Effects of Paraquat on Harvesting and Quality of Bermudagrass (Cynodon dactylon) Seed

Abstract

The effects of chemical desiccation of bermudagrass [Cynodon dactylon(L.) Pers.] before seed harvest on seed yield and quality were studied. Harvest of 57.3% of available seed was obtained with the stripper harvester after chemical desiccation with paraquat (1,1′-dimethyl-4,4′-bipyridinium ion). Only 44.6% of the available seed was harvested by direct combining after paraquat treatment. This was significantly better than the 31.2% seed obtained by harvesting using the conventional swathing and combining method. Paraquat severely reduced germination of unhulled seeds. The inhibitory effects of paraquat application were removed by hulling or by hulling and scarifying the caryopses before germination. Significant improvement in germination of all seed (unhulled, hulled, and hulled-scarified) resulted from use of 0.2% KNO3rather than water as a substrate moistening agent.