Model-based estimation of the leaf area of ozone-indicator tobacco (Nicotiana tabacum L.) plants under ambient ozone conditions

Abstract

Bel-W3 is an ozone-sensitive tobacco (Nicotiana tabacum L.) cultivar widely used worldwide for ozone biomonitoring. Despite its extensive use, there is no comprehensive predictive model to non-destructively estimate the leaf area using only a common ruler, yet leaf area is a major evaluative trait in plants under ozone stress and of economic value in tobacco plants. In this method, we aimed at developing a predictive model to estimate leaf area using the product between leaf length and leaf width. To this end, we conducted a field experiment with ground-grown Bel-W3 plants treated with different solutions under ambient ozone conditions. The solutions were water, the antiozonant ethylenediurea (EDU; 500 ppm), and the antitranspirant pinolene (Vapor Gard; 1%, 5%, 10%). The chemical treatments were introduced to enhance leaves pool and capture different conditions that can occur in ozone biomonitoring projects. • A simple linear predictive model was developed and validated using data from a previous chamber experiment with small seedlings. • Overestimation of the model led to the integration of data from both experiments and development of another simple linear predictive model. • This integrated model provides improved estimation of leaf area and can be used for representative estimation of the area of Bel-W3 leaves of any sizes.

Keywords

• Bel-W3 leaf area calculation