| dc.description.abstract | The increasing industrial demand for porang products makes the development of its cultivation important. The main challenge is the provision of quality seedlings, which can be addressed more efficiently through vegetative propagation methods such as tuber skin cuttings. The use of auxin growth regulators, such as NAA, is effective in accelerating root and shoot formation. This study aims to determine the effect of concentration and frequency of NAA application on the growth of shoots of porang plant tuber skin cuttings. This research was conducted at Jalan Galang, Pagar Merbau III Village, Lubuk Pakam District, Deli Serdang Regency and Biotechnology Laboratory, Faculty of Agriculture, University of North Sumatra from July to December 2024, using a group randomized design with 2 factors. The first factor is the concentration of NAA consisting of 0 ppm, 50 ppm, 100 ppm, 150 ppm, and the second factor is the frequency of NAA application consisting of spraying the 1st (early seedling) and 2nd (early seedling and 1 week day after seedling). The results showed that different concentrations of NAA auxin caused significant differences in the growth of shoots of porang tuber skin cuttings. Treatment with a concentration of 100 ppm (A2) can increase shoot growth, wet and dry weight of plants, chlorophyll and stomata of porang tuber skin cuttings. The frequency of spraying at the beginning of sowing (P1) gave the best results for plant height, tuber weight, chlorophyll a, b, and total, α amylase enzyme and protein, while the frequency of spraying at the beginning of sowing and 7 HSS (P2) showed a higher number of shoots, number of leaves, stem diameter, root length, root wet weight, crown wet weight, root dry weight, and crown dry weight. The interaction between the concentration and frequency of NAA auxin administration gave higher results in the number of leaves at 3 weeks of age and tuber weight. | en_US |
