Highland papayas in southern Ecuador: need for conservation actions

Southern Ecuador is considered to be a centre of biodiversity of the so-called highland papayas. In Southern Ecuador, this group, which comprises lesser-known Andean Caricaceae that grow, mostly in the wild, above 1000 masl, consists of Carica pubescens (A. DC.) Solms-Laub., C. stipulata Badillo, C. × heilbornii Badillo, C. candicans A. Gray, C. weberbaueri Harms., C. parviflora (A. DC.) Solms-Laub., C. microcarpa Jacq, C. monoica Desf. and the new endemic species C. palandensis Badillo, Van den Eynden & Van Damme. At this moment only the natural hybrid C. × heilbornii nm. pentagona Badillo, commercially known as babaco, is getting attention on the continuously expanding subtropical fruit market. Natural hybridisation and presence of accessions of which taxonomical position (at the species level) remains unclear, combined with a limited number of botanical studies, suggest that the taxonomy of the Caricaceae in Southern Ecuador is still not completely explained. Nevertheless, local collections and characterisation studies show that, from an agronomical point of view, these highland papayas show a big potential for the future. Organoleptic characteristics of some accessions and species are very promising, especially for use as juices and marmalades. Making use of natural or artificial hybridisation can even expand this potential. Analyses of the activity of the proteolytic enzyme complex (papain) of these local accessions and species showed that the latex of the unripe fruit possessed up to 15 times more activity than papaya (Carica papaya L.) cultivars selected and grown for their high enzyme activity. This potential, which needs further detailed study, is increasingly under threat as population is increasing, putting pressure on fallow and forest land and concentrating agricultural systems on food and cash crops, consequently neglecting little known native fruit crops and reducing the natural vegetation in which they occur. A survey on local knowledge of these highland papayas showed that younger people have significantly less knowledge on them than older people proving the urgent need for further studies and conservation strategies.