Effect of Coffee Residue on the Growth of Several Crop Species.

Increasing coffee production inevitably produces a large amount of coffee residue. This residue has recently been utilized partly as the mainor a secondary-material for manure, yet, information about the effect of coffee residue on crop growth is scarce. Our Studies indicated that the incorporation and mulching of the residue did not affect the growth of soybean and broadbean did inhibit weed growth. This inhibition was apparently due to the effect of allelochemicals of the residue9). Further studies with the water extracts of coffee residue have clearly indicated that it has the ability to inhibit seed germination and root growth of some plant speciess, and it is therefore considered to be a useful organic matter rich in herbicidal effects. The objective of this research was to examine the effect on the growth of 12 species of crops grow in pots filled with a soil containing coffee residue.