Effect of growth regulator treatment on bud sprouting of hardwood cutting in different ornametal plants

Abstract

The hardwood cuttings of Calliandra haematocephala, Cassia biflora, Pyrostegia venusta and Clerodendrum splendens were treated with different growth regulator concentrations and combinations (T1: NAA100 mg/l, T2: NAA 300 mg/l, T3: NAA 500 mg/l, T4: IBA100 mg/l, T5: IBA 300 mg/l, T6: IBA 500 mg/l, T7: NAA 100 mg/l + IBA 50 mg/l, T8: NAA 50 mg/l + IBA100 mg/l, T9: NAA 100 mg/l + IBA100 mg/l and T10: Control) for 12 h and planted either in polybags containing soil or in sand beds for callusing. The treatment of hardwood cuttings with T6: IBA (500 mg/l) for 12h resulted in the maximum (33.33%) mean per cent sprouting 60 days after direct planting in all the four genotypes. Among the genotypes, the per cent sprouting was significantly more in C haematocephala (47.33%), followed by P venusta (8.66%), C splendens (7.33%) and C biflora (7.33%), irrespective of the growth regulator treatment. The hard-wood cuttings, planted in the sand beds for callusing (2 weeks) exhibited the maximum (28.33%) mean per cent sprouting with T6: IBA (500 mg/l, 12h), 60 days after transplanting in the polybags in all the four genotypes. Among the geno-types, the per cent sprouting was significantly more in C haematocephala (48.67%), followed by P venusta (6.67%) and C splendens (2.67%), irrespective of the growth regulator treatment, however, the cuttings failed to exhibit sproutingin C biflora. The treatment of cutting with IBA 500 mg/l increase the sprouting percentage in C haematocephala, P venusta and C splendens which otherwise were difficult to propagate through cutting.