Light intensity and rooting substrates are important for rooting growth and development of Zabelia tyaihyonii cuttings

Abstract

The Korean endemic species Zabelia tyaihyonii grows only in limited native areas of Chungcheongbuk-do and Gangwon-do provinces. This species is currently listed as an endangered taxon in the International Union for Conservation of Nature Red List, recommending conservation of its genetic resources. Few studies have addressed its asexual propagation. The effect of different light intensities (200, 300, and 400 μmol m−2 s−1 PPFD) and rooting substrates (phenolic foam, decomposed granite soil, and pearlite) on growth and development of Z. tyaihyonii cuttings was evaluated. The rooting percentage was the highest in phenolic foam with 300 μmol m−2 s−1 PPFD, but new shoots were formed in decomposed granite soil with 400 μmol m−2 s−1 PPFD, with positive growth and development compared with that in other planting conditions concerning rooting percentage, root length, number of roots, and fresh and dry mass of the shoots and roots. Thus, phenolic foam with 300 μmol m−2 s−1 PPFD can support good growth when propagating Z. tyaihyonii from cuttings, but decomposed granite soil with 400 μmol m−2 s−1 PPFD may be a more suitable choice for their efficient growth and development.