Tissue Culture of Betula microphylla Bunge var. paludosa

[Objectives]This study aimed to study the tissue culture technique of Betula microphylla Bunge var. paludosa. [Methods]Taking seeds as explant,seedlings of B. microphylla were cultured. Then,stem sections with leaves were cut off and subjected to induction of clustered shoots. Finally,the rooting and transplanting of adventitious shoots were completed. Thus,the tissue culture system of B. microphylla was established. [Results]The natural seed germination induction medium was Murashige and Skoog( MS),and the germination rate was31%. The most suitable shoot induction medium was WPM medium added with 1. 0 mg/L of 6-benzylaminopurine( BA),and the multiplication coefficient was 13. 7. The rooting medium was Woody Plant medium( WPM) added with 1. 0 mg/L of indole-3-butytric acid( IBA),and the rooting rate was 100%. The transplanting substrate for tissue-cultured seedlings was composed of humus soil,vermiculite and perlite( V∶ V∶ V =4∶3∶3),and the survival rate reached 88. 75%. [Conclusions]The experimental materials are easy to obtain and preserve,and the proliferation is rapid. This study provides technical support for the rapid acquisition of the tissue-cultured seedlings of B. microphylla.

NaCl和Na_2SO_4胁迫下沼泽小叶桦的生理响应

以沼泽小叶桦为对象,分析了不同浓度NaCl和Na2SO4处理下沼泽小叶桦叶绿素和脯氨酸、可溶性糖、蛋白质等渗透调节物质含量的变化。结果表明:沼泽小叶桦在NaCl作用下其叶绿素、可溶性糖和脯氨酸含量的变化与Na2SO4胁迫下相似,随着盐浓度的增加,叶绿素含量显著下降,可溶性糖和脯氨酸含量均显著增加;叶片蛋白质含量在较低Na+浓度下表现为先降低然后升高的趋势,在高浓度NaCl胁迫下蛋白质含量随着胁迫时间的增加逐渐下降;在相同浓度Na+处理时,NaCl胁迫下叶片生理指标变幅比Na2SO4胁迫时大,这可能与沼泽小叶桦因长期生长在以硫酸盐为主的环境下已适应一定浓度的硫酸盐有关。

沼泽小叶桦扦插技术研究

为研究不同因素对沼泽小叶桦硬枝和嫩枝插穗生根的影响,找到适合沼泽小叶桦扦插生根的方法,提高生根率,以多年生沼泽小叶桦实生苗作为试验材料,分别探讨激素种类、激素浓度、浸泡时间及木质化程度4个因子对沼泽小叶桦插穗生根率、生根长度和生根数量的影响。结果表明:嫩枝插穗生根率明显高于硬枝插穗;用200 mg/L的ABT-1+GGR的混合激素处理硬枝插穗10 h,插穗生根率最高达13.33%;嫩枝插穗浸泡在50 mg/L的ABT-1中20 min,生根率最高为60%;硬枝插穗的生根长度和生根数量最高分别为3.75 cm和6.51根;嫩枝插穗的生根长度和生根数量最高可达32.38 cm和14.06根。经过不同处理,找到了提高沼泽小叶桦生根的方法。

腐胺对沼泽小叶桦硬枝扦插生根和生长的影响

以沼泽小叶桦1年生硬枝插条为材料,研究了3种浓度腐胺(50、100、200 mg·L^(-1))和3种处理时间(5、30、120 min)下的扦插生根率、扦插苗的生长和生物量情况,旨在为沼泽小叶桦扦插育苗提供参考。结果表明:不同处理间的扦插生根率差异显著(P<0.05),腐胺50 mg·L^(-1)+30 min处理和腐胺100 mg·L^(-1)+5 min处理的扦插生根率最高,达92.2%;适宜的腐胺浓度和处理时间能提高沼泽小叶桦的扦插生根率,但对苗木地径、苗高、根长和各器官生物量的作用很小,影响苗木生长量的主要因子是光照条件和养分状况。