Effect of isolated compounds of sugarcane leaves on seedling growth of L. sativa

SAMPIETRO, D.A.; VATTUONE, M.A.; ISLA, M. I.

Tucumán (Argentina)

Congreso; XXI Annual Meeting of Tucuman Biology Society; 2005

Tucuman Biology Society (publicado en Bio Cell 29 (1), 90, 2005)

Allelopathy is a direct action (negative or positive) of a compound released from a plant on the growth and/or development of other plant. Recently in a bioassay-guided isolation we isolated vanillic (VA), syringic (SA) and ferulic (FA) acids. The aim of this work was to evaluate the phytotoxic effect of these acids alone and in mixtures. Seeds of L. sativa were placed on plates of 24 wells, on Whatman Nº1 paper discs. The phenolics alone, in binary mixtures and in a ternary mixture were assayed between 0.1 and 2.5 mM. Plates were placed on a growth chamber (25±1ºC with a 12 h photoperiod at 400 mol/m2, PAR). FA, SA and VA inhibited the radicle elongation at concentrations beyond 0.1 mM. The concentrations needed to reduce 50% radicle elongation (IC50) were 0.75±0.04 mM (VA), 2.25±0.08 mM (FA) and 2.50±0.07 mM (SA). The IC50 of the mixtures were 0.90 ±0.12 (SA + VA), 1.20±0.10 (FA+VA), 2.50±0.20 (SA+FA) and 1.40±0.17 mM (FA+VA+SA). VA was the most inhibitory on radicle elongation of L. sativa. The phenolic acids were less phytotoxic assayed in mixtures than alone, suggesting an antagonistic interaction among them. More studies about the impact of these  compounds on the agroecosystem are in progress.