杜鹃花新品种‘紫金粉玉’

‘紫金粉玉’是‘玉麒麟’与‘火花’杂交育成的杜鹃花新品种。花色为淡粉色;花径9.5~10.5 cm;花瓣5裂,裂深;雄蕊部分瓣化,上部裂片有醒目的深粉色斑点,花心绿色。植株长势强健,株形紧凑;耐高温高湿,适宜长江中下游地区棚室盆栽。自然始花期较早,为2月上中旬,持续20~25 d。     

重瓣杜鹃花新品种‘紫金艳后’

 杜鹃花‘紫金艳后’是‘小叶铁红’ב汉堡’杂交育成的重瓣新品种。花色艳红；雄蕊、花萼皆完全瓣化为花瓣；花径6.0 ~ 6.5 cm。植株长势强健，株形紧凑美观；耐高温高湿，适宜长江中下游地区设施栽培。自然始花期3月下旬至4月上旬，持续25 ~ 28 d。     

4个杜鹃品种的抗旱性比较及生理响应

以4个5年生杜鹃品种为试验材料,采用盆栽控水法研究杜鹃植株在不同干旱程度下的形态与生理响应。旱害指数结果表明:‘国旗红’抗旱性最强,‘玉蝴蝶’次之,胭脂蜜抗旱性最弱。随着干旱胁迫程度加深,杜鹃的相对含水量显著下降(P<0.05);丙二醛(MDA)含量、相对电导率随干旱胁迫程度加深呈上升趋势;而过氧化氢酶(CAT)活性、可溶性糖含量则因品种的不同而表现出不同的结果,‘国旗红’、‘大青莲’、‘胭脂蜜’的CAT活性在重度胁迫后下降,这时可能已经达到植株耐受干旱的极限,清除氧自由基的能力降低。通过相关性和主成分分析发现CAT活性、可溶性糖、MDA含量、相对电导率、相对含水量与杜鹃抗旱性密切相关。采用隶属函数法对4个杜鹃品种的抗旱性进行综合评价,结果表明,4个品种抗旱性强弱依次为‘国旗红’>‘玉蝴蝶’>‘大青莲’>‘胭脂蜜’,与旱害指数结果一致。     

两种杜鹃杂交种不定芽生根的培养基配方

以杜鹃杂交种R.simsii×R.mucronatum和R.pulchrum×R.mucronatum组培苗的不定芽为外植体,对基本培养基和蔗糖浓度采用单因子设计,对生长素种类和活性炭采用正交试验,对适宜的生根培养基配方进行了探讨。结果表明:不同的杂交组合适宜不定芽生根的培养基类型、蔗糖浓度及激素组合都有所不同。R.simsii×R.mucr-onatum的适宜生根培养基为1/2 WPM+20 g/L蔗糖+3 g/L AC,R.pulchrum×R.mucronatum的合适生根培养基为WPM+10 g/L蔗糖+2 mg/L IBA。适宜的移栽基质均为V泥炭∶V蛭石∶V珍珠岩=1∶1∶1。     

湖南杜鹃属植物野生资源多样性调查

对湖南杜鹃属植物进行野外调查、资料收集、标本鉴定,确定湖南自然分布杜鹃属植物62种1变种,隶属5亚属8组16亚组,其中特有种有13种.湖南杜鹃属植物资源种类较多,珍稀特有植物丰富,表型性状多样.     

不同处理方法对马缨杜鹃种子萌发和生长的影响

为探究马缨杜鹃种子萌发生长的最佳处理条件,应用不同方法处理种子.结果表明:马缨杜鹃种子用常温蒸馏水浸泡48 h萌发率最高,迟91.00%,发芽势达54.00%,是最佳处理方法;2.5%KNO3溶液处理,能促进种子萌发后胚根、胚芽的生长;70℃温水、硫酸、H2O2、CuSO4等处理种子萌发率低于50%,幼苗生长差.     

Effects of vegetation control on nutrient removal and Fagus orientalis, Lipsky regeneration in the western Black Sea Region of Turkey

Dense Rhododendron ponticum (L.) understories of eastern beech (Fagus orientalis Lipsky) stands in the Black Sea Region (BSR) of Turkey create challenging forest vegetation management problems relative to beech regeneration. Rhododendron traditionally is controlled in Turkish forests with grubbing and bulldozing. The effects of these practices on nutrient removal and natural beech regeneration have not been quantitatively studied. Two woody vegetation control treatments (bulldozing and hand-grubbing) were installed during late summer, 2002 in three mature beech stands with dense rhododendron understories in the Düzce Forest Management Directorate, in the Turkish western BSR. Aboveground biomass of each vegetation component, total aboveground vegetation biomass, nutrient concentrations, organic matter (OM) removal, and total amount of OM nutrients were determined for each woody vegetation control treatment. Soil bulk density and nutrient content, and beech seedling biomass, nutrient content, and natural regeneration also were studied. One year after treatment, the machine site preparation by bulldozing (MSP) that removed understory vegetation and attached roots, reduced mean forest floor OM content by about 84%, when compared to hand-grubbing. Mean soil C, N, K and Mg concentrations on the bulldozed sites were 36, 27, 50 and 55% less, respectively, than those on the grubbed sites. Total C and Mg amounts at the 5–10 cm soil depth were 24 and 47% lower, respectively, for mechanical site preparation (MSP) sites, when compared to grubbed sites. Overall, soil bulk density did not differ significantly between the grubbing and MSP treatments. Frequent passes on designated transects on MSP sites resulted in a significant (P < 0.01) one-third increase in bulk density of the first 20 cm soil depth, when compared to grubbed sites. No natural beech regeneration occurred on untreated control sites. Mineral soil exposure on the MSP sites increased beech seedling germination substantially. One year after treatment, the mean number of naturally regenerated seedlings for MSP sites was 2.5 times greater than for grubbed sites. Woody control treatments had significant effects upon beech seedling chemistry, with N, P, K, Ca and Mg concentrations averaging 35, 47, 12, 33 and 25% lower, respectively, for MSP sites, when compared to grubbed sites. However, mean seedling biomass and nutrient content were significantly greater (P < 0.05) on MSP sites. Long-term effects from windrowing on MSP site residues, associated topsoil and nutrients need to be evaluated.     

湖南平江幕阜山云锦杜鹃群落特征的分析

就湖南省平江县幕阜山云锦杜鹃群落的结构特征和动态特征进行了调查分析,结果表明:群落结构保存较为完整,立木分布均匀;云锦杜鹃的相对多度、相对频度和相对显著度均处最高值,其重要值为96.8,是该群落的建群种;该群落中云锦杜鹃种群的数量最多,其基径级结构呈正态分布,说明其尚处在相对稳定发展阶段.该群落是地带性珍稀群落,具有保护、开发和利用价值.     

贵州杜鹃属的5种新记录

本文报道了贵州杜鹃属Rhododendron L新记录的植物，它们是云上杜鹃 R. pachypodum Balf.f. et W. W. Smith朱砂杜鹃 R. cinnabarinum Hook. f. Rhodod 西昌杜鹃 R. sichangense I.J. Zhao,涧上杜鹃 R. subflumieum Tam 和白花杜鹃R. mucronatum （Blume） G. Don。     

Inheritance of Corolla Size, Number of Stamens and Percentage of Plants with Petaloid Stamens in Evergreen Azaleas (Rhododendron Subsect. obtusa)

Research has been carried out on the inheritance of corolla size, number of stamens and percentage of plants with petaloid stamens (double flower) in evergreen azaleas (Rhododendron Subsect. obtusa). For this purpose two incomplete diallel crosses were used. The first one included seven species and one cultivar and the second diallel 13 cultivars. In both diallels for all three characters the GCA mean squares were high. Also, the positive correlation between the parental values and the GCA estimates for flower size and number of stamens indicates that the expression of these characters is mainly determined by additive gene action. A negative correlation was found between GCA estimates for die n number of stamens and the percentage of plants with petaloid stamens. When breeding azaleas with large double flowers, parents can be directly selected on the basis of these characters since additive genetic variance dominates. As no genetic correlations were found between corolla size and number of stamens (percentage of plants with petaloid stamens) the breeding will not be hampered by unfavourable linkage of genes for these characters.