Morphogenetic responses of stem explants and axillary shooting in node segments from adult trees of Pittosporum pentandrum (Blco.) Merr

• Published in: Asia life sciences Vol. 11; no. 1
• Main Authors: Edmiston, M.P.F. (De La Salle Univ., 2401 Taft Ave., Manila (Philippines)) Halos, S.C, Rivero, G.C
• Format: Journal Article
• Language: English
• Published: 01.01.2002
• Subjects: CULTURE MEDIA; ESPECE; ESPECIES; EXPLANT; EXPLANTES; EXPLANTS; MEDIO DE CULTIVO; MICROPROPAGACION; MICROPROPAGATION; MILIEU DE CULTURE; MORFOGENESIS; MORPHOGENESE; MORPHOGENESIS; PITTOSPORUM; SPECIES; STEMS; TALLOS; TIGE
• ISSN: 0117-3375

Pittosporum pentandrum (Pittosporaceae) is a medicinal and a hydrocarbon-producing plant. Its threatened status is due to the plant's difficulty in fruit setting and wide-scale habitat destruction and deforestation. This reports the first successful micropropagation of the plant by formation of axillary shoots in node segments of shoots obtained from adult trees. It also reports on the various morphogenetic responses of stem explants in three levels each of NAA and 2,4-D added singly or in combination to Murashige and Skoog Medium with 40.00 microM BA. Stem explants formed profuse callus and callus-mediated roots when high doses of NAA and 2,4-D were added alone or in combination and these occurred best between 100 to 140 days after inoculation. Axillary shoots in node segments emerged as early as five days after inoculation and ranged from 55.00 to 66.00% in treatments with BA alone and when BA and 2,4-D were added in low doses of 0.67 microM and 0.57 microM, respectively. The average shooting rate for each node segment per shooting cycle ranged from 1.35 to 2.06 under these treatments. Shoots excised 61 to 80 days after emergence had up to 100% rooting in Gresshoff and Doy's medium + 0.06 microM IAA after 20 d. They had a better rooting response than those excised 40 to 60 days after emergence