Performance of Different Apple Cultivars in a Young High Density Orchard

The aim of the study was to evaluate the suitability of rootstock and cultivar combinations for high density orchards in northern climate conditions like in Latvia. In 2009, a trial was established with rootstocks M.9 and B.396 in combination with seven cultivars. The density of trees reached 2500 trees per 1 ha. The yields and the observed yield efficiency of all cultivars during the first four production years were larger on rootstock B.396. Also, average trunk diameter was slightly larger on this rootstock. On both rootstocks cultivars, ‘Gita’ and ‘Ligol’ had larger part of total yield formed on previous year shoots. These cultivars had more vigorous trunks as well. In the orchard at the given density, on both rootstocks thinner trunks and smaller yields were observed for cultivars with poor branching, like ‘White Transparent’ and ‘Konfetnoye’. ‘Rubin’ (Kazakh cv.) had low yield, this cultivar produces very large fruits on the ends of shoots. Lower average yields were also obtained for cultivars that produce fruits on spurs of older branch sections, like ‘Antei’ and ‘Kovalenkovskoye’. Summer cultivar ‘Konfetnoye’ had relatively smaller fruits. Rootstock B.396 and scab resistant cultivar ‘Gita’ showed best performance in the high density orchard.