The Effect of Vitamin B1 Application on The Growth of Cocoa Seedlings

Vitamin B1 is a vitamin that has a very important role for plants. The application of vitamin B1 (thiamin) is expected to increase plant growth, including in the seedling phase. This study aims to determine the effect of vitamin B1 application, variety and interaction of vitamin B1 and variety on the growth of cocoa seedlings. The research was conducted in the gauze house. Faculty of Agriculture, Universitas Sumatra Utara Medan, from July to December 2023. This study used a factorial randomized block design (RBD) consisting of 2 treatment factors. The first factor was cocoa plant variety consisting of three levels namely ICS 60, RCC 70, Lindak, and the second factor was vitamin B1 application (concentration of 10 ml/liter) consisting of 4 application method namely control, soaking seeds, foliar aplication and soaking seed + foliar application. Observation variables were plant height, stem diameter, number of leaves, leaf area. The results showed that vitamin B1 application, variety, interaction between varicty and vitamin B1 did not significantly affect all observation variables except vitamin B1 application significantly affected stem diameter of 6 week old cocoa seedlings. However, based on several observation variables, it is known that seedlings of Lindak variety which sprayed vitamin B1 (V3B2) had better growth than other treatment combinations.