The impact of close spacing on yield of arabica coffee under contrasting agro-ecologies of Ethiopia

Determination of Appropriate Planting Space and Vertical Number s for Hybrid Arabica Coffee at Yeki District, Southwestern Ethiopia

“…The increase in bearing primary branches per tree with increasing tree population number has been attributed to efficient utilization of environmental inputs, viz. light, moisture and nutrients, until the biological optimum is attained [16]. In the same way, the non-bearing primary branch number was linearly increased along with plant population number (Table 1).…”

“…According to [15] report, the productivity of densely planted coffee is generally much greater than that of traditional plantings. It has been also reported that a closely planting space favors the individual coffee plant to utilize the environmental resources such as light, moisture and nutrients throughout the growing period [16]. In other study, closely planted coffee results almost a complete ground coverage and better uptake of available soil nutrients by denser rooting [17].…”

“…The coffee yield increases with population density of coffee tree, it could be attributed to efficient utilization of environmental inputs, viz. light, moisture, nutrients, until the biological optimum is attained Taye et al, [16]. Moreover, the free growth habit of coffee gave higher yield as compared to multiple stem uncapped and multiple stem capped growth habit.…”

“…This result could be associated with high coffee tree population density with enhanced branching leading to insufficient utilization of nutrients for each individual tree. Moreover, it might be due to less light absorption by individual tree due to high mutual shading effects of closely planted coffee trees [31].…”

Natural occurrence of Beauveria bassiana in Hypothenemus hampei (Coleoptera: Curculionidae) populations in unsprayed coffee fields

“…The H. hampei infestation level in our study varied considerably between years, and between farms; though no significant differences were found between sampling dates, variations were also observed within seasons. The low H. hampei infestation in 2005 compared to 2004, illustrates the cyclic behavior of H. hampei populations, which might be associated with the biennial cyclic production of berries on the plant, where years of high berry production alternate with years of low berry production (Chamorro et al, 1995;Kufa et al, 2001). The H. hampei infestation level in 2005 in our study did not reach 2%, which is considered the economic damage threshold for H. hampei in traditional coffee production systems (Borbó n, 2003).…”