Rootstock effects on two sweet cherry cultivars in Central Chile

Preliminary research data is reported from a sweet cherry (Prunus avium L.) grower's orchard located in Central Chile (33°52' S, 70°41' W and 700 m altitude), with a planting density of 1481 trees/ha. In 2003 and 2004 (4 ^th and 5^th leaf), tree size, flowering chronograms, fruitfulness, specific crop load and fruit quality of 'Bing' and 'Lapins' were evaluated on 'Pontaleb', 'Colt', 'Cab 6P', 'MaxMa 14', 'Gisela 6' and 'Gisela 5' rootstocks. A tree size index (TSI) is proposed. Root growth was measured in rizothrons during the first season for all rootstocks. Specific crop load in 'Bing' ranged from 16 (on 'Colt') to 158 g/tsi (on 'Gisela 6') in the 4 ^th leaf and from 26 (on 'MaxMa 14') to 77 gr/tsi (on 'Pontaleb') in the 5^th leaf. These relations increased for 'Cab 6P', 'Pontaleb' and 'Colt' in the second season. In 'Lapins', specific crop load ranged from 51 (on 'Colt') to 199 gr/tsi (on 'Gisela 5' and '6') in the 4^th leaf and increased from 74 (on 'Colt') to 131 gr/tsi (on 'Pontaleb') in the 5 ^th leaf. Fruit quality has been good for all combinations in terms of fruit weight, soluble solids, firmness and acidity. Emphasis is given to understand each combination's reproductive behaviour and apply the best management practices to maximize production of high quality fruit.