Natural interspecific hybrids between Acrocomia aculeata (Jacq.) Lodd. ex Mart. and A. totai Mart.: morphological evidence and agronomic traits

Abstract

We investigated naturally occurring interspecific hybrids between Acrocomia aculeata (Jacq.) Lodd. ex Mart. and A. totai Mart. populations, two important American oleaginous palm species with promising applications in energy, food and pharmaceutical industries. Prior to hybrid identification, a detailed morphological character study was conducted, utilizing biometric measurements of field plants and fruits from populations in convergent zones. Among the fruit measurements were mesocarp oil content and endosperm total protein. Significant morphological differences were observed between species, primarily in fruit epicarp, stipe, and leaves. Morphologically intermediate hybrids were identified, comprising 7% of the total individuals, within potential hybrid zones across three Brazilian states. Their agronomic traits were characterized and compared with those of the parental species. A. totai demonstrated greater prolificacy, resulting in higher productivity per plant of endosperm and endosperm total protein, despite lower individual fruit contents and smaller fruit size compared with A. aculeata. Hybrids exhibited similar productivity to A. totai but displayed character values from both parental species, without a clear pattern of inheritance. The study also delved into taxonomic aspects of the species and the interspecific hybridization implications to breeding programs research.