性、群落结构及草地生产力进行了研究,结果表明:种植柠条林对退化草地的植被恢复有积极的作用,植物群落的多样性随柠条林龄的增加而增加,而且随林龄年份的增加,群落结构更趋于稳定.草地生产力由于土壤储水量相对较高,表现为随林龄的增加,草产量受季节降水量变化的影响较小,相对稳定的趋势.     

广州石门国家森林公园野生观赏植物资源调查

通过野外调查和查阅文献资料,得出石门国家森林公园共有野生观赏植物122科267属377种,其中蕨类植物19科23属28种,裸子植物4科5属7种,被子植物99科239属342种。分析了石门国家森林公园野生观赏植物资源的基本特征和用途,并探讨其保护和开发利用。     

大型综合医院户外空间植物景观研究

为营造良好的医院户外空间,采用文献查阅和综合分析等方法对广州市3家大型综合医院的绿地植物景观进行研究。结果表明:3家医院共有植物116种,其中骨干树种和基调树种的重复率较高,乔灌比值偏小,常绿与落叶比相对合理,色彩应用设计合理。在交往空间的搭配中,广东省中医院的交往空间最丰富,广东省人民医院私密型空间较少,中山大学第一附属医院对病人户外交往空间考虑不够,空间应用的元素较为单一。     

安徽省珍稀植物新纪录

水禾属和水禾为安徽省植物分布新纪录属和种。该文介绍了采自安徽省无为县禾本科单种属珍稀植物水禾的主要形态特征、生态特性和繁殖方法。