Potencial alelopático de Calotropis procera Ait. R. Br E Caesalpinia pyramidalis Tul. na emergência e crescimento inicial de três espécies agrícolas.

Abstract

The term allelopathy is used to indicate the direct or indirect stimulatory or inhibitory effect that an organism imprints on another through the production and release of chemical compounds in the environment. The objective of the present work was to analyze the allelopathic potential of Calotropis procera and Caesalpinia pyramidales on the emergence and initial growth of Vigna unguiculata, Citrullus lanatus and Sorghum bicolor. The experiment was carried out in a greenhouse of the Center of Sciences and Technology Agrifood - CCTA/UFCG, using a completely randomized design (DIC), with four treatments (leaves of C. procera, leaves of C. pyramidalis, lava sand and control) and fifteen repetitions. They were placed in plastic containers, with a capacity of 500 ml, containing soil and irrigated for 15 days until sowing of V. unguiculata, C. lanatus and S. bicolor, and the experiment was completed one month after its beginning. The parameters analyzed were: emergence percentage, IVE, stem diameter, plant height, fresh matter and dry matter of shoot and root. All the treatments presented 100% emergency. In the IVE parameter, the catingueira was positively related to sorghum and watermelon. There was an increase in shoot diameter, shoot length and bean root, watermelon and sorghum by the species tested, and the results were significant in all analyzes of these factors. C. procera and C. pyramidalis have a positive allelopathic effect on vegetative aspects of the target species. The studied species can be cultivated consorciadas, without being harmed for the agricultural species.