Tissue culture of Physalis angulata L. (Solanaceae): techniques for micropropagation and germplasm long-term preservation

Abstract

Physalis angulata is considered an important crop in Mexico, established for commercial production due to its nutritional and medicinal properties. This study’s objective was to develop an efficient method for the mass multiplication of P. angulata and cryopreservation of apical meristems by droplet-vitrification. In vitro propagation was given in MS basal culture medium supplemented with 2.22, 4.43, and 6.65 μM 6-Benziladenine (BA) in combination with 2.32, 4.64, and 6.96 μM Kinetin (Kin). Root induction was obtained by dipping shoots in an auxin medium 1.07, 2.68, 5.37, and 8.05 μM 1-Naphthaleneacetic acid (NAA) or 1.41, 2.85, 5.70, and 8.55 μM Indoleacetic acid (IAA). The plantlets were acclimatized and transferred to the greenhouse. Results showed an efficient proliferation with an offshoot number of 6.57 ± 0.46 with 4.43 µM BA in combination with 2.32 µM Kin. Efficient rooting was obtained with 1.07 µM NAA with an average of 30.51 ± 0.94 roots. For cryopreservation, the effect of dehydration was evaluated by exposing shoot-tips to plant vitrification solution 2 at different times; 15, 30, 45, 60, and 75 min were tested before and after immersion to liquid nitrogen, and the highest percentage of regrowth (90%) was observed at 30 min. Experimental micropropagation by shoot proliferation system with cytokinins interaction (BA/Kin), rooting stimulation with auxins (NAA or IAA), successful acclimation, and cryopreservation by the droplet-vitrification procedure of Physalis angulata apical meristems.