Potential of new Prunus cerasifera based rootstocks for adapting under heavy and calcareous soil conditions

Five Prunus cerasifera (Myrobalan) based rootstocks, three already released (Adara, Ademir, and Myrobalan B) and two under selection (Miral 3278 AD, Myrobalan 713 AD), budded with two European plums (‘Reine Claude of Bavay’ and ‘Reine Claude Tardive of Chambourcy’) were assessed over sixteenth years at the Aula Dei Experimental Station under heavy and calcareous soil conditions. The adaptation variability of these rootstocks was expressed in tree survival, yield performance, leaf mineral concentration, fruit size and fruit quality traits. Myrobalan 713 AD and Myrobalan B rootstocks presented the highest tree mortality on both plum cultivars, whereas all trees budded on the rest of the rootstocks survived well exhibiting homogenous growth. For both plum cultivars, the less vigorous rootstock was Miral 3278 AD, having also the best agronomical performance (higher cumulative yield, yield efficiency and fruit size). Similar trend in terms of fruit production was also observed for the intermediate semi-vigorous rootstock Adara. Fruit quality traits such as flesh firmness, soluble solids content and titratable acidity were, in general, not significantly affected by rootstock. Independently of the cultivar, at the fifth year of planting all rootstocks induced optimum values of N, P, Ca, Mg, and Mn according to reference values, but lower Fe and higher K values than the optimum. However, at the sixteenth year of the study a different trend was observed, probably influenced by age and crop load of the trees. For both cultivars, rootstocks had optimum Mg, lower than the optimum N and Mn concentrations, while P was, in general, slightly higher than the optimum or close to the upper limit value in the optimum range. The results obtained in the present work showed the hybrid Miral 3278 AD as a good alternative to Myrobalan rootstocks based on its best long-term tree survival and good agronomical performance. Further work should be done with Miral 3278 AD using more intensive orchard plum systems.Financial support was provided by the Spanish grants AGL 2005-05533, AGL 2008-00283 and AGL 2011-24576 cofunded by FEDER and the Regional Government of Aragon (grant A44).Peer reviewe