Analysis effect of shade level on the physiological and anatomical characteristics of hybrid Phalaenopsis orchid at the acclimatization stage

Abstract

Production of hybrid Phalaenopsis seedlings is generally applied by in vitro culture techniques. The final stage of in vitro culture is acclimatization. The acclimatization stage is crucial because the plantlets must adapt to the ex-vitro environment. Shade supports plantlet growth during the early stages of acclimatization. This study aims to determine the effect of shade level on the physiological and anatomical characteristics of the Phalaenopsis hybrid orchid at the acclimatization stage. The research used Phalaenopsis plantlet hybrid and shading level. Plantlets were shaded at 40%, 55%, and 70%. Parameters measured included: photosynthetic pigment content, number and area of leaves, number and length of roots, stomata density, size of stomata and fresh weight. This study used a completely randomized design with one factor and ten replications. Data were analyzed using the ANOVA test and LSD test at a significance level of 5% (p<0.05). The results showed the highest photosynthetic pigment content in the 55% shade, and there was a difference in the size of the stomatal guard cells between ex vitro and in vitro leaves at 40% shade. Shade level did not affect leaf growth, roots, fresh weight and stomata density. However, it affected photosynthetic pigment content and size of guard cells in the ex vitro leaves of Phalaenopsis hybrid orchids. The most optimal growth of the Phalaenopsis hybrid was at 55% shade.