Effect of different water deprivation levels, applied during the pre-flowering period, on vegetative, reproductive and yield traits of olives trees

PIERLUIGI PIERTANTOZZI; MARIELA TORRES; BODOIRA ROMINA; DAMIÁN MAESTRI

San Juan

Simposio; VII International Sympossium of Olive Growing; 2012

Instituto Nacional de Tecnología Agropecuaria. Universidad Nacional de San Juan. CRILAR-CONICET. CREA. Universidad Nacional de Cuyo

The improvement of water useefficiency in olive cultivation is an issue of vital importance, withenvironmental and economic implications. In Argentina, the climatic pattern ofthe olive production areas is characterized by a marked water deficit duringwinter and spring months. An irrigation experiment was carried out in an oliveorchard 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 cropevapotranspiration), plus a control treatment at 100 % of Etc during all year.Data from the first crop year showed that water deficit reduced significantlythe 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 weremainly due to differences in fruit maturity at the time of harvest. A strongdrop in flowering, fruiting and yield parameters was observed during the secondcrop year. As a result, a marked difference in fruit production was foundbetween the first (?on?) and the second (?off) crop years, suggesting a strongalternate bearing pattern for both olive varieties analyzed. The maintenance ofthe fully-irrigated condition throughout the whole irrigation experiment didnot sustain fruit yield performance in the second year. The low production ofless irrigated treatments was insufficient to compensate induction of buds fromone year to other. Results clearly showed that pre-flowering ? floweringphenological phases are affected markedly by water availability indicatingstrong crop sensitivity to water deficit in such period.