Dry Matter Production and Partitioning in Arabica Coffee Seedling as Affected by Lime and Phosphorus Mineral Fertilizer at Jimma, Southwestern Ethiopia

Abstract

Nursery experiment was conducted at Jimma Agricultural Research Center, southwestern Ethiopia, to investigate dry matter production and its partitioning into above and below ground parts of Arabica coffee seedlings under different lime and P mineral fertilizer rates and establish optimum combination of these agricultural inputs that produce seedlings with better dry matter yield for field planting. Six lime rates [0, 2.31, 4.62, 6.93, 9.24 and 11.55 g/2.5 kg soil (pot)] and four P rates (0, 250, 500 and 750 mg P/ pot) were factorially combined and laid out in a randomized complete block design with three replications. Results showed that the main effect of lime and P mineral fertilizer significantly (P < 0.01) affect stem, leaf, root and total dry matter production and shoot to root ratio of coffee seedlings. The highest dry matter and shoot to root ratio was recorded from seedlings treated with 2.31 g lime and 750 mg P/pot. Similarly, the interaction of lime and P significantly (P < 0.01 or P < 0.05) affect the above mentioned agronomic parameters, except shoot to root ratio. The highest and insignificant dry matter recorded from seedlings treated with a combination of 0 g lime and 750 mg P/pot and 2.31 g lime and 250 mg P/pot. Thus, it is concluded that vigorous coffee seedlings with high dry matter content for field transplanting can be produced by applying P at a rate of 750 mg P/pot or by applying a combination of 2.31 g lime and 250 mg P/pot. But, further investigations should be continued under field conditions to evaluate growth and yield response of coffee trees and row and cup quality of green beans to varying levels of lime and P mineral fertilizer and establish economically profitable levels of these agricultural inputs for sustainable coffee production in the country by taking into account coffee cultivars, seasonal growth and fruiting pattern, management practices and climatic conditions.

Keywords: Acid soil, Arabica coffee, dry matter partitioning, dry matter production, lime, P mineral fertilizer