Banco de sementes de plantas espontâneas após cultivo do milho sob cobertura de palha de babaçu

The objective of this research was to analyze qualitative and quantitative aspects of the seedbank of spontaneous plants before and after cultivation of green corn under cover of babassustraw. Soil sampling was performed before and after the implementation of the experiment inan area of the State University of Maranhao. There were 40 trays arranged in a greenhousewhose emergence occurred at 15, 30, 45, 60, 75 and 90 days after implantation of the experiment.The density, frequency and importance value index were calculated. Before cultivation,2049 individuals emerged in two families of the Monocotyledons and eight of the Eudicots. Aftercultivation there were 118 in two families of Monocotyledons and five of Eudicots. Babassustraw had a suppressive effect on the spontaneous plants, mainly on the eudicots. Babassustraw reduced the number of individuals in the Cyperaceae family whose species of highestimportance was Cyperus rotundus.