Obtaining a compact orchard, with less vigorous plants and high production, constitutes a strong tendency in the current horticulture, aiming the raise of the productivity. One of the techniques for reducing vigor is the interstem. This study was developed in a commercial orchard of Randon Agro Silvo Pastoril S.A. (RASIP), located in Rio Grande do Sul State, Brazil. The purpose of this work was to evaluate the vegetative and productive development of apple trees cv. Imperial Gala with different lengths of EM-9 interstem. The treatments consisted of five interstem lengths: 10, 15, 20, 25, 30 cm. The following parameters were evaluated, in the seventh and eighth year of implantation: the sectional area of the Imperial Gala 5 cm above the second graft point; height of the plant; the tree-head size; fertility index; the number of fruits per plant; estimated productivity and productive efficiency. The use of interstem EM-9 of 30 cm in the rootstock Marubakaido is the most indicated for vigor control of Imperial Gala apple trees, provides greater productive efficiency and produces bigger fruits.
Mallus domestica Borkh; vigour reduction; rootstock
