Agro-Morphological Traits, Proximate Composition, and Phenotypic Plasticity of Coffea arabica in Contrasting and Very Close Environments in Northern Peru

Coffee is one of Peru’s most important agricultural commodities, and its productivity is highly influenced by environmental variability. This study aimed to evaluate agro-morphological traits, proximate bean composition, and the phenotypic plasticity index (PPI) of Coffea arabica (Catimor variety) cultivated in three neighboring provinces of Piura: Ayabaca, Huancabamba, and Morropón. Unlike previous studies that broadly compare distant regions, this research focuses on geographically close yet climatically contrasting environments, providing new insight into how microclimatic and edaphic variability shape both morphological and chemical traits. A total of 300 plants were sampled, and 12 morphological descriptors were recorded alongside proximate composition analyses of moisture, crude protein, fiber, ash, fat, and carbohydrates. Multivariate approaches, including cluster analysis, multiple correspondence analysis, and Pearson correlations, were applied to determine groupings and trait associations. Results indicated that 12 morphological variables consistently reflected species-specific descriptors, forming two statistical groups, with Morropón showing the greatest homogeneity. Significant differences (p ≤ 0.05) were observed in the proximate composition of most variables, except for crude fiber and carbohydrates. Morropón beans showed the highest fat and moisture values, while Huancabamba had elevated protein and ash levels. Morphological traits exhibited higher plasticity (PPI = 0.70) compared with proximate traits (PPI = 0.21). These findings reveal that even within short spatial distances, coffee plants exhibit marked phenotypic differentiation driven by local environmental factors, offering a novel, fine-scale perspective on trait variability relevant to breeding and adaptation studies under changing climatic conditions.