Cultivated species sensibility to aqueous extract of Eragrostis plana with high total phenolic content

Abstract

Eragrostis plana is one of the most invasive alien species in pasture lands of southern South America, due to its biological and ecological characteristics. The objectives of the present work were to quantify the total phenols in an aqueous extract from incubated dry matter of E. plana shoots and to evaluate its effect on seed germination and seedling development of three cultivated species. The amount of total phenols present in the aqueous extract of the degraded biomass was approximately 0.75 g L-1, which is equivalent to 1.35 % of the dry mass of the shoots. Alfalfa was the species that showed greater sensitivity to the aqueous extract, being impaired in both germination and seedling development. Palisade grass and wheat were harmed only during seedling development. Palisade grass was the only species that benefited from the aqueous extract, presenting a smaller number of abnormal seedlings. More studies are needed to characterize the allelochemicals present in the aqueous extract of E. plana phytomass, its release rate, and its behavior in soils of infested areas.

Keywords

• urochloa brizantha cv. marandu. medicago sativa cv. monarca. triticum aestivum cv. ipr catuara. phytochemical ecology. allelopathy.