Genotype dependent influence of phytohormone combination and subculturing on micropropagation of sugarcane varieties

Abstract

Eight varieties of sugarcane, viz. Co.89003, Co.91010, Co.96258, Co.97017, Co.P84211, Co.P84212, Co.P90223, and Co.S767, were successfully established and micropropagated using shoots tips as explants. Four combinations of phytohormone, having NAA (1 mg/L) at fixed conc. and two cytokinins, i.e. BAP and Kn, at varying conc., were used; these were designated as A₁ (1 mg/L BAP + 2 mg/L Kn); A₂ (1 mg/L BAP + 3 mg/L Kn); A₃ (3 mg/L BAP + 2 mg/L Kn) and A₄ (6 mg/L BAP and 1 mg/L Kn). All the varieties were successively sub cultured up to 8^th passage. Maximum percentage of explant establishment (80-100%) was observed for all the varieties, except Co.P.84212 and Co.P. 90223 (50-60%). No influence of genotype was found on the days required for side bud induction, average length of shoots from side bud, and number of days for multiple shoots when explants were placed in various phytohormone combinations. However, individual varieties showed preference for higher or lower conc. of cytokinins, i.e. growth of shoots in varieties Co.89003, Co.91010, Co.96258, Co.97017, Co.P84212 and Co.P.90223 was better in A₁ and A₂ hormone profile, while that of Co.91010 and Co.S767 in A₃ and A₄ hormone profile.