The development of in vitro propagation methods can improve the current commercial use and conservation of plants like naranjilla (Solanum quitoense), a distinctive Andean crop and key emerging agricultural product. In the present study, we report in vitro culture protocols for naranjilla apical buds, hypocotyls and petioles. In apical bud culture, MS medium supplemented with 0.10 mg l −1 1-naphtaleneacetic acid (NAA) produced longer plantlets with greater number of leaves. Hypocotyl culture yielded higher number of shoots when using older explants in MS medium supplemented with different combinations of NAA, 6-benzylaminopurine (BAP) and gibberellic acid (GA 3). Petiole culture produced a significantly higher number of shoots per explant, with more abundant and bigger leaves, when using MS medium supplemented with 0.02 mg l −1 NAA, 4.50 mg l −1 BAP and 1.00 mg l −1 GA 3. A factorial analysis reveals that the interaction between GA 3 and NAA/BAP plays an important role in shoot regeneration. These results provide new tools for the in vitro regeneration of naranjilla plants, improving on previously reported protocols for this species by using alternative explant types and regeneration protocols.

Shallots (Allium cepa var. aggregatum) are a type of onion which form several bulbs from a single basal disc. They are characterized by a high total solids content which improves their gastronomic and neutraceutical properties. Shallots (Allium cepa var. aggregatum) are a culinary staple with high commercial value in European, North American and South American markets. Their commercial production via vegetative propagation, however, is time-consuming and strongly affected by viral diseases. The aim of this study was to establish an in vitro apical meristem culture protocol for the regeneration of shallot plants. The efficiency of different regeneration and bulb-formation media were evaluated in this investigation. The best results for plant regeneration (68 % efficiency) were obtained with MS + 30g.L −1 sucrose + 1.5g.L −1 benomyl + 1.1uM NAA + 8.9uM BAP and for bulb formation (77 % efficiency) with MS + 10uM ancymidol and 50g.L −1 sucrose. Moreover, 50 % of all plants regenerated from apical meristems were effectively acclimatized. The protocol developed and standardized in this investigation can be used to increase the efficiency of shallot bulb-seed production for commercial applications.Keywords. Allium cepa var. aggregatum, apical bud, in vitro culture. ResumenLa cebolla chalote (Allium cepa var. aggregatum) forma varios bulbos a partir de un solo disco basal y tiene mayor contenido de sólidos totales que aumentan su valor gastronómico y nutracéutico. Es un producto altamente valorado en el mercado europeo, estadounidense y sudamericano. En el Ecuador no se la registra como una variedad diferente a la cebolla roja. Sin embargo, la cebolla chalote es apetecida y utilizada dentro del sector gastronómi-co y aumenta el interés de su producción. El objetivo de este estudio fue estandarizar un protocolo de regeneración in vitro de plantas de chalote a partir de meristemas apicales. Se aisló meristemas apicales a partir de bulbos de chalote, se probó varios medios para la regeneración de plantas y la formación de bulbos. El porcentaje de regeneración de plantas más alto (68 %) se obtuvo con el medio: MS + 30g.L −1 sacarosa, 1.5g.L −1 benomyl + 1.1uM NAA + 8.9uM BAP, y de embulbamiento (77 %) con el medio: MS + 10uM ancymidol + 50g.L −1 sacarosa. Finalmente, el 50 % de plantas regeneradas a partir de meristemas fueron aclimatadas eficientemente. El protocolo establecido en esta investigación puede ser utilizado para mejorar la producción de bulbo-semilla y así promover el cultivo de cebolla chalote en el país.Palabras Clave. Allium cepa var. aggregatum, meristema apical, cultivo in vitro. IntroducciónAllium cepa var. aggregatum se caracteriza porque forma grupos de bulbos unidos por un mismo disco basal, mientras que la cebolla común (Allium cepa L.) solo forma un bulbo principal. Es originaria del centro y sudeste de Asia, y actualmente está distribuida en todo el mundo [1]. Posee un mayor contenido de sólidos (16-33 %) que la cebolla común (7-15 %), entre los que se menciona ácidos grasos, azúcares y comp...