Allelopathic potential of leaves of Esenbeckia leiocarpa Engl. (Rutaceae) on germination and seedling growth of native species

• Grant number: 08/10716-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): March 01, 2009
• Effective date (End): December 31, 2009
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Flaviana Maluf de Souza
• Grantee: Vinícius Henrique de Oliveira
• Host Institution: Centro de Ciências Agrárias (CCA). Universidade Federal de São Carlos (UFSCAR). Araras , SP, Brazil

Abstract

This experiment belongs to a project entitled "Effects of Esenbeckia leiocarpa Engl. on the development of native tree species seedlings". The objective of this project is to test hypothesis on the effects of E. leiocarpa leaf extracts on the germination and seedling growth of E. leiocarpa and one more native tree species, which will be defined at the main project. Mature leaves will be colected in a seasonal semideciduous forest remnant (Campinas - SP, southeastern Brazil) during the dry and wet seasons to test for possible seasonality effects related to the concentration of allelopathic compounds. Aqueous extracts of the leaves will be prepared at seven different concentrations, and will be compared to a water and a polyethylene glycol (PEG 6000) solution controls. The germination bioassay will be conducted with four replicates of 25 seeds put in a growth chamber at 27oC ± 1oC and a 12-hour photoperiod; the seeds will be counted daily to record the germination speed and the percentage of germination. For the growth bioassay, the seeds will be previously germinated in distiled water and transferred to plastic boxes (ten seedlings and four replicates per treatment) and monitored until the emergence of the second non-cotiledonary leaf; the seedlings will be classified as normal or abnormal, and the normal seedlings will have their hypocotyl and root measured. The results will provide auto-ecological information about E. leiocarpa and help to understand its spatial patterning in seasonal semideciduous forests. (AU)