The drought response of two peach cultivars with different fruit maturation periods, 'Ufo‑3' and 'Fergold', grafted onto the interspecific hybrid almond × peach rootstock 'Garnem', was evaluated during summers 2015 and 2016 in an experimental plot located at Murcia, Spain. After fruit harvest, the trees were subjected to of 5 days without irrigation, followed by a re‑watering period of 5 days. The tree water status, the gas exchange, as well as the foliar abscisic acid (ABA) accumulation were evaluated. A decrease in soil water content (SWC) was verified, which caused the reduction of midday leaf water potential (LWP) and the induction of stomatal closure. Once irrigation was restored, the water status of stressed trees was recovered. A negative strong correlation between the LWP and the intrinsic water use efficiency (iWUE) was found only in 2015, suggesting a possible drought tolerance strategy that allowed maintaining the photosynthetic capacity, despite the low values of stomatal conductance (gs) and the LWP. On the other hand, the stomatal closure regulation observed in stressed trees is not caused by the accumulation of ABA. This agronomic evaluation will allow a better understanding of the possible effect of the 'Garnem' rootstock on the physiological and biochemical adaptation to drought and its behaviour in recovery period on arid field conditions of the grafted peach cultivars.

Bielsa B, García‑Brunton J, Sanz MA, Rubio‑Cabetas MJ (2019). Caracterización de la respuesta adaptativa a sequía de dos cultivares de melocotonero en condiciones de aridez. ITEA‑Información Técnica Económica Agraria 115(4): 307‑325. https://doi.org/10.12706/itea.2019.010