Estimation of Leaf Area in Coneflower (Echinacea purpurea L.) Using Independent Variables

Document Type: Original Article


Department of Horticultural Science, College of Agriculture, University of Birjand, Birjand, Iran


Leaf area information is required in various horticultural and physiological studies and it will be more useful if done via non-destructive methods. The objective of this study was to establish equations to estimate leaf area (LA) using length (L), width (W), fresh weight (FW), dry weight (DW), length × length (L2), width × width (W2), length × width (L×W), length + width (L+W), fresh weight × fresh weight (FW2) and dry weight × dry weight (DW2) of coneflower (Echinacea purpurea L.) leaves as a medicinal and landscape plant. An open field experiment was carried out to study relationship between leaf dimension and weight with leaf area of this plant. Observed leaf area was obtained by an automatic measuring device and leaf dimensions were measured by a ruler. A linear model employing L × W as an independent variables [LA = 0.575 (L × W) - 0.934] resulted in the most accurate estimation (R2 = 0.874, RMSE = 2.33) of coneflower leaf area. Validation of the regression model showed that the correlation between measured and simulated values by using this equation was quite acceptable.

Graphical Abstract

Estimation of Leaf Area in Coneflower (Echinacea purpurea L.) Using Independent Variables


The highest R2 (0.874) and lowest RMSE (2.33) were obtained from equation LA = 0.575 (L × W) - 0.934.

A linear model employing length × width resulted in the most accurate estimation of coneflower leaf area.



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