Germination and Early Growth of Acacia nubica Benth. In vitro

Acacia nubica is well-adapted to harsh conditions and offers valued socio-economic and environmental benefits. This research studied seed germination and seedling growth of A. nubica in vitro in response to the application of different concentrations of sodium hypochlorite, sucrose, and Murashige and Skoog (MS) medium. The synchrony, percentage, and rate of germination of A. nubica seed were studied. Seedling development was assessed by measuring the shoot, root, and number of nodes. Sodium hypochlorite at 10% produced the maximum germination percentage, while 5% induced a faster and more uniform emergence. Sucrose has various effects on seed emergence and germination depending on the concentrations; 30 g/L elicited the highest germination, while 10 g/L improved seed emergence rate with higher uniformity. The highest seed germination was achieved on ¼-MS medium, although 0-MS strength recorded faster and more synchronized germination. The development of A. nubica seedlings was influenced by MS medium strengths and sucrose concentrations. Full MS medium produced the highest shoot length and the highest vigor index with the addition of 20 g/L sucrose and the maximum root length with 50 g/L sucrose. Also, 30 g/L sucrose gave the maximum number of nodes and the maximum root/shoot ratio. However, ½-MS strength yields the highest seedling biomass with 30 g/L sucrose. This is the first successful report on the seed germination and seedling growth of A. nubica in vitro.