Dynamic of oil accumulation in relation to fruit growth and ripening from Arbequina and Manzanilla cultivars grown at two localities in Argentina.

ROMINA BODOIRA; MARIELA TORRES; PIERLUIGI PIERTANTOZZI; DAMIÁN MAESTRI

San Juan

Simposio; VII International Symposium on Olive Growing; 2012

Instituto Nacional de Tecnología Agropecuaria. Universidad Nacional de San Juan. Gobierno de San Juan.

Olive fruits fromcultivars Arbequina and Manzanilla were harvested at bi-weekly intervals inorder to: a) study the dynamic of oil accumulation in relation to fruit growthand ripening, b) analyze variations in oil content and fatty acid (FA)composition at two different growing areas (Córdoba province, Cruz del Eje Departmentand San Juan province, Capital Department). For Manzanilla cultivar, two weeksafter fruit setting, fruit weight began to increase quickly and continued untilmaturity index (MI) was around 1, after which it practically stopped. InArbequina, fruit weight increased at lesser rate reaching a plateau at MI near1.5. Olive cultivars growing at San Juan began to mature sooner. However,independently of the environment, once the ripening process started, Manzanillaripened at lower rate than Arbequina. For both olive cultivars, oilaccumulation began approximately four weeks after fruit setting. In Arbequina,oil content increased linearly until MIs near 2.5 (39% DWB, Córdoba) or 3-3.5(42% DWB, San Juan) were reached. In Manzanilla, oil accumulation adjusted tosigmoid type curves which reached a maximum (35% DWB) at MI near 2. Oleic acid(OA) content increased rapidly until 6-8 weeks after fruit setting. Later, OAsynthesis stopped and its concentration remained constant (Manzanilla) orgradually decreased (Arbequina). For each cultivar, there were not significantvariations between environments in AO contents throughout the sampling period.Linoleic acid accumulation pattern presented the opposite trend: it showed astrong decrease until 6-8 weeks after fruit setting; then, its contentincreased (Arbequina) or remained practically constant (Manzanilla). Regardinglinolenic acid, unusually elevated concentrations (7 ? 19 %) were found at thebeginning of fruit development. The levels of this FA strongly dropped (below 1%) until the beginning of the pit hardening period, and no significantvariations were found throughout the fruit ripening period. Each olive varietyshowed characteristic fruit growth and ripening patterns, which were associatedwith characteristic oil accumulation rate and FA composition. These parameterswere slightly influenced by environmental conditions of the olive growing areasconsidered.