Establishment of callus cultures and plant regeneration in strawberry (Fragaria x ananassa duch.) cv. chandler

Leaf, petiole and stipule explants of strawberry were treated for the establishment of callus cultures, but callus initiation could be obtained only in leaf and petiole explants. The maximum callus induction percentage (88.89%) was recorded in MS medium containing 0.5 mg/l BAP + 0.75 mg/1 NAA. Callus obtained from both leaf and petiole explants was light green, friable and compact. Regeneration was difficult to achieve. A total of 93 different combinations of growth regulators were tried. Callus differentiated into shoots after transfer to MS medium supplemented with 2 mg/1 BAP+ 0.25 mg/l NAA + 0.5 mg/l kinetin. The regeneration percentage was higher in petiolar callus (83.33%) as comparedwith the leaf-derived callus (81.67%). Well developed shoots in both leaf and petiolar calli obtained after 50–55 days were transferred to multiplication medium containing 0.5 mg/l BAP + 0.5 mg/l kinetin and 1.0 mg/l GA₃. Rooting was done in MS half strength + 1.0 mg/l IBA and 0.2 mg/l activated charcoal. Once the root system was fully developed, the plantlets after washing were kept in 0.5% bavistin for 15–20 minutes and were planted in pre-sterilised mixture of soil: FYM (1:1) filled to two third of the capacity and rest filled with sterilised sand. Plantlets were hardened and then transferred to field.