Effect of Different Water Deprivation Levels, applied during the Pre-Flowering ? Flowering Period, on Vegetative, Reproductive and Yield Traits of Olives Trees (Olea europaea L.)

PIERLUIGI PIERANTOZZI; MARIELA TORRES; ROMINA BODOIRA; DAMIÁN M MAESTRI

San Juan

Simposio; VII International Symposium on Olive Growing; 2012

INTA,CRILAR-CONICET,UNSJ, UNCuyo, UCCuyo, UNDec, CREA, Gobierno de San Juan

The improvement of water use efficiency in olive cultivation is an issue of vital importance, with environmental and economic implications. In Argentina, the climatic pattern of the olive production areas is characterized by a marked water deficit during winter and spring months. An irrigation experiment was carried out in an olive orchard at Córdoba province (Argentina) during two consecutive crop years. During the pre-flowering ? flowering period four regulated deficit irrigation (RDI) treatments were imposed to olive trees (Olea europaea cv. Arbequina and Manzanilla) at 0, 25, 50 and 75 % of Etc (estimated crop evapotranspiration), plus a control treatment at 100 % of Etc during all year. Data from the first crop year showed that water deficit reduced significantly the current-year vegetative shoot growth, resulted in weakening of flowering, decreased fruit set and had a clear negative impact on tree productivity. Differences among treatments in oil, oleic acid and total phenol contents were mainly due to differences in fruit maturity at the time of harvest. A strong drop in flowering, fruiting and yield parameters was observed during the second crop year. As a result, a marked difference in fruit production was found between the first (?on?) and the second (?off) crop years, suggesting a strong alternate bearing pattern for both olive varieties analyzed. The maintenance of the fully-irrigated condition throughout the whole irrigation experiment did not sustain fruit yield performance in the second year. The low production of less irrigated treatments was insufficient to compensate induction of buds from one year to other. Results clearly showed that pre-flowering ? flowering phenological phases are affected markedly by water availability indicating strong crop sensitivity to water deficit in such period.