Plant Regeneration from the Mass of Shoot Primordia in Rhododendron pentaphyllum Maxim. var. nikoense Komatsu

Abstract

A mass of shoot primordia were induced effectively from the shoot apex of Rhododendron pentaphyllum Maxim. var. Komatsu on WP media containing 30μM 2iP+IAA (10, 30, 100μM). Of the shoot primordia obtained, those cultured on WP medium supplemented with 10μM IAA and 30μM 2iP showed the most active proliferation, being 2-4 times in size, after one month of subculture. When shoot primordia obtained were transferred onto the differentiation media, multiple shoots were formed on WP media containing zeatin (1, 10μM) or 0.1μM CPPU after one month of culture, irrespective of the presence of IAA. The multiple shoots induced on the medium containing 10μM IAA and 10μM zeatin showed active elongation growth. Rooting from the multiple shoots subcultured on the same fresh medium occurred two months after the shoot differentiation.