Ecological Correspondence Between Morphological Variation and Germplasm Movement Zones of Cedrela odorata L. in Southeastern Mexico

This study analyzed seven foliar traits of Cedrela odorata L. (Meliaceae) in 87 individuals across three germplasm movement zones in Tabasco, Mexico (VIII: humid; XIV: intermediate; XXI: dry) to assess differentiation and climatic relationships. Leaf length, area, petiolule length, leaflet number, rachis length, width, and stomatal density were measured. Univariate tests, canonical correlation analysis, redundancy analysis, and a relative phenotypic plasticity index were applied. Significant morphological differentiation was found: zone XIV exhibited the largest leaves and longest rachises, zone VIII the highest stomatal density, and zone XXI smaller, more subdivided leaves. The first canonical axis (r = 0.846, p < 0.001) associated long and wide leaves with warm, humid conditions, while the second (r = 0.810, p < 0.001) linked stomatal density and width to temperature minimum. Climate explained 55.7% of morphological variation, primarily through water and temperature gradients. High plasticity in leaf area, rachis length, and stomatal density suggests adaptive flexibility, yet consistent inter-zonal differences indicate local adaptation. These results demonstrate a strong correspondence with Tabasco’s germplasm movement zones and providing morphological evidence to support reforestation and germplasm management strategies under variable climatic conditions.