Chlorophyll and nitrogen determination in coconut using a non-destructive method

Portable non-destructive meters are used to estimate foliar chlorophyll or nitrogen (N) concentrations for many crops. In this study, we calibrated chlorophyll meter (atLeaf) to estimate chlorophyll in coconut using data sets collected from wide-ranging field experiments involving plant type, cropping system, fertigation trial and soil type. The atLeaf chlorophyll meter provided good estimates for chlorophyll concentrations in coconut, with coefficients of determination greater than 0.81. The product is suitable for determining foliar chlorophyll concentration of coconut, which can serve as a generic indicator of moisture or nutrient stress. Detecting N deficiencies requires caution, because the wide range of foliage colors across genotypes does not reflect the relationship between chlorophyll index (CI) and N. Regardless, detection is good for a given genotype with different management options. The product has potential as a management tool for optimizing irrigation and fertilizer regimes in plantation crops.