Relationship between chlorophyll content and SCMR of diverse sugarcane genotypes in stalk elongation stage

Abstract

To date, the knowledge of the relationship between chlorophyll content and SPAD chlorophyll meter reading (SCMR) of diverse sugarcane genotypes during stalk elongation phase have been lacking. Therefore, the objective of this study was to indicate the relationship between chlorophyll content and SCMR of 22 diverse sugarcanes during elongation stage. Pot experiment was conducted at Agronomy research station, Faculty of Agriculture, Khon Kaen University. Completely Randomized Design (CRD) with 4 replications was used, diverse 22 genotypes based on typical and growth performance were assign as treatments. Chlorophyll content and SCMR were measured at 120 days after planting, and growth characters namely height and tiller numbers were recorded at 120 and 150 days after planting. The relationship between chlorophyll content and SCMR of 22 genotypes were found at elongation stage, positive correlations addressed between SCMR value and total chlorophyll (r = 0.70**), chlorophyll a (r = 0.69**) and chlorophyll b (r = 0.44*) contents. However, correlation coefficient value between SCMR and chlorophyll b was low. As the result, SCMR value feasibly use to evaluate the difference of total chlorophyll and chlorophyll a contents among diverse sugarcane genotypes. In addition, there were positive correlation between total chlorophyll content and chlorophyll a, and between total chlorophyll content and chlorophyll b, whereas the relationship between chlorophyll a and chlorophyll b was not significant. Despite correlation between SCMR and height growth rate was found, but its correlation coefficient value was low and unacceptable. This information would be useful for screening total chlorophyll content and chlorophyll a especially in sugarcane breeding program with massive population work.