Effect of plant growth regulators and nutrient- based seed treatments on germination and seedling vigour of Acid Lime (Citrus aurantifolia swingle) cv. Kagzi Lime under shade-net house

An investigation was conducted during 2024–2025 at Pt. Kishori Lal Shukla College of Horticulture and Research Station, Rajnandgaon, Chhattisgarh, to evaluate the effect of different plant growth regulators and nutrients on seed germination and seedling growth of Acid lime (Citrus aurantifolia Swingle) cv. Kagzi lime under shade-net conditions. The experiment was laid out in a Completely Randomized Design with 13 treatments comprising various concentrations of GA₃, NAA, KNO₃ and thiourea, replicated thrice. Significant variations were observed among treatments for all germination indices and seedling vigour parameters. GA₃ @200 ppm consistently outperformed other treatments, recording the minimum days to germination (20.93 days) and 50% germination (23.60 days), along with the highest germination percentage (90%). It also produced the maximum seedling vigour index-I (3892.56) and seedling vigour index-II (1090.31). The untreated control exhibited delayed germination (30.73 and 37.73 days respectively) and the lowest germination percentage (60%). The results demonstrate that GA₃ @ 200 ppm is highly effective for improving germination behaviour and enhancing early seedling growth of Acid lime under protected nursery conditions.