In vitro propagation of select tomatillo (Physalis ixocarpa Brot. ex Horm.) plant families

Abstract

The objective was to propagate select Physalis ixocarpa plants in vitro, acclimatize them and describe their phenological cycle. The in vitro response of stem apices was evaluated in families from the Tecozautla 04, Manzano Tepetlixpa and Morado San Miguel varieties. The apices were cultured in a medium containing Murashige and Skoog inorganic salts (100 %), supplemented with 0.4 mg·L-1 thiamine, 60 mg·L-1 L-cysteine, 100 mg·L-1 myo-inositol, 0.5 mg·L-1 nicotinic acid, 0.5 mg·L-1 pantothenic acid, 3 % sucrose and 7 g·L-1 agar, without growth regulators and the pH adjusted to 5.7 ± 0.1. In vitro rooting was done for 30 days, with 16 h of light at 3,000 µmol∙m-2∙s-1. The variables evaluated in vitro were seedling height, vigor, callus presence, root length, and number of leaves, roots, stems and buds. Plants produced in vitro were acclimatized and transplanted in greenhouses to follow their phenological cycle. The variables evaluated in acclimatization and phenological cycle were plant height and number of leaves, buds, flowers and set fruits. A completely randomized design was used for the in vitro evaluation, and randomized complete blocks for the greenhouse. The families with the best morphogenic responses in vitro were Tecozautla 04 and Manzano, and in phenological development they presented greater plant height. In acclimatization, survival was 100 % in all clones. In vitro responses, acclimatization and phenology depended on the variety and families.