Effectiveness of Germination Stimulants on the Viability and Vigor of Arabica Coffee Seeds of Kopyol Variety and Lini S 795 Variety

This study is a laboratory-based experimental research aimed at evaluating the effectiveness of germination stimulants on the viability and vigor of Arabica coffee (Coffea arabica L.) seeds, specifically the Kopyol and Lini S 795 varieties, which are important plantation commodities in Bali Province. The decline in Arabica coffee production due to aging plants has increased the need for high-quality seeds, yet seed dormancy and hard seed coats remain major barriers to optimal germination. The objectives of this research were to determine the influence of various germination stimulants on seed physiological performance and to identify the most effective treatment for enhancing germination and early seedling growth. The experiment was conducted in December 2024 at the UPTD Laboratory of Seed Testing and Certification for Food Crops, Horticulture, and Plantation, Bali Province, using a Nested Design with two factors: coffee varieties (Kopyol and Lini S 795) and germination stimulants (water, 25% young coconut water, 100 ppm GA₃, 20% H₂SO₄, and 0.3% KNO₃). Observed parameters included germination rate, maximum growth potential, germination speed, uniformity, radicle length, shoot height, vigor index, fresh weight, and dry weight. The results showed that germination stimulants significantly improved both viability and vigor of Arabica coffee seeds. The 0.3% KNO₃ treatment applied for 24 hours produced the highest germination rate (92%), maximum growth potential (94%), and vigor index. The Kopyol variety exhibited superior physiological responses compared to Lini S 795. Based on these findings, the application of 0.3% KNO₃ is recommended as the most effective germination stimulant to enhance the physiological quality of Arabica coffee seeds, particularly the Kopyol variety, supporting rejuvenation programs for coffee cultivation in Bali Province.