Stomatal Density and Length for Breeding of Evergreen Azaleas (Rhododendron simsii Planch.)

The hentability of stomatal density and stomatal length has been studied for four evergreen azalea (Rhododendron simsii Planch.) cultivars with the aim to evaluate the possibilities of stomatal characteristics of parental plants for increasing the crown diameter – hence yield – of the offspring., A nearly complete diallel cross with reciprocals has been carried out with the four parental cultivars. Highly significant general combining ability (GCA) values of the parents were found for stomatal length and density, but not for the crown diameter. GCA values of crown diameters did not correspond with GCA values of either stomatal length or stomatal density. Therefore it was concluded that utilizing stomatal characteristics as a selection tool for an increased crown diameter (yield) in azalea., may not be feasible. Differences in crown diameter could not be explained from correlations with either stomatal density or stomatal length.     

Diversity of flower colours in Rhododendron simsii Planch. and prospects for breeding

Summary A survey of the flower colours present in evergreen azaleas, Rhododendron simsii Planch is given. The following colours occur: white, red, carmine red, pink, purple and lilac. Crosses can lead to greater diversity although no really new shades have resulted. Quantitative anthocyanin and flavonol determinations for the cultivars enable us to gain an insight into the possiblities of increasing these contents and thus obtaining new colours. The prospects of breeding for intensely red, yellow and blue cultivars are also reviewed.     

The influence of cytokinins and ionic strength of Anderson's medium on shoot establishment and proliferation of evergreen azalea

Shoot-tip explants of evergreen azalea cv. Fuchsia grown on Anderson's medium and containing different cytokinins produced the highest proliferation rate on a medium containing thidiazuron (TDZ). TDZ concentrations ranging from 0.23 to 2.3 M resulted in both good bud-break rate (4 to 5) and shoot quality (> 0.5 cm in length). Adding 2.3 M zeatin to Anderson's medium containing 0.23 or 2.3 M TDZ increased the number of axillary shoots/explant. However, increasing the zeatin concentration to 4.6 M resulted in a reduced shoot proliferation rate. A medium containing 1.15 M TDZ and 2.3 M zeatin resulted in an 18-fold increase for 'Fuchsia' and a 9-fold increase for 'Hino Crimson' after 6 weeks of culture. It was found that explants grown on a half-strength Anderson's medium with 87.6 mM sucrose generally had better shoot proliferation rate and shoot quality than at higher ionic strength.     

遮阴对迷人杜鹃种子萌发和芽苗生长的影响

为给迷人杜鹃的抚育管理提供参考,采用盆栽法人工模拟光照条件,探索不同遮阴处理对迷人杜鹃种子萌发和芽苗生长的影响试验。结果表明:迷人杜鹃种子萌发率和萌发指数在30%遮阴处理时达到最大,分别为90.00%和2.46;随着光照的减弱而逐渐减小,在80%遮阴处理下最小,为40%和0.27。弱光照对种子萌发进程有一定的延迟作用,萌发活力指数随着光照的减弱而减小。不同遮阴处理的迷人杜鹃芽苗具有较大的形态学可塑性,30%遮阴处理的芽苗胚根长、胚轴长、芽苗活力指数和幼叶宽均最大,分别比全光照提高60.71%、29.91%、52.26%和33.33%;80%遮阴处理最小,分别比全光照降低59.09%、54.88%、74.32%和66.67%。随着遮阴度的增加,幼苗的根系活力降低,而总叶绿素含量先上升后降低,根系活力以30%遮阴处理最大,为3.49mg/(g·h);MDA含量以80%遮阴处理最大,为13.42nmol/g FW;叶绿素含量以50%遮阴处理最大,为75.32μg/g。遮阴度为30%的光照环境有利于迷人杜鹃盆栽育苗。     

青海杜鹃属植物种质资源及园林应用

在了解青海野生杜鹃属植物种质资源调查现状的基础上,从中筛选出观赏价值较高的15种野生杜娟属植物,并对所选植物利用分层聚类的方法,研究其亲缘关系,分析其园林用途。     

杜鹃花组培快繁技术的研究

用野生杜鹃花的种子无茵发芽获得试管苗,然后用试管苗的叶片进行离体培养,用二步法建立杜鹃花的快繁体系。试验结果表明：诱导愈伤的最佳培养基是1／4Anderson＋2,4-D1mg／L＋TDZ0．1mg／L;芽诱导培养基是1／4 Anderson＋IBA0．1mg／L＋TDZ1mg／L＋2-IP0．5mg／L;生根培养基是1／4Anderson＋NAA0．1mg／L。     

文雅杜鹃组织培养研究

以文雅杜鹃1 a生半木质化茎段作外植体,以WPM为基本培养基,研究不同激素浓度和组合对文雅杜鹃不定芽诱导和生根的影响.结果表明:外植体在WPM+ZT 2.0 mg/L(单位下略)+IAA 0.5添加蔗糖30 g/L,琼脂4g/L,pH5.0的培养基上诱导率达83.33％;最佳继代培养基为WPM+ZT 0.8+NAA 0.05+蔗糖30 g/L+琼脂4g/L,pH 5.0;最适生根培养基为WPM+IBA 1.0+NAA 0.5+蔗糖30 g/L+琼脂7g/L+活性炭3g/L,pH 5.0,生根率为93％.     

西藏色季拉山杜鹃花种质资源的初步研究

色季拉山杜鹃花有２５个种及变种，其中７种分布于东坡，３种分布于西坡，４种分布于山顶地带，１１种在东西坡均有分布。其生境类型可分为林缘灌丛型、森林型、高山灌丛型３类，以森林型种类居多，占４８％。其观赏类群可分为香花类、团花类、雅致类和黄花类４群，以香花类和黄花类观赏价值最高，雅致类最易被驯化利用。     

甘肃高山杜鹃花引种驯化及栽培技术研究初探

从杜鹃花的野外采挖、栽培管理等方面就9种甘肃高山杜鹃花的引种栽培技术进行了初步研究。通过资源调查综述了头花杜鹃等9种甘肃高山杜鹃的分布及生境；根据对甘肃高山杜鹃花的引种驯化经验，简单总结出了野外引种和驯化栽植的方法，归纳了养护管理等一般栽培技术。     

黄花杜鹃挥发油化学成分及抑菌作用的研究

利用气相色谱-质谱(GC-MS)联用法对黄花杜鹃Rhododendron anthopogonoides挥发油的化学成分进行了研究.在最佳分析条件下,共分离鉴定出38个化学成分,其中主要成分为有机酸及其酯、萜烯类化合物、醇及甾族化合物等.对挥发油进行了抑菌试验,可对黄花杜鹃研究提供重要的理论依据.