Phenotypic analysis of the edible fruits of Lardizabala biternata, an endemic and monotypic vine from the Chilean biodiversity hotspot in South America.

IntroductionLardizabala biternata is a vine endemic to Chile, distributed between 32{degrees}S and 40{degrees}S. Its sweet edible fruits have historically been harvested by hand from the wild as there are no productive systems for this vine. Herein, we conducted the first phenotypic analysis of L. biternata fruits, which includes qualitative and quantitative analyses of morphological and morphometric traits. This phenotypic analysis is the baseline for the development of production systems that could reduce anthropogenic pressure on wild populations and favour the ex-situ conservation of this vine. Materials and methodsWe collected 282 fruits from two geographically distant populations during four fruiting seasons. In all of them we recorded 14 morphological attributes, including total weight, length, width, height, diameter, volume, edible pulp content, seed number weight and individual seed weight. We investigated morphometric differences between populations and seasons by analysis of variance (ANOVAs), phenotypic correlations by regressions and associations between traits by principal component analysis (PCA). ResultsOn overage, fruits weighed 20.8 g (3.0 - 44.6 g) and measured 54 mm in length (20.1 - 83.4 mm) and 23.7 mm in diameter. Edible pulp contributed around 44.4% of total fruit weight. Observed traits displayed significant variations between seasons and among traits (length vs width vs height). Fruit weight showed a high correlation with edible pulp weight, fruit length, seed weight, seed number, and others. Discussion and conclusionsOur study represents the first phenotypic analysis of the fruits of this wild, endemic, and rare plant. We comprehensively describe the morphological and morphometric characteristics of its fruits. The characteristics of L. biternata fruits show significant morphometric variation between populations and seasons. However, the edible pulp consistently remains the main component of the fresh fruit weight. Like other domesticated members of the Lardizabalaceae, the fruits of this wild plant have the potential for cultivation through the development of sustainable production systems. The information we provide serves as a baseline for the development of such systems through selection and genetic improvement of the plant.