Phenotypic characterization and genetic diversity of macauba (Acrocomia aculeata) accessions based on oil attributes and fruit biometrics

Macauba is a Brazilian native palm whose fruits have a great economic potential, due to the presence of oil in the pulp and kernel, which can be used by biofuel, cosmetic and food companies. The study of its genetic variability paves the way for the pre-breeding of the palm tree. In this context, the present work aimed to evaluate the genetic variability in macauba genotypes from different Brazilian locations. For such, 50 accessions were evaluated for pulp oil attributes and productivity traits in three populations (Pop1, Pop2, Pop3). The pulp oil attributes were the fatty acid composition, pulp oil color and carotenoid content. The productivity traits were the fruit diameter and the dry mass of the fruit weight, husk, pulp, endosperm and kernel; as well as pulp oil content. The results revealed that Pop1 presented the smallest fruits and the highest content of carotenoids, while Pop2 and Pop3 presented the largest fruits and lowest carotenoid content. The highest oil content was observed in Pop3. Fatty acid analyses revealed the presence of oleic (C18:1), palmitic (C16:0), linoleic (C18:2), palmitoleic (C16:1), stearic (C18:0), and linolenic (C18:3) acids in macauba pulp oil. The carotenoid content ranged from 27.09 to 2682.87 mu g/g. The color of the macauba pulp oil was diverse among the different genotypes, ranging from red to green. Their genetic diversity demonstrated that the accessions clustered according to their geographic origin. Our results revealed that macauba had high variability for the traits evaluated and potential to be genetically improved.