EFFECTS OF DIFFERENT REGULATED AND SUSTAINED DEFICIT IRRIGATION STRATEGIES IN ALMOND PRODUCTION

The effects of six different levels of water depths, applied during the growing season, on the production (yield) of mature almond trees were evaluated during four consecutive years in Albacete (Central Spain). The irrigation treatments applied were: T1, no irrigation with the exception of one irrigation needed to keep the trees alive; T2, which was irrigated by applying 25% of potential crop evapotranspiration (ET_c) during the whole season (sustained deficit irrigation, SDI); T3, regulated deficit irrigation (RDI) treatment received 50% of ET_c, however during the kernel-filling period irrigation was 15% of ET_c; T4, SDI treatment which was irrigated by applying 50% of ET_c; T5, RDI treatment received 100% of ET_c, however during the kernel-filling period irrigation was 20% of ET_c and T6, which was irrigated to satisfy the entire demand of ET_c. Results indicate that, statistically there were significant differences (P<0.05) in yield and irrigation water use efficiency (WUEI) among treatments.
The optimum yield response was observed in treatment T6 during the four years of the study period and reached an average maximum yield of about 1,260 kg ha^-1. There were no significant differences (P>0.05) in almond production and WUEI between RDI and SDI strategies.
Although yield reductions for treatments T4 and T5 were significant (23% for T4 and 31% for T5 less than T6), the water savings obtained (50% for T4 and 55% for T5 of that applied with respect to T6) may encourage the adoption of SDI and RDI strategies in areas where a large portion of irrigation water comes from aquifers that are threatened by over exploitation.

VI International Symposium on Almonds and Pistachios

F. Mañas, P. López-Fuster, R. López-Urrea

Prunus dulcis, regulated deficit irrigation, sustained deficit irrigation, water use efficiency

https://doi.org/10.17660/ActaHortic.2014.1028.64