Enhanced Germination and Early Growth of Tacunan Dwarf Coconut (Cocos nucifera L.) through Coconut Water and Auxin Injection

Abstract

Coconut (Cocos nucifera L.) propagation via seednuts is limited by slow and inconsistent germination restricts uniform seedling production in coconut. This study evaluated the effectiveness of coconut water, a natural source of phytohormones, compared with synthetic auxin (NAA) on the germination and early seedling growth of Tacunan Dwarf coconuts under nursery conditions. The experiment was arranged in a randomized complete block design with four treatments: control (no injection), 200 mL NAA + 200 mL distilled water, 200 mL coconut water + 200 mL distilled water, and a combination of NAA + coconut water (100 mL each) + 200 mL distilled water, with four replications. Treatments were applied by injecting the solution near the soft eye at 10 ml/seednut, and germination and growth parameters were recorded over 120 days. Coconut water significantly reduced the time to plumule emergence (61.00 days), produced the longest shoots (142.62 cm), shortened mean germination time (49.52 days), and increased both germination index (0.1527) and seedling vigor index (22,120.44), outperforming both NAA alone and the combined treatment, with a germination rate of 72%. In contrast, NAA resulted in the highest germination percentage (90.67%) but lower seedling vigor, while the combined treatment produced intermediate responses, suggesting no clear synergistic effect between the two stimulants. These findings demonstrate that coconut water can serve as an effective natural alternative for enhancing germination speed and early seedling growth of coconut seedlings.