The effect of concentration and length of soaking time shallot extract to the growth of orchid (Dendrobium sp.) at the acclimatization stage

Dendrobium sp. is a famous type of orchid with the various terms of colors and shapes, flexible flower stalks, and a relatively long freshness level. The application of plant growth regulator (PGR) in orchid cultivation has been widely report to solve a long juvenile period. Especially in acclimatization stage, as we believed is critical stage of in vitro propagation, the efforts to accelerate the growth process is needed. This study aims to determine the effect of organic matters, the shallot extract in several concentrations and length of soaking time as PGR to the growth of orchid Dendrobium sp. at the acclimatization stage. This research was arranged factorially (4x3) using a randomized block design (RAK) at Floriculture. The first factor is four level of shallot extract in concentrations (0 g L−1, 400 g L−1, 600 g L−1, and 800 g L−1), and the second factor is three level length of soaking times (20 minutes, 30 minutes, and 40 minutes). The data were tested with analysis of variance and LSD test at the 5% level. The result showed that shallot extract increased the plant height, number of leaves, and length of leaves. The shallot extract treatment with 20 and 30 minutes of soaking time increased plant weight and number of roots. The combination of shallot extract at 400 g L−1 with 20 minutes soaking time showed a higher plant height, number of leaves, plant weight, and the number of roots than other treatment combinations.