Sustainability for Growth and Productivity of Arabica Coffee in Lowland Regions of Bengkulu Province

Arabica coffee usually grows well at the latitude of more than 700 m above sea level, but in Bengkulu Province, Indonesia the highland regions are mainly located in the conserved areas and prohibited for agricultural cultivation. These subsequent studies aimed to result in the most adaptive genotype of arabica coffee to the lowland environtment and the best planting gap of shading trees for improved coffee productivity.  Two types of technology included in these studies were grafting of arabica and robusta as entress and understump, respectively, and enviromental engineering at a lowland area by planting shading trees at different distances.  Four arabica entresses of S-1934, Kartika, Sigararutang and Andung Sari varieties were grafted with robusta understumps to produce so called four “robbika” genotypes.  The robbika stumps were grown in the lowland region under shading trees of legume species which were pre-planted with varous planting distances.  Results showed that four genotypes of robbika coffee grew better in the lowland region compared to all genotypes of arabica coffee as shown by parameters of growth, physiological characters and yield potential.  Environmental engineering treatments showed that the 2.5 x 2.0 m planting distance resulted in the best soil and microclimate conditions in the robbika plantation areas.