Influence of chemical prunning on biomass and root system development in Pinus pinaster Ait. and Pinus radiata D. Don

Abstract

In relation to the stability problems found in many plantations, this work studies the effect in the nursery of different cultural practices, with the purpose of improving seedling quality. Two of the most commonly used species for afforestation purposes in the Cantabrian cornice in the last years were grown in the nursery: Pinus pinaster Ait. and Pinus radiata D. Don, using three different containers (Forest Pot 250, Cetap 54-Universal and Planfor) and covering the walls of the first two ones with CuCO3 in different concentrations (0, 1.5, 3, 4.5 %). Both species showed different response to copper treatment depending on the container, beeing P. pinaster the less sensitive species as regards to allometric modification. In general, copper treatment in P. radiata produced higher diameter, height and shoot biomass. We found statistically significant differences in the height to diameter ratio, for both species. All these circumstances produced finally a root system architecture modification in copper treated plants. Chemical prunning has demonstrated to be an effective method for rectifying some limitations derived from root system deformations, which are a consequence of using closed-walls containers for plant production.