Effect of Rooting Hormone on Macro-proliferation of Different Bamboo Species

Bamboo is an ecologically and economically important resource with significant potential for supporting livelihoods, enhancing carbon sequestration, and promoting sustainable land management. However, large-scale cultivation is constrained by irregular flowering, limited seed production because most of the species do not produce seed every year, and short seed viability, which limit natural regeneration. Therefore, the development of efficient vegetative propagation techniques is essential to ensure a continuous supply of quality planting material. Therefore, the present study was conducted during February to June 2024 at the Bamboo Resource Centre, College of Forestry, Navsari Agricultural University, Navsari, Gujarat, to evaluate the effect of different auxin concentrations on macro-proliferation of different bamboo. The experiment was laid out in a factorial completely randomized design using one-year-old seedlings of Bambusa nutans, Bambusa tulda and Bambusa polymorpha, subjected to seven auxin treatments including control, IBA (indole-3-butyric acid) (100 and 200 ppm), NAA (naphthalene acetic acid) (100 and 200 ppm) and their combinations. Observations on sprouting, growth, rooting, survival and multiplication rate were recorded at 120 days after treatment. Results revealed that Bambusa nutans exhibited superior growth performance and multiplication rate, whereas Bambusa polymorpha performed better in root development and survival. The results revealed that the across treatments, G₁ (control) consistently recorded significantly higher values for all parameters, among the auxin-treated propagules, G₂ (IBA 100 ppm) showed comparatively better performance and remained closer to the control. However, higher concentrations of auxins and their combinations, particularly G₄ (IBA 100 ppm + NAA 200 ppm), G₅ (IBA 200 ppm + NAA 100 ppm), G₃ (IBA 200 ppm), and G₇ (NAA 200 ppm), resulted in a significant reduction in all parameters. Overall, almost all parameters responded positively to the control, while the application of auxins adversely affected the performance of macro-proliferated propagules. The findings demonstrate that exogenous auxin application is not required for macro-proliferation of bamboo under nursery conditions, providing a cost-effective and ecologically sustainable approach for large-scale bamboo propagation and ecological restoration.