Abstract

Knowing the root growth is a fundamental aspect to evaluate the performance of a fruit orchard by understanding the development pattern of the aboveground growth including yield and fruit quality. During 2006-2007 research was carried out in the vineyards of the locality of La Junta (28° 3’ 3” S, 69° 57’ 37.8” W, 1218 m altitude), Atacama Region, Chile, separately in two soil types, medium and coarse texture. Eight Thompson Seedless plants were selected, selfrooted, 20 years old, divided into four highly productive individuals and four of low production potential. For each site, the design was completely randomized with two treatments (high and low productive potential), with four replications per treatment, being the experimental unit the plant. On each experimental site a frontal pit was excavated (perpendicular to the vine row) and performed a detailed mapping, based on location and category in diameter of all roots present in the soil profile. It was found that in medium-textured soils, and due to the high frequency and time of irrigation (15 200 m3 ha1 year), functional roots of vines are located preferably away from the zone of saturation of the wetted area, avoiding probably events of hypoxia and anoxia. In coarse-textured soils fine roots are found evenly distributed in the profile; in addition, vines of more productive potential are associated with a higher number of roots.