Vegetative Development: Total Leaf Area and Surface Area Indexes

Abstract

Canopy management determines canopy shape and spatial leaf area distribution which in turn determines vineyard productivity. There are two indexes evaluating vineyard productivity which involve leaf development: total leaf area – LAI – and external leaf area – SA –. The first one refers to total leaf area developed per m2 of soil while SA refers to the external leaves, assuming that most of photosynthesis – 90% – is carried out by those leaves. This chapter aims to provide a feasible methodology to calculate both LAI and SA under different training systems and cultivars in order to predict vineyard productivity or/and to make decisions along the season. Relations between main leaf nerve length (cm) and leaf surface area (cm2) are given for Airen, Albarino, Barbera, Cabernet franc, Cabernet sauvignon, Chardonnay, Godello, Garnacha, Graciano, Mencia, Merlot, Petit verdot, Pinot noir, Semillon, Syrah, Tempranillo, Treixadura, Verdejo and Viognier.