Effect of Fertilization and Sowing Density of Winter Wheat on Community and Biomass of Field Weed

Plot trials were carried out to study effect of fertilization and sowing density on community and biomass of field weed.The results showed that:17 species field weeds were found during the winter wheat growth stage,and the dominant species,weed biomass,weed density varied at different growth stage.Comparing with P0N0,the density and biomass increased with only N application,and there was a remarkable effect of N application on weed biomass in NP treatments.The weed biomass reached the maximum in low N application treatment.The biomass of PN45 was the greatest which increased by 51.8% comparing with P0N0,and the biomass decreased with the increase of N application.There was a remarkable effect of P application on weed biomass.The biomass of only P application increased 44.0% comparing with P0N0,and PN135 increased 24.0% comparing with P0N135.Weed biomass of low density treatment was greater than that of normal density,and biomass increased 82.9%.The results indicated that weed biomass and density could be controlled to promote growth of crop by applying N fertilization and increasing cultivation density.