Mechanical or chemical thinning in seed production of a Phalaris aquatica L. cultures

In an experimental area of a dense Phalaris aquatica L. sward, seeded at th e rate of 8,5 Kg/ha in drill at 30cm apart, two subareas were thinned out t o every other row, one removing the plants mechanically and another applyin g glyphosate. The experimetal units were distributed in an experimental des ign of complete randomized plots, with three replicates. The seed was harve sted in three consecutive years. Seed production/ha was not affected (P con gruent to 0,05) either by the thinning out or the way it was done. The resu lts are discussed in relation to the yield components: density and length o f panicles.