Allelopathic influence of the aqueous extract of Jatropha curcas L. leaves on wild Cichorium intybus

摘要

The communication presents an evaluation of the allelopathic effect of the aqueous extract of physic nut (Jatropha curcas L.) leaves on the early development of wild chicory (Cichorium intybus) seedlings. The experiment was performed in Palotina City, State of Paraná, Brazil. The physic nut leaves were harvested and then crushed in a blender using the proportion of 1 L of distilled water for each 200 g of leaves resulting in a crude extract of 100%. The experiments were conducted in 6 trials with 8 repetitions. The dilutions of 80, 40, 20, 10, 5 and 0% (only distilled water) were made using the crude extract. Data was subjected to statistical analysis (regression at 1% of probability). Aqueous extract of physic nut leaves showed an inhibitory allelopathic effect on the development of wild chicory (sugarloaf variety) which increased with enhanced concentration, presenting negative linear tendency, except for the variable fresh weight of shoots.