利用SPAD-502对高山杜鹃氮素营养的快速诊断研究

Rapid Nitrogen Diagnosis for Rhododendron‘Furnivall's Daughter' Using SPAD-502

利用SPAD-502型叶绿素计测定了不同氮水平下高山杜鹃不同生长时期、不同叶位的SPAD值,分析SPAD值与叶绿素含量和叶片总氮含量的关系。结果表明,不同生长期第1轮和第2轮叶片的SPAD值与叶绿素含量均呈显著线性正相关,其中新梢生长期第1轮叶片的SPAD值与叶绿素含量的相关性最强,而叶绿素各参数中对SPAD值影响最大的是叶绿素b的含量。在不同氮水平下,SPAD值及相对叶色差与单位干重的总氮含量具有显著线性正相关关系,SPAD值的变化能够反映60%的单位干重叶氮含量的变化。因此,可以利用SPAD-502型叶绿素计对高山杜鹃进行快速、无损的氮素营养诊断。

Leaf chlorophyll meter readings （SPAD） of Rhododendron‘Furnivall’s Daughter’under different nitro-gen levels at different growth stages were analyzed by SPAD-502.The relationship between SPAD and content of leaf chlorophyll , and the relationship between SPAD and nitrogen content in leaf were analyzed . The results showed that despite of growth stage , the SPAD of the leaves at different positions were positively correlated with the contents of chlorophyll .Among which , the SPAD of the first whorle leaf and the content of chlorophyll was the most correlated , among different parameters of chlorophyll , chlorophyll b had the most significant effect on SPAD . Under different nitrogen levels , SPAD values and relative leaf color （ RSPAD ） showed significant positive linear correlations with total nitrogen content per unit mass （ Nm ） . The changes of SPAD values could explain 60 %changes of Nm .The study results showed that it was feasible conduct rapid and non-invasive nitrogen diagnosis on Rhododendron by using SPAD-502 .