Biotemas (Sep 2012)
Allelopathic interaction of Jatropha curcas L. with Helianthus annuus L. and Zea mays L.
Abstract
The goals of this work were to evaluate the effect of the allelopathic interaction of Jatropha curcas with Helianthus annuus and Zea mays from root exudates, as well as to evaluate how these exudates influenced the seeds of these species. Four replicates were made with seeds that were germinated in germiteste paper, which was previously autoclaved. Dormancy of the H. annuus seeds was broken by pre-cooling them in a freezer for seven days at 5°C. Jatropha curcas seeds were cultivated for eight days in a germination chamber under a controlled temperature and photoperiod. These seedlings were then discarded and the same substrate was used to germinate 50 H. annuus seeds; only distilled water was used as the control. The root exudates of H. annuus tested on J. curcas and the allelopathic interaction between J. curcas and Z. mays were carried out using the same methodology. Statistical analysis indicated that J. curcas has an inhibitory effect on the time and average speed of germination of H. annuus seedlings and Z. mays has an inhibitory effect on the germination of the seeds of J. curcas.