Goosegrass is one of the worst agricultural weeds on a worldwide basis. Understanding of its interference impact in crop ifeld wil provide useful information for weed control programs. Field experiments were conducted...Goosegrass is one of the worst agricultural weeds on a worldwide basis. Understanding of its interference impact in crop ifeld wil provide useful information for weed control programs. Field experiments were conducted during 2010–2012 to determine the inlfuence of goosegrass density on cotton growth at the weed densities of 0, 0.125, 0.25, 0.5, 1, 2, and 4 plants m–1 of row. Seed cotton yield tended to decrease with the increase in weed density, and goosegrass at a density of 4 plants m–1 of row signiifcantly reduced cotton yields by 20 to 27%. A density of 11.6–19.2 goosegrass plant m–1 of row would result in a 50%cotton yield loss from the maximum yield according to the hyperbolic decay regression model. Bol production was not affected in the early growing season. But bol numbers per plant were reduced about 25%at the den-sity of 4 plants m–1 of row in the late growing season. Both cotton bol weight and seed numbers per bol were signiifcantly reduced (8%) at 4 goosegrass plants m–1 of row. Cotton plant height, stem diameter and sympodial branch number were not affected as much as cotton yields by goosegrass competition. Seed index, lint percentage and lint ifber properties were unaffected by weed competition. Intraspeciifc competition resulted in density-dependent effects on weed biomass per plant, 142–387 g dry weight by harvest. Goosegrass biomass m–2 tended to increase with increasing weed density as indicated by a quadratic response. The adverse impact of goosegrass on cotton yield identiifed in this study has indicated the need of effective goosegrass management.展开更多
基金funded by grants from the National Key Technology R&D Program of China (2012BAD19B05)the Fundamental Research Funds for Central Public Welfare Research Institutes, China (SJB1005)
文摘Goosegrass is one of the worst agricultural weeds on a worldwide basis. Understanding of its interference impact in crop ifeld wil provide useful information for weed control programs. Field experiments were conducted during 2010–2012 to determine the inlfuence of goosegrass density on cotton growth at the weed densities of 0, 0.125, 0.25, 0.5, 1, 2, and 4 plants m–1 of row. Seed cotton yield tended to decrease with the increase in weed density, and goosegrass at a density of 4 plants m–1 of row signiifcantly reduced cotton yields by 20 to 27%. A density of 11.6–19.2 goosegrass plant m–1 of row would result in a 50%cotton yield loss from the maximum yield according to the hyperbolic decay regression model. Bol production was not affected in the early growing season. But bol numbers per plant were reduced about 25%at the den-sity of 4 plants m–1 of row in the late growing season. Both cotton bol weight and seed numbers per bol were signiifcantly reduced (8%) at 4 goosegrass plants m–1 of row. Cotton plant height, stem diameter and sympodial branch number were not affected as much as cotton yields by goosegrass competition. Seed index, lint percentage and lint ifber properties were unaffected by weed competition. Intraspeciifc competition resulted in density-dependent effects on weed biomass per plant, 142–387 g dry weight by harvest. Goosegrass biomass m–2 tended to increase with increasing weed density as indicated by a quadratic response. The adverse impact of goosegrass on cotton yield identiifed in this study has indicated the need of effective goosegrass management.
