Effects of foliar-applied homobrassinolide on the ex vitro acclimatization of Guarianthe skinneri (Bateman) Dressler & W.E.Higgins

Objective: To identify the influence of foliar application of homobrassinolide at various doses and frequencies on the growth and ex vitro acclimatization of Guarianthe skinneri (Bateman) Dressler & W.E.Higgins Design/methodology/approach: G. skinneri seeds were germinated in vitro on Yasuda medium. Once the seedlings developed roots, leaves and reached a height of 2 cm, they were transferred to the nursery for ex vitro acclimatization. Coconut fiber was used as a substrate in 10 oz beakers. Hbr-based treatments were generated with three doses of Hbr (2, 4 and 6 mgL-1) and three application frequencies (every 7, 14 and 21 days), plus a control with 10 replicates in a completely randomized design. he following variables were evaluated at 28, 56, 70, 77, and 91 days: plant height, number of green and dry leaves, and number of dead plants. Results: Foliar application frequencies and concentrations of Hbr induce differential growth and survival of G. skinneri. Applying Hbr more frequently at higher concentrations improves G. skinneri survival in the nursery. Limitations on study/implications: The results may vary under different environmental conditions during the acclimatization of G. skinneri. Findings/conclusions: Foliar application of Hbr induced greater growth in G. skinneri, particularly in terms of plant height. More frequent applications and higher concentrations of Hbr improved the acclimatization and survival of G. skinneri in nursery conditions. Different concentrations and application intervals of foliar Hbr resulted in distinct effects on the growth and survival of G. skinneri.