Brhanu Hunde, Yohannes Petros and Manikandan Muthuswamy
Plant may be directly or indirectly affected their phenotypic characters, when it is growing in intercropping system. The phenotypic changes caused by one of the factor releasing the allelochemicals from different plants species. It was observed that when the arabica coffee were growing with agro-forestry plants. The seeding phenotypic characters especially their height was reduced. Therefore, the research was initiated to find out the factors which affect the seedling phenotypic characters of arabica coffee variety when is growing with selected agro-forestry tree species. It was noted that aqueous extracts at a concentration of 5, 10 and 20% had an inhibitory effect on arabica coffee germination and effect was found higher than control and treatments. The extracts brought about considerable inhibitions in the germination of coffee seed and in the phenotypic variation in growth of radicle and plumule. In all extracts, the degree of inhibition increased with the increase in the concentrations of the extracts thus suggesting that the effects of the extracts were concentration dependent. However, the results obtained also tend to suggest that the degree of retardation in seed germination and seedling phenotypic variations were more in the extracts derived from the E. globulus leaf than those from the Albizia gummifera and Cordia africana. Therefore, an arabica coffee seedling phenotypic character was highly affected by Eucalyptus globules leaf extract.
