A Nondestructive and Rapid Method for Estimating Leaf Area Broccoli

Abstract

Nondestructive and rapid methods to estimate leaf area from linear measurements are valuable tools when portable leaf area meters are not available. A model to estimate leaf area for one population and one hybrid of Broccoli was developed in a previous experiment. Since leaf morphology may vary among different genetic materials, it is necessary to test the available models on other cultivars. The objective of the present study was to determine whether an existing broccoli leaf area model developed for one population and one hybrid would apply to other broccoli sources, and if not, to develop models for such sources; ten hybrids were used. In a previous work, a model based on the product of leaf length (L) times the leaf width at the widest point (W) was the best leaf area predictor in terms of coefficient of determination (R 2 = 0.99). The best equation based on a single measurement included W 2 and had less predicting ability (R 2 = 0.96) than the model based on L x W but required measurement only of the leaf width at the widest point. The model based on L x M fit the data of eight of the ten hybrids tested, and the model based on W 2 fit the data of nine of the ten hybrids. This study demonstrates that broccoli leaf area can be estimated by using models derived from linear measurements. The product of L x W was a good predictor for most genotypes, but not for all of them. W 2 was a good predictor for all of the hybrids used in this study, even though it was less precise than L x W.