Propagation of pistachio applying in vitro culture techniques

Abstract

Pistachio grafting often shows a high degree of uncertainty, with variable and inconsistent results with commonly used rootstocks, producing irregular orchards and frequent regrafting. Besides, the size of the buds of pistachio cultivars far exceeds that of the juvenile rootstock terebinth (Pistacia terebinthus L.), widely used in Spain, making pistachio grafting difficult. Here, we have applied in vitro techniques to obtain reduced-size cultivars that match to the rootstock size. By reducing bud/scion of pistachio cultivars we can thus graft them on terebinth seedlings few weeks after germination. The female cultivars 'Larnaka', 'Kerman' and 'Sirora', as well as the male cultivar 'Peters' and the selection AD15 have been successfully cultivated in vitro. Grafting was performed on juvenile terebinth plants grown in small containers using a) micropropagated and acclimatized pistachio plants or b) in vitro grown shoot-tips as scion source. We have got up to 68% successful grafts with scions derived from in vitro techniques. Scions resumed growth few days after grafting, and time required to obtain new plants was significantly shortened.