Objective A concise collection of Phalaenopsis germplasms based on their phenotypic traits was preliminarily assembled to facilitate conservation and utilization of the natural resource.

Methods Two hundred and ten Phalaenopsis germplasms encompassing 32 phenotypes, including 13 qualitative and 19 quantitative traits, were included in this study. The random, preferred, and deviation sampling methods, the Euclidean and Mahalanobis genetic distances, the 20%, 25%, and 30% sampling ratios as well as the single, complete, median, centroid, unweighted, weighted, flexible, and ward clustering methods were employed in comparison to optimize the selection process. The information obtained was scrutinized with evaluations on the mean difference percentage (MD), variance difference percentage (VD), range coincidence rate (CR), and variation coefficient change rate (VR). It was further verified by the mean and extreme comparative analyses and principal component analysis to arrive at a concise and representative collection of the germplasms.

Results The germplasms for the collection were eventually gathered by means of the preferred sampling at the Euclidean distance and 25% sampling ratio with the complete clustering. Out of the 210 germplasms, 52 selected cultivars were deemed to statistically represent the genetic diversity of the current collection with all the principal components on phenotypic traits preserved without redundancy.

Conclusion  The collection of Phalaenopsis germplasms assembled by this study was concise and representative of the resource presently in stock. It covered all key phenotypes needed to be preserved for future studies and applications.