Seedling competition between Pennisetum setaceum (Poaceae) and three native weeds of La Primavera wood, Guadalajara, Jalisco (México)

Abstract

Pennisetum setaceum (Forssk.) Chiov., 1923 is an exotic grass from the Arabian Peninsula that has been very successful as an ornamental plant worldwide in recent years. Unfortunately, it has proved to be a very competitive invader, causing ecological problems in several regions of the world. We don't know exactly how this species interacts with native weeds in Mexico. Our study aims to show the interactions of Pennisetum with three species of native weeds in the surroundings of the metropolitan area of Guadalajara, Jalisco, Mexico: Aeschynomene villosa var. longifolia (Micheli) Rudd, Desmodium aparines (Link) DC. and Paspalum notatum (Flüggé). The seeds of Pennisetum were tested in monospecific groups (competing against itself) and in association with each of the native species mentioned and with a treatment together with all the compound of the species mentioned, thus simulating what could happen in natural conditions upon the arrival of the seeds of P. setaceum in a degraded soil of Guadalajara. The results show how the biomass produced and the speed of growth of Pennisetum can be a real alarm for the conservation of local germplasm.