不同氮磷钾营养水平对铁皮石斛组培苗生长的影响

[目的]分析不同氮、磷和钾营养水平对铁皮石斛组培苗生长的影响,为其组培快繁及田间施肥管理提供参考依据.[方法]以铁皮石斛壮苗阶段的组培苗为材料,采用L9(33)正交设计研究培养基中氮、磷和钾三大元素含量配比对其株高、叶片数、新增根数、分蘖数和相对增重率的影响,并对其中影响显著的钾元素进行单因素多水平影响试验.[结果]极差分析结果显示,氮对铁皮石斛组培苗株高和分蘖数影响最大,钾对新增根数和相对增重率影响最大,磷对叶片数影响最大.方差分析结果表明,氮、磷和钾对铁皮石斛组培苗的叶片数及新增根数均无显著影响(P>0.05);氮对株高和分蘖数影响明显,以N2水平(氮30.0 mmol/L)的株高最高,N3水平(氮60.0 mmol/L)的分蘖数最多;钾对铁皮石斛组培苗相对增重率影响显著(P<0.05),以K3水平(钾20.0 mmol/L)的相对增重率最高.钾离子含量试验结果表明,在一定范围内,随着钾离子浓度的增加,组培苗的相对增重率呈上升趋势,以处理k5(钾40.0 mmol/L)组培苗的相对增重率最高.[结论]在铁皮石斛组培苗增殖阶段,培养基中最佳氮、磷和钾含量配比分别为60.0、1.2和20.0 mmol/L,在壮苗阶段,培养基中最佳氮、磷和钾含量配比分别为30.0、1.2和20.0 mmol/L.在铁皮石斛组培苗生产过程中,可在此含量配比基础上添加激素及其他有机或无机营养组分,以促进组培苗生长.

Effects of different nitrogen,phosphorus and potassium nutrition levels on growth of Dendrobium officinale tissue culture plantlets

[Objective]This experiment analyzed the influence of different combination ratios of nitrogen,phosphorus and potassium on growing Dendrobium officinale tissue culture plantlets,in order to provide reference for tissue culture and rapid propagation, as well as management of field fertilization. [Method]Tissue culture plantlets of D. officinale at strong-seedling stage were used as experimental materials. Effects of different combination ratios of nitrogen, phosphorus and potassium in media on plant height, leaf number, new root number, tiller number, relative weight gain rate were studied by means of L9(33) orthogonal design method. Single factor experiments with multiple levels on potassium which had signifi-cant effects were carried out. [Result]Range analysis results showed:nitrogen was the biggest factor affecting plant height and tiller number; potassium had the largest impact on new root number and the relative weight gain rate; phosphorus in-fluenced leaf number the most. Variance analysis results indicated that:amount of nitrogen,phosphorus and potassium had no significant influence on leaf number and new root number (P>0.05); nitrogen level had obvious impact on plant height and tiller number,and the plantlets grew in N2(nitrogen 30.0 mmol/L) were the highest, plantlets in N3(nitrogen 60.0 mmol/L) had the largest tiller number. Potassium level had significant impact on relative weight gain rate (P<0.05) and the plantlets grew in K3(potassium 20.0 mmol/L) gained the largest relative weight gain rate. Potassium ion con-centration experiment showed that, within a certain range, relative weight gain rate increased as potassium ion concentra-tion rised, and relative weight gain rate of the plantlets increased and the ones in k5(potassium 40.0 mmol/L) was the largest. [Conclusion]For D. officinale tissue culture plantlets at proliferation stage, the optimal concentrations of nitrogen, phosphorus and potassium were 60.0,1.2 and 20.0 mmol/L,at strong-seedling stage, the most appropriate concentrations were 30.0,1.2 and 20.0 mmol/L. Moreover, in the process of seedling culture,plant growth regulators,organic and inorganic nutrients can be added into the media on this basis.