Allelopathy can be used to combat weeds, which can negatively interfere in various natural and cultivated environments. Among the weeds found in the Caatinga are Calotropis procera and Cenchrus echinatus. Thus, the objective was to evaluate the allelopathic effect of extracts from leaves, stems and roots of Ziziphus joazeiro on the germination and development of these species. Two portions of 50 g of each part ...