Abstract: An experiment was carried out to study the influence of three commercial rootstocks,
i.e., Rangpur Lime, Rough Lemon and Trifoliate Orange on the growth characteristics, grafting success, biochemical and nutrient accumulation in the leaves of Darjeeling mandarin. Data were collected 180 days after grafting for growth parameters and one year after grafting for biochemical and nutrient accumulation by the scion of Darjeeling mandarin. The results revealed significant variation across the rootstocks under study. Rough lemon recorded the highest grafting success (91.25 %) followed by Rangpur lime (87.50 %). In terms of growth parameters rough lemon demonstrated the highest rootstock length (22.26 cm), scion length (11.72 cm), and leaf area (39.59 cm²). Darjeeling mandarin was recorded highest starch content (2.9 mg/g), total sugar (1.31 mg/g), total protein (3.98 mg/g), and total phenol content (0.941mg/g). Higher proline content (1.9 mg/g) in rough lemon indicates a high stress tolerance. Trifoliate Orange recorded the lowest scion length (4.87 cm), leaf area (17.92 cm²) and total sugar content (0.89 mg/g). Concerning macronutrient and micronutrient accumulation, Rangpur Lime recorded the highest calcium (2.35 %), magnesium (0.42%) and iron content (149.8 %). Thus, the findings revealed that Rough Lemon and Rangpur Lime are the most promising rootstocks for improving growth, nutrient uptake, and biochemical traits of Darjeeling Mandarin, making them ideal rootstocks for commercial propagation on Darjeeling mandarin.
