First Report of Myrothecium roridum Causing Leaf Spot on Anthurium andraeanum in China

A new severe disease on Anthurium andraeanum Lind. was observed in the summer of 2011 in Beijing, China. The fungus was isolated from symptomatic leaves, and its pathogenicity was confirmed. Based on the morphological characteristics and molecular analysis, the pathogen was identified as Myrothecium roridum Tode ex Fr. This is the first report of M. roridum causing leaf spot on A. andraeanum in China.     

红掌茎段侧芽离体快繁技术研究

以红掌嫩茎为外植体,诱导侧芽萌发,并进行增殖和生根培养,研究不同生长调节剂浓度配比对茎段侧芽萌发、增殖、无菌苗生根的影响以及增殖培养过程中愈伤组织的抑制等因素。结果表明,侧芽诱导的适宜培养基为MS+6-BA 2.0 mg/L+NAA 0.5 mg/L,萌发率达87.5%;最适增殖培养基为MS+6-BA 0.8 mg/L+NAA 0.2 mg/L+VB2 8.0 mg/L,增殖系数3.8;最适生根培养基为1/2MS+NAA 0.5 mg/L,生根率98%;在增殖培养基中添加适量VB2能较好地抑制愈伤组织的生成,防止愈伤组分织分化形成芽,从而达到以芽繁芽的目的。     

高温胁迫影响红掌生长发育的研究进展

红掌原产于南美洲热带雨林, 其具有色彩艳丽的佛焰苞, 在适宜的条件下可周年开花, 是一种具有极高观赏价值的盆花和切花植物。夏季高温严重影响红掌的生长和观赏价值, 增加了红掌的种植成本。对高温胁迫影响红掌外观形态、光合作用、细胞膜热稳定性、渗透调节物质、保护酶活性进行了讨论分析, 对高温褪色机理及其应对措施进行了归纳总结, 以期为进一步开展红掌耐热生理的研究和筛选抗高温种质资源提供参考, 对解决红掌的高温褪色问题有着重要的现实意义。     

Isolation of clean and PCR-amplifiable DNA fromAnthurium andreanum

A DNA extraction procedure that does not require hazardous materials, such as CTAB, phenols, or liquid nitrogen, was optimized forAnthurium andreanum, a plant rich in polysaccharides and polyphenolics. Three DNA isolation techniques were tested. The modified Rowhani protocol (1983), with slight modifications, was found to yield up to milligrams of DNA suitable for RAPD from spathe and leaf tissues. High-quality DNA was obtained readily from spathe tissues, while a spermine precipitation step was found to be essential when DNA was extracted from the leaf tissues.     

Latent infections of in vitro anthurium caused by Xanthomonas campestris pv. dieffenbachiae

Latent infections of tissue-cultured Anthurium andraeanum Lind. caused by the blight pathogen, Xanthomonas campestris pv. dieffenbachiae (McCulloch & Pirone) Dye, were examined. The pathogen survived in or on callus for over 4 months without producing symptoms in callus or turbidity in the medium. The pathogen survived for more than 1 year on or within stage II shoots without producing symptoms and was successively transferred three times as latently infected shoots were multiplied. The pathogen did not grow or survive for more than 2 weeks in Murashige and Skoog medium lacking plant material. The addition of coconut water enhanced bacterial growth and produced turbidity in culture media. Latently infected in vitro anthuriums may be inoculum sources for subsequent outbreaks of the disease.     

日光温室冬季增施CO2对切花红掌光合作用及生长发育的影响

针对切花红掌日光温室冬季生产时CO₂亏缺严重的现象,以不增施CO₂为对照,研究了增施700、1000、1300 μmol·mol^-1浓度CO₂对切花红掌‘火焰’光合特性和生长发育的影响.结果表明: 增施60 d CO₂,红掌叶片的净光合速率、胞间CO₂浓度和水分利用效率均显著提高,且以1000 μmol·mol^-1处理的增幅最大;而气孔导度则较对照显著下降.增施CO₂后,红掌叶片的可溶性糖、淀粉和可溶性蛋白含量均较对照显著增加,佛焰苞大小、色泽、花茎长度等切花品质参数,以及叶片发育质量参数和花茎生长速率均有不同程度的提高,且均以1000 μmol·mol^-1浓度最佳.增施1000 μmol·mol^-1的CO₂可以有效促进日光温室切花红掌的冬季生产.     

花烛胚性悬浮细胞玻璃化超低温保存条件研究

为建立适宜的花烛(Anthurium andraeanum Lind. )胚性悬浮细胞玻璃化超低温保存技术,采用单因素实验方法对影响玻璃化超低温保存后细胞相对存活率的主要因素进行了研究.结果表明,经玻璃化超低温保存后花烛悬浮细胞的相对存活率与悬浮细胞的继代培养时间、渗透调节剂的种类和浓度及预培养时间、装载液种类和预处理时间、PVS2脱水时间以及超低温保存后的化冻温度均有一定的关系.继代培养3和5 d,细胞的相对存活率较高(约20%);分别以0.3、0.5、0.7 mol·L-1山梨醇和60、80、100、120 g·L-1蔗糖为渗透调节剂预培养0～4 d,以0.5 mol·L-1山梨醇预培养2 d的效果最好,细胞的相对存活率为26.2%;用体积分数25%PVS2预处理15 min,细胞的相对存活率最高(29.0%);分别用体积分数100%PVS2脱水0、5、10、15、20、25和30 min,其中脱水10 min的悬浮细胞相对存活率最高(32.1%);分别在10 ℃、20 ℃、30 ℃、40 ℃、50 ℃和60 ℃水浴条件下进行化冻处理,其中用40 ℃水浴化冻的悬浮细胞相对存活率最高(32.1%).花烛胚性悬浮细胞玻璃化超低温保存和化冻的适宜流程为:将继代培养3～5 d的胚性悬浮细胞团(直径2 mm)在含0.5 mol·L-1山梨醇的1/2MS液体培养基中预培养2 d后,于4 ℃条件下处理24 h,然后先用体积分数25%PVS2室温预处理15 min,再用体积分数100%PVS2 在0 ℃条件下脱水10 min,最后迅速投入液氮中冷冻保存;将经过冷冻保存的细胞置于40 ℃水浴中化冻3 min,用含1.2 mol·L-1蔗糖的1/2MS液体培养基洗涤3次(每次10 min),之后即可进行恢复培养.     

花烛突变体叶色嵌合性状的分化特征与保持方法

以花烛品种‘Sonate’(Anthurium andraeanum‘Sonate’)的叶色嵌合型无菌苗为材料,对顶芽失去嵌合性状的16个单株分别进行单芽培养,观察侧芽及茎基部再生过程中叶色嵌合性状的分化特征;并据此归纳花烛突变体叶色嵌合性状的保持方法。结果表明:处于增殖和生根阶段的花烛突变单株侧芽再生植株的嵌合率分别为25.0%～75.0%和25.0%～66.7%,总的嵌合率分别为48.4%和47.8%,具有嵌合性状的侧芽再生植株均萌发于嵌合叶片的叶腋处;处于生根阶段的突变单株的茎基部也能再生出嵌合植株,嵌合率为33.3%～80.0%,总的嵌合率达到64.7%。研究结果显示:通过单芽离体培养的方法可以解决花烛突变体顶芽叶色嵌合性状消失的问题,且应用侧芽再生(增殖与生根阶段)或基部再生(生根阶段)的方法可以保持突变植株的嵌合性状。     

Efficacy of hot water drenches of Anthurium andraeanum plants against the burrowing nematode Radopholus similis and plant thermotolerance

Hot‐water drench treatments were evaluated for disinfesting roots of potted anthurium Anthurium andraeanum of the burrowing nematode Radopholus similis. A continuous drench of roots and media in pots with 50°C water for 5 to 20 min eliminated or reduced nematode populations to < 1 g^?1 of dry root. A second hot water drench, 2 months after the first drenching, tended to increase the efficacy of the heat treatment. A few survivors persisted in the roots and/or stems of a few plants 2 to 4 months after heat treatment. Non‐treatment of the shoots and possible migration from stem to root tissues are probable causes of nematode survival. Drenching potting media and roots in pot were as effective against R. similis in the roots as hot water dipping bare‐rooted plants. Plant response to hot‐water drenching varied among cultivars, but most exhibited tolerance to the heat treatments. Visual inspection of the plants showed little difference between treated and untreated plants in the heat tolerant cultivars. However, all heat‐treated ‘Marian Seefurth’ plants, especially hot water‐dipped bare‐rooted plants, appeared to suffer some degree of growth reduction as measured by lower root and stem dry weights when compared to untreated plants 3 months after treatment. Conditioning anthurium plants with hot water or hot air prior to hot water drenching did not benefit plant quality when compared to unconditioned, heat‐treated plants.