Allelopathic interference of Eucalyptus tereticornis Sm. I. Growth performance of some agricultural crops

Abstract

Fifteen crops grown with Eucalyptus tereticornis plantations showed reduced growth patterns compared to those grown in the nearby open area. The crops categorized as cereals, vegetables, forages and oil yielding were grown in two sets : one where the parent plantation floor soil was replaced by the soil from the adjoining land while the second where original floor soil was retained. Relative growth rate as well as the absolute values in terms of biomass and height of the crops, assessed after 30 and 61 days, declined under either set under Eucalyptus monoculture compared to the open area. The decline was relatively more in case where original understorey soil was retained. Retardation of growth suggests some kind of interference being caused by the monoculture plantations. The involvement of the Eucalyptus phytotoxins (terpenes as well as phenolic acids) in reducing the crop growth is speculated, though the presence of poor edaphic conditions can not be denied.