Allelopathic effect of eucalyptus camaldulensis leaf extract on germination and growth of mungbean

Abstract

Abstract : Allelopathic effect of Eucalyptus leaf extract on mungbean was studied for making a good compatible tree-crop association; two separate experiments were conducted during 2009. The first experiment on germination of mungbean seeds was conducted in growth chamber of the Department of Wood and Forest Sciences, Laboratory of the Centre for Forest Research (CFR), Universite Laval, Quebec, Canada. The second pot experiment was conducted in the field of the Department of Agroforestry and Environment, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh to observe the growth performance of mungbean. The study consisted of seven treatments having different aqueous extracts i.e. 0% (control), 2.5, 5.0, 7.5, 10.0, 12.5 and 15.0 % of eucalyptus leaves. In seed germination experiment, both rate of germination and radicle growth in lower concentration treatments showed better performance than in higher concentration treatments, while no significant variation was observed between 0% and 2.5% aqueous extract solutions. In growth study, all parameters of mungbean performed better in lower aqueous concentration treatment and the performances were found gradually poor with increasing the concentrations. Regarding weed growth, the highest weed biomass (0.42 g pot'1) was recorded in control (0%) treatment, which was decreased drastically when leaf extract solution was applied. Interestingly, no weed was grown at 15.0% aqueous extract solution. The study suggest that Eucalyptus leaf extract at lower concentration may not have negative effect on mungbean germination and growth, while higher concentration might have great potential for use in organic weed control strategies.