Coffee seedlings growth and nutrient accumulation affected by application of different rates of nitrogen, zinc and boron fertilizers at Dilla, Ethiopia

A proper coffee seedling management is required for successful field establishment. Pot experiment was conducted to evaluate different rates of nitrogen (N), zinc (Zn) and boron (B) on the seedling growth of coffee varieties. It was conducted under lath house condition in complete block design (CBD) with three replications. Two varieties with three levels of nitrogen (0g, 0.295g and 0.59g), zinc, (0mg, 1.62mg, 3.24mg) and boron (0 mg, 0.77mg 1.54mg) were considered. The results indicated that the application of nutrients significantly affected the agronomic performances of coffee seedlings. The average number of roots plant-1 was significantly affected by varieties and zinc rates. The highest result (42 roots plant-1) was recorded by the application of 3.24mg Zn plant-1.The highest seedling height (48.2cm) was observed by the application of 1.54mg B plant -1 and 0.59 g N plant -1 on coffee Fayate variety while 48.1cm was observed by the application of 0.295g N plant -1 and 0.77mg B plant -1 on variety Odicha. The highest main branch length, 6.9cm and, 6.8cm, were obtained by the application of 0.59g N plant -1, 1.54mg B plant -1 and 1.62mg Zn plant -1 on variety Odicha and Fayate, respectively. Regardless of varietal differences, the highest above ground biomass yield was obtained by the application of 0.59g N plant-1 (21.2g plant-1), 0.77mg B plant -1 (19.3g plant1) and 1.62mg Zn plant-1 (17.8gm plant -1). The highest biomass yield obtained from variety Odicha (18.2g plant-1) followed by variety Fayate (15.9g plant). Three way interaction of variety, nitrogen and boron resulted in significant (p<0.05) effects on coffee seedlings biomass. The application of 0.59g N plant-1 and 0.77mg B plant-1 gave the best results on both varieties despite their differences. In most of the cases, 0.59g N, 0.77mg B and 1.62mg Zn plant-1showed significantly the highest results which is recommended for the best and wider coffee seedling multiplication