Phenotypic Variability of Liberoid Coffee (C. liberica and C. dewevrei) Across Sumatera and Javanese Landscapes: Foundational Insights for Coffee-based Agroforestry (Early View)

Abstract

This study reveals the phenotype diversity of Liberoid coffee in three agroforestry landscapes on two islands (Sumatra and Java) with contrasting soil conditions and microclimates, namely Betara (Jambi) in peatlands, and Wonosalam (Jombang) and Silo (Jember) in mineral soils. Principal Component Analysis (PCA) shows that primary variation is determined by the character of the fruit and seeds, while size and vegetative structure contribute as an additional source of diversity. The results of hierarchical clustering (AHC) show that the Jambi population is divided into three small groups with high heterogeneity, while most of the Javanese genotypes tend to be more homogeneous. The acidic conditions of the peat soil in Jambi encourage Liberoid coffee to adapt to the small but thick pulp fruit, while the soil in Java (pH tends to be neutral) stimulates vegetative growth more rapidly. These results confirm the urgency of preserving local coffee genetic resources for plant resilience in the face of various agroecological pressures, as well as being a foothold for the breeding of adaptive varieties based on agroforestry landscapes.