Abstract: Broccoli (Brassica oleracea) is an important vegetable crop grown in the highlands of Indonesia. Cotyledon is used as a source of explants for in vitro shoot regeneration. The objective of this research was to examine the influence of the growth regulators 6-benzyl amino purine (BAP) and naphthalene acetic acid (NAA) on shoot formation in these cultivars. The shoot regeneration system of cotyledoned explants can be useful as a tool for synthetic seed formation. Cotyledon explants excised from 14-day-old in vitro germinated seedlings were placed on shoot induction medium containing basal salts of Murashige and Skoog (MS) and various concentrations of BAP and NAA. The highest percentage of cotyledon explant producing shoot (90 %) and the highest mean number of shoots produced each bottle of culture (1.15) were obtained on 1 mg/l BAP. Therefore, 2 mg/l BAP with 0.5 mg/l NAA are the recommended combinations for shoot regeneration from cotyledonary explants.
Keywords: Broccoli, 6-benzyl amino purine, naphthalene acetic acid, in vitro, shoot formation, cotyledon