Evaluation of pre-sowing treatments on germination and seedling growth of Carissa carandas L.

Abstract

Carissa carandas (karonda) is a hardy, drought-tolerant shrub with high horticultural and medicinal value, but its propagation is limited by poor seed germination due to a hard seed coat. To address this challenge, a study was conducted to evaluate the effect of various pre-sowing treatments on germination and seedling growth. The experiment was carried out in the nursery of the Silviculture and Agroforestry Department, College of Forestry, Sirsi, Uttara Kannada, Karnataka. Seeds of C. carandas were collected from the scrub forests of Ballari to ensure genetic diversity and viability. Seven treatments were applied, including control, organic (cow dung and cow urine), physical (hot water and water soaking), and chemical (KNO₃ and GA₃) methods. Among these, GA₃ 50 ppm for 1 hour (T7) recorded the highest germination percentage (40.60%) and the fastest germination (8.00-11.67 days), followed by KNO₃ 2% soaking (T6). Significant improvements in seedling growth parameters such as plant height, number of leaves, collar diameter, shoot and root length, and root-shoot ratio were observed in T5 (hot water), T6, and T7 treatments. These results indicate that GA₃ and KNO₃ are effective pre-sowing treatments for enhancing seed germination and seedling vigor in Carissa carandas, offering potential for better propagation and establishment in arid and semi-arid regions.