Puya santossi in vitro propagation

Puya santossi (L) is an endemic threatened shrub from the high Andean region. Conservation procedures must thus be established for this important germplasm species’ conservation. This study evaluated the in vitro adaptation of this species with Benlate and nine sodium hypochlorite treatments and the effect of five growth regulators on the morphogenetic development of shoots, meristems and leaves. The base medium used was MS enriched with the following growth regulators: indol butyric acid (IBA) and benzylaminopurine (BAP) (0.0, 0.5, 1.0 and 1.5 mg/L) in meristem culture; α-naphthaleneacetic acid (NAA) (0.0, 1.0, 2.0 and 3.0 mg/L) in the rooting of buds regenerated in vitro; 2, 4-dichlorophenoxy acetic acid and Kinetin (0.0, 1.0, 3.0 and 5.0 mg/l) in leaves. It was observed that treatment 5 (1% NaOCl, 10 min) was the most successful in contamination control. The meristem was the most appropriate explant for Puya santossi micropropagation, allowing mass proliferation of adventitious buds when they were grown on MS media enriched with 1.5 mg/L BAP. Buds from the meristem culture were rooted with 3.0 mg/L NAA. This protocol represents a conservation model for endangered species and led to propagating Puya santossi. This investigation revealed that morphogenetic leaf explants were inhibited by the presence of a group of chlorophycea algae which were found to be symbiotically associated with P. santossi. Key words: Puya santossi; micropropagation; endangered plant; growth regulators