Phenotypic characterization of Mexican orchid Laelia Autumnalis

Laelia autumnalis, an endemic species of Mexico is quite attractive because of its flowers’ beauty, being a threatened species due to the serious disturbance of its habitat and the excessive gathering by humans. The purpose of this study was to phenotypically characterize 85 accessions of L. autumnalis from pine-oak forests in Michoacán, Mexico. Fifty nine morphological variables were recorded and, an analysis of variance, principal component (PC) and cluster analysis (CA) were made as well. The number of pseudobulbs, curvature of the ovary and the number of leaves were the measured variables with the highest variability. The first three PCs concentrated 63.63% of the variability; PC1 represented 35.02% of the total variability, as determined by the length and width of the column. PC2 contributed 15.82% to the variability, as determined by the length of the pseudobulb, and the length of leaf 1. PC3 contributed 12.80% to the variability as influenced by the diameter of the pseudobulb and the length of the bracteole. Two groups were identified from CA. Group I, with 58 accessions, showing large structures with 79.67 mm in average length of pseudobulbs. The inflorescences are long with three flowers on average, sepals and petals with 55.33 and 50.42 mm in length, respectively; the flowers showed intense magenta shades in the middle lobe (N80A) and medium magenta shades at the apex of the column (N81B). Group II comprised of 27 accessions with smaller structures than those from Group I; the pseudobulbs averaged 62.64 mm in length. The inflorescences are smaller (44.76 cm long), the flowers with medium magenta shades in the middle lobe (N81B) and, soft magenta shades at the apex of the column (N78B). These results provide relevant data on the morphological variability of this species and on its potential for ornamental use, and for conservation.