供镁水平对杉木幼苗不同器官营养元素含量的影响

Effect of different magnesium treatments on nutrient element content in different organs of Chinese fir(Cunninghamia lanceolata) seedlings

以1年生无性系020杉木幼苗为试材,探讨高镁、缺镁和正常供镁(对照),即施用0、3、1 mmol·L-1Mg SO4对杉木幼苗不同器官(根、茎和叶)N、P、K、Mg含量及N∶P的影响。结果表明,杉木幼苗各器官Mg含量均随施用Mg浓度的提高而上升;新根各营养元素含量均高于其他器官,而老茎各营养元素含量均较低;高镁处理下,除新茎的生长主要受氮限制外,其他器官生长均受磷限制。影响杉木幼苗N、P、K、Mg含量和N∶P的差异性分析表明,N、P、K含量和N∶P主要受不同器官的影响,而Mg含量则受不同处理影响较大。杉木不同器官N、P、K、Mg含量和N∶P对不同浓度镁处理的响应机理不同。

One year old seedlings of Chinese fir（ Cunninghamia lanceolata） clone 020 were used as the experimental material to investigate the effect of different magnesium treatments on the contents of nitrogen（ N）,phosphorus（ P）,potassium（ K）,and magnesium（ Mg） in different organs（ roots,stems and leaves） of Chinese fir seedlings. The results showed that the N,P,and K contents and N ∶ P ratios were different under different treatments. Mg content in all organs of Chinese fir seedlings increased with increased magnesium application. The content of each nutrient element was higher in the new roots than that of the other organs,while the content of nutrients in the old stems was lower,with high Mg application,the growth of new stems was limited by N and the growth of other organs was restricted by P. The analysis of variance of N,P,K,Mg content and N ∶ P showed that the content of N,P,K,and N ∶ P were mainly influenced by different organs,while Mg content was mainly influenced by different Mg treatments.The response mechanism of N,P,K,and Mg content and N ∶ P in different organs of Chinese fir to different concentrations of magnesium treatments was different.