Seed germination of Corryocactus melanotrichus (K. Schum.) Britton & Rose (Cactaceae): an endemic columnar cactus of the Bolivian Andes

Abstract

It has been documented that most columnar cactus species have anatomical features for vertebrate dispersal (Soriano & Ruiz 2002, Godinez-Alvarez et al. 2003). Frugivorous birds are known consumers of cactus fruits in different semi-arid zones of the Neotropics (Soriano et al. 1999, Soriano & Ruiz 2002). Although the recruitment pattern of columnar cacti depends strongly on seed dispersal by animals, our knowledge of the effect of seed ingestion by dispersers on the germination is still unknown for most Andean columnar cactus species. Different studies have indicated that seed germination in some cacti increases when the seeds are ingested by bats and birds (Olin et al. 1989, Naranjo et al. 2003), when soaked in acid solutions or when imbibed for different periods (McDonough 1964, Godinez-Alvarez & Valiente-Banuet 1998). These results suggest that seed treatments provided by dispersers may play an important role in the establishment phase of cacti (Godinez-Alvarez et al. 2003). Dormancy in plants is a process