AUTOTOXICITY IN TOUGH LOVEGRASS ( Eragrostis plana )

Abstract

ABSTRACT Autotoxicity in tough lovegrass has been analyzed in the field, but has never been tested in allelopathy bioassays. Therefore, this study aimed to verify and compare the autotoxicity of leaves and roots from aqueous extracts of tough lovegrass on its germination and early seedling growth. Extracts of green leaves (GL), senescent leaves (SL), and roots (R) at concentrations of 0.05, 0.15, and 0.25 g mL-1 were analyzed on how they affected seed germination and seedling growth. The extracts, regardless of the source or concentration of the material used, have significantly reduced germination percentage, index of germination speed, and root growth of seedlings of tough lovegrass. Effects on mean germination time and shoot length varied according to the origin and concentration of the extracts. GL, at concentrations 0.15 and 0.25 g mL-1, showed the most damaging effect. In tough lovegrass, autotoxicity is a mechanism that may be involved in the control of germination and plant growth, which could explain the distance between their clumps in the field.

Keywords

• allelopathy
• aqueous extracts
• Eragrostis plana
• germination