Augmenting in vitro shoot multiplication by vipul (triacontanol) and adventitious rhizogenesis by rice bran extract in Dendrocalamus strictus.

Like other bamboo species, Dendrocalamus strictus flowers gregariously after a prolonged intermast period of 48 years and constitutes an ideal material for in vitro clonal propagation. In this study, MS liquid medium containing 0.5, 1.0 and 2.0 mL/L vipul (Godrej Agrovet, Ltd., Sachin, India), a commercial formulation of triacontanol, with or without BA (3.0 mg/L) was tested for in vitro shoot multiplication and 1.0, 2.5 and 5.0 mL/L of 20% (w/v) alcoholic/aqueous rice bran extract (alone or in combination) with NAA (3 mg/L) used for in vitro adventitious rhizogenesis in single node culture derived shoots of Dendrocalamus strictus.. After a multiplication cycle for 4-5 week, vipul (0.5 mL/L) with BA (3.0 mg/L) in the culture medium induced 4.59 fold shoot multiplication rate whereas application of BA and vipul alone had corresponding values of 3.29 and 0.53 fold respectively. Maximum vipul concentration (2 mL/L) with BA (3 mg/L) exhibited shoot multiplication higher than (or equal to) that of BA alone. Maximum in vitro rooting percentage (55.66%) was obtained on half MS medium enriched with alcoholic rice bran extract (2.5 mL/L) and NAA (3 mg/L). This is the first investigation reporting amelioration of in vitro shoot multiplication rate by triacontanol and rooting percentage by rice bran extract in explants from mature bamboo culms. The protocol is economical and rapid for in vitro clonal propagation of Dendrocalamus strictus.

IAA synergism and vitamin B1 antagonism with calcium for induction and growth of adventitious roots in branch cuttings of Dalbergia sissoo Roxb.

IAA induced adventitious roots in branch cuttings of D. sissoo, whereas vit. B1 promoted growth of these roots. A strong IAA synergism and vit. B1 antagonism with calcium was observed in induction and growth of adventitious roots. Treatments with IAA (571 microM) and calcium (134 microM) proved to be an ideal combination, exhibiting 87% rooting and 0.87 R/S ratio in branch cuttings, coupled with an increase of root length, root number, root fresh weight and root dry weight as compared to control.