In vitro morpho-regeneration, mass multiplication and bulb production in calla lily (Zantedeschia spp.) cultivars

This study explored in vitro morpho-regeneration responses and mass multiplication through long-term subculture in calla lily (Zantedeschia spp.) cv. Celesta, Gold Affair and Majestic Red. Significantly, the highest (91.40 %) and lowest (80.02 %) clean cultures were recorded in cv. Majestic Red and Gold Affair, respectively. In morphogenetic responses, the highest shoot numbers of 6.18, 4.45 and 5.24 (on 0.1 mg/L 2,4-D and 1.5 mg/L BAP) and the highest shoot lengths of 4.36, 3.99 and 3.87 were recorded in cv. Celesta, Gold Affair and Majestic Red, respectively, after a short span of 13–15 days of incubation. There was a reduction in the average number of shoots and shoot length in all cultivars during long-term subculture. All cultivars showed 100 % in vitro root induction. In hardening, survival varied with cultivars; the maximum (84.81 % and 66.54 %, respectively) survival in primary hardening and shade net was observed in cv. Majestic Red. The hardened plants were used for bulb production under a polyhouse. The highest ‘A’ grade bulbs were recovered from cv. Gold Affair (32.59 %). The ‘A’ and ‘B’ grade tubers of all cultivars have shown good flowering ability and the ‘C’ grade bulbs were weak in setting flowers. Overall, the study demonstrates efficient in vitro morpho-regeneration and sustained responses during long-term subculture for mass multiplication and bulb production in calla lily. This study presents a micropropagation system, which is simple, low-cost, viable and sustainable for large-scale production of healthy and quality calla lily plantlets as well as bulbs with flowering ability.