Fruit and seed characterization of wild populations of a traditional Andean crop: Solanum betaceum Cav. (Solanaceae) in the Argentinian Yungas

Chilto ( Solanum betaceum Cav.) is a traditional Andean crop, appreciated for its high nutritional and commercial value. Despite it is cultivated in many countries, the information about the diversity, and conservation of wild populations is still missing. The objectives of this work were to characterize wild populations of the species in northwestern Argentina, regarding the morphological traits of fruits and seeds, to decompose the observed phenotypic variability, and to look for associations between morphological and geographical distances. Fruit weight, length and equatorial diameter, pericarp thickness, pH, total soluble solids were measured in fruits from nine populations, and then a intra and inter population comparison was performed. The phenotypic variance was decomposed by a nested ANOVA. The associations between geographical and morphological distances were assessed by the Mantel test. A wide variability was found in fruit weight, pericarp thickness, and fruit length (24, 19 and 13% coefficient of variation, respectively). Nested ANOVA revealed significant differences in all fruit and seed traits among and within populations ( p < 0.001). Fruit weight and length were the traits with the highest total phenotypic variation. The main contribution to phenotypic variance was made by the environmental variance, which includes differences in temperature, precipitation, humidity but also to the experimental error. There were no associations between morphological and geographical distances; although, neighboring populations showed greater similarity. Chilto wild populations have many important characteristics with high potential as a productive regional alternative and as asource for improvement.