High frequency multiple shoot induction and in vitro regeneration of mulberry (Morus indica L. cv. S-1635)

A simple, high frequency and reproducible protocol for multiple shoot induction and in vitro regeneration from nodal explants for commercially exploited mulberry cultivar S-1635 have been developed. Explants collected from the field grown plants were cultured on MS medium supplemented with different concentration/combination(s) of phytohormones. Presence of TDZ (9.08μM) in the shoot induction medium showed pronounced increment on the number of multiple shoots (6.22±0.70) produced. Rapid bud breaking with respect to duration was achieved in MS media supplemented with BAP (4.44 μM) and the maximum mean shoot length (6.02 ±0.6 cm) was obtained with combination of BAP (4.44 μM) and GA (1.44 μM). Highest number of roots (17.0±1.67 no. plantlet-1) with maximum mean length of root (6.3cm) was inducted after 30 days of inoculation in IBA (9.8 μM) fortified half MS media. The regenerated micro plantlets after 60 days of indoor acclimatization were successfully established in the soil under field conditions without visible morphological variation. The protocol may provide a suitable platform to generate clones of triploid commercial mulberry cultivar S1635 round the year in a significantly shorter period with less involvement of land mass and manpower and for utilization in advanced breeding program.