A simple and accurate equation for estimating individual leaf area of eggplant from linear measurements

Summary Simple, accurate and non-destructive equations determining leaf area of plants are important for many experimental comparisons. Determining the individual leaf area (LA) of eggplant ( Solanum melongena L.) involves measurements of leaf parameters [length (L) and width (W)]. Two year investigation were carried out during 2005 (on five cultivars) and 2006 (on one cultivar) under open field and greenhouse conditions, respectively to test whether a equation could be developed to estimate leaf area across cultivars. Regression analyses of LA versus L and W revealed several equations that could be used for estimating the area of individual eggplant leaves. A linear equation having LW as the independent variable provided the most accurate estimate (R 2 =0.97, MSE=89) of eggplant LA, but double the time required for leaf measurement. The quadratic equation (LA=0.763 L+0.340 L) exhibited a high accuracy and precision (R 2 =0.92, MSE=220) in estimating individual eggplant LA. We preferred this equation because of its simplicity and convenience, as it only involves one variable. Validation of the quadratic equation having L of leaves measured in the 2006 experiment under greenhouse conditions showed that the correlation between calculated and measured areas was very high.