Comparison, determination and optimizing the conditions required for rhizome and shoot formation, and flowering of in vitro cultured calla explants

• Published in: Scientia horticulturae 2004-09, Vol.101 (3), p.305-313
• Main Author: Ebrahim, Mohsen K.H
• Format: Article
• Language: English
• Subjects: Acclimatization; Agronomy. Soil science and plant productions; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Gelation; General agronomy. Plant production; Growth regulators; Hardening-off; Sucrose; Vegetative propagation. Micropropagation; Vegetative propagation. Sowing and planting. Harvesting; Zantedeschia aethiopica
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/j.scienta.2003.11.002

Aseptic cultures of calla were established from rhizome-bud explants which were surface-sterilized in 4% NaOCl solution for 5 min. Cultures were initiated on a medium containing Murashige and Skoog (MS)-salts, benzyladenine ( 2 mg l −1=8.9 μM) and agar (5 g l −1). Explants were transferred at 4-week intervals, on MS basal medium supplemented with kinetin ( 5 mg l − 1=23.2 μM), until the onset of proliferation (ca. 2 months). Thereafter, four subcultures were made in liquid media similar to the latter one. Shoots produced developed rhizomes and/or rooted plantlets depending on the culture conditions. Rhizomes were successfully formed on MS-basal media containing sucrose (70 g l −1) and Na-dikegulac ( 1.69 μM=0.5 mg l −1). They were germinated and grown in greenhouse to develop flowering potplants. The highest multiplication rate and lowest hyperhydricity were achieved, in a medium containing 2-isopentenyladenine ( 12.3 μM=2.5 mg l −1), by culturing the explants at 4-week intervals in two ways: (1) on solid media (6 g agar l −1) or (2) alternatively in liquid (no agar) and solid (6 g agar l −1) media. Adding alpha-naphthalene acetic acid ( 1 mg l −1=5.4 μM) to a solid MS-basal medium containing MS salts at a half strength supported the fastest growth and development of roots. Hardening-off and acclimatizing the rooted plantlets led to development of flowering potplants served for producing white attractive cutflowers.