Anatomical comparison of two Grammatophyllum spp. (Orchidaceae) species and their specific ecological adaptation

The genus Grammatophyllum (Orchidaceae) has two sections with a very different habitus. The Grammatophyllum from section “Grammatophyllum” has a long cylindrical pseudobulb with linear leaves, while the Grammatophyllum section “Gabertia” has a shorter pseudobulb with a larger diameter and broader lanceolate shaped leaves. The study is aimed to compare the anatomical characters of leaf and root between G. speciosum (representation of “Pattonia” section) and G. scriptum (representation of “Gabertia” section). Leaf and root sections were obtained using the mini-microtome with liquid preservation method in 10 replications. Data were analyzed statistically using a t-test at 5% significance. The results showed significant differences between the two species in the leaf's primary vascular bundle area, velamen area, number of velamen layers, root's cortex area, and stele area. Future research with more organs and parameters being explored and experimental research regarding its anatomical response to drought is suggested.