Abstract:

In order to discuss accuracy of determining chlorophyll with SPAD chlorophyll meter in the eecological field experiments, SPAD value, chlorophyll a, chlorophyll b and total chlorophyll content of Leymus chinensis on Hebei Guyuan and Neimeng Tumuji natural grassland were determined with SPAD chlorophyll meter and alcohol-acetone extraction method. The results showed that chlorophyll content and SPAD value of L. chinensis on different grasslands were changed in the certain range. The minimum value of SPAD value, chlorophyll a, chlorophyll b and total chlorophyll content of L. chinensis were 21.850SPAD, 2.611 mg?g-1, 1.125 mg?g-1, 3.738 mg?g-1, respectively. The max value of SPAD value, chlorophyll a, chlorophyll b and total chlorophyll content of L. chinensis were 46.150SPAD, 21.954 mg?g-1, 7.356 mg?g-1, 29.322 mg?g-1, respectively. Coefficient of variation was range from 20.457 to 36.921%. Chlorophyll a, chlorophyll b and total chlorophyll content of L. chinensis on Neimeng Tumuji natural grassland were higher than those on Hebei Guyuan natural grassland. On the contrary, SPAD value of L. chinensis on Neimeng Tumuji natural grassland was lower than those on Hebei Guyuan natural grassland. Regression Analysis showed that relationships between chlorophyll a content, chlorophyll b content, total chlorophyll content and SPAD value were significant linear, index and power function. Coefficient of determination was from 44.1% to 63.9. And the Coefficient of determination of linear function was highest than those of index and power function. SPAD502 chlorophyll meter can launch 660nm infrared light and 940nm near infrared light, which can reflect relative chlorophyll of plant. In result, chlorophyll content of L. chinensis Individual were different. Linear function could greatly reflect the relationships between chlorophyll content and SPAD value of L. chinensis. Chlorophyll content of L. chinensis can be accurately determined on field condition with SPAD chlorophyll meter. This method is Simple and fast on field experiment, providing theoretical basis for grass production.