In Vitro Adventitious Rooting of Carrizo Citrange Microshoots

Abstract

The objective of this work was to develop an efficient in vitro rooting protocol for one of the most commercially used citrus rootstocks in Spain, Carrizo citrange (Citrus sinensis L. Osbeck × Poncirus trifoliata L. Raf.). Single-node cuttings taken from greenhouse-grown plants were cultured in petri dishes containing basal Murashige and Skoog medium. Shoots from nodal stem segments were excised and cultured in a multiplication medium (basal medium supplemented with 1.8 μM 6-benzylaminopurine) to promote the development of axillary buds. Individual shoots (15 mm long) were treated with different hormones at several concentrations for root induction evaluations. The addition of activated charcoal (AC) to the culture medium was also explored. The addition of auxins to the culture medium enhanced rooting percentage. Optimal results were obtained when 1-naphthalene acetic acid (10.8 μM) and gibberellic acid (0.3 μM) were added to the culture medium. The addition of AC to the rooting medium resulted in negative effects on the percentage of rooted shoots but had a positive effect on number of roots per rooted shoot. Chemical names used: activated charcoal (AC); 6-benzylaminopurine (BA); 1-naphthalene acetic acid (NAA); gibberellic acid (GA3); indole-3-butyric acid (IBA)