Biología reproductiva de tres especies de Polylepis (P. neglecta, P. incarum y P. pacensis), con énfasis en su comportamiento germinativo

Abstract

Reproductive biology of three Polylepis species (P. neglecta, P. incarum and P. pacensis), with emphasis on their germinative behavior. With the purpose of contributing to the knowledge on the sexual reproduction of native species of Bolivia of the genus Polylepis (P. neglecta, P. incarum and P. pacensis), as a base for the production of seedlings destined for reforestation, different germination studies were developed. To obtain seeds, potential seed trees were identified both in natural populations (P. pacensis and P. incarum) as well as in green areas of the Municipality of La Paz (P. neglecta). At the same time a fruit an seed morpho anatomical characterization by species was developed. In relation to the physical quality, depending on the sample, 100 g of seeds per species, a high degree of impurities was found, which made it difficult to obtain pure seed for sowing. The percentage of humidity of seeds was low: 10% in P. incarum, 8% in P. pacensis and 6% in P. neglecta; as in consequence, they could be considered as orthodox seeds (i.e., can be stored for a long time without losing the germinative power). A germination of 10% (P. neglecta), 8% (P. pacensis) and 2% (P. incarum) was obtained. On the other hand, the germinative response of seeds of these Polylepis species under greenhouse conditions showed the highest percentage of germination (19%) in the substrate sand+peat 1:1. The species with the highest percentage of germination was P. neglecta (10 to 15%), while P. pacensis and P. incarum showed 8 and 2%, respectively. Despite the low germination percentage known for the genus Polylepis, having a good amount of seeds and adequate conditions for their development (i.e., humidity, substrate, temperature) makes possible to spread these species massively under greenhouse conditions, with optimal results in terms of quantity and quality of plants.https://doi.org/10.25260/EA.18.28.1.1.703