Morphological Characterization of Hybrids Derived from the Pollination of Hoya deleoniorum

A number of Hoya cultivars have emerged as significant horticultural plants, considering the broad range of ornamental traits these plants possess. Market demand has consistently been driven by distinctive foliage and flower attributes. In this study, two first-generation offspring from the pollination of Hoya deleoniorum as a seed parent were selected, and their characteristics were examined. Using 36 leaf and floral traits, phenetic investigation and cluster analysis were performed on the hybrids (GTX-021, GTX-067) and parent species (H. deleoniorum, H. peninsularis, H. subquintuplinervis). Polymorphism was observed among 14 of the 24 qualitative characters evaluated, whereas significant differences (p<0.05) were observed for 11 of the 12 analyzed quantitative characters. A dendrogram based on morphometric measures, expressed through Euclidean similarity coefficients using the UPGMA method, separated the seed parent from other genotypes while grouping the pollen parent with its offspring. Due to its morphological intermediateness to its parents, the F1 GTX-021 was selected from the resultant population of H. deleoniorum x H. peninsularis. The morphometric measurements of GTX-021 reveal a close resemblance to its pollen parent. The F1 GTX-067, on the other hand, is more similar to its pollen parent, H. subquintuplinervis, in terms of qualitative morphological traits, but significantly smaller in terms of leaf and corona measurements. The distinct morphological traits of the F1 plants documented in this study enhance the ornamental value of the genus. Additionally, it is expected that these hybrid plants will improve genetic diversity, which will be essential to subsequent Hoya breeding initiatives.