Effects of exogenous strigolactone on growth, dry matter accumulation, and yield of tissue-cultured ginger

Ginger tissue culture seedlings can reduce the incidence of soil-borne diseases. However, they have several branches, small ginger bulbs, and slow seed recovery. Strigolactone can inhibit the growth of lateral buds, adjust plant types, and increase crop yield. This study used exogenous strigolactone to treat tissue-cultured ginger and assess its effects on growth, dry matter accumulation, and yield. The results showed that the number of branches and ginger bulbs per plant decreased significantly with the application of exogenous GR24 (Synthetic analog of strigolactone, rac-GR24), and higher concentrations led to a greater decrease. Plant height, stem diameter, root, rhizome, stem sheath, leaf and plant dry matter accumulation, average ginger bulb weight, and yield increased significantly, increasing initially and then decreasing with increasing concentration. Depending on the concentrations, exogenous strigolactone can inhibit the branching of tissue-cultured ginger, reduce the number of branches, increase plant height and stem diameter, optimize the aboveground plant type, increase dry matter accumulation and root-shoot ratio, decrease the number of ginger bulbs per plant, increase the average ginger ball weight, and increase yield. When the GR24 concentration was further increased, the number of branches, the plant height, stem diameter, dry matter accumulation, root shoot ratio, ginger bulbs per plant, average weight of ginger bulbs, and ginger yield decreased. Treatment with 7.5 um L-1 of exogenous GR24 could optimize the plant type of tissue-cultured ginger and increase yield.