|Author:||Currie, R. S. ; Klocke, N. L.|
|Book Group Author:||NA|
A field study was conducted near Garden City, Kansas, USA, in 1997, with irrigated maize to determine how the integration of a terminated winter wheat cover crop with various atrazine rates would affect Palmer amaranth (Amaranthus palmeri) control and maize water use efficiency (WUE). Without atrazine, the presence of a winter wheat cover crop, killed in the boot stage, resulted in a 3-fold weed biomass reduction in irrigated maize. The highest rate of atrazine completely masked the weed control effect of the cover crop, producing a greater than 15-fold reduction regardless of the presence or absence of the cover crop. A terminated winter wheat cover crop without atrazine elevated maize yield in only 2 of 9 location-year, and in one instance, depressed yield. However, a terminated wheat cover crop elevated maize yield in 6 of 9 location-year combinations when used in conjunction with 1.6 kg atrazine/ha. Although increases in WUE associated with reductions in soil water evaporation produced by the cover crop seemed to be responsible for some of the increase in maize grain yield and stored soil water at the end of the summer growing season, end of season Palmer amaranth biomass had a more profound impact.
|Pages:||709 - 716|
allelopathy, atrazine, biomass, chemical control, covercrops, crop yield, herbicides, maize, plant water relations, soil water,water use efficiency, weed control, weeds, wheat, winter wheat, Kansas,USA, Amaranthus palmeri, Triticum, Triticum aestivum, Zea mays,Amaranthus, Amaranthaceae, Caryophyllales, dicotyledons, angiosperms,Spermatophyta, plants, Northern Plains States of USA, West North CentralStates of USA, North Central States of USA, USA, North America, America,Developed Countries, OECD Countries, Great Plains States of USA,Triticum, Poaceae, Cyperales, monocotyledons, Zea, Field Crops (FF005)(New March 2000), Plant Water Relations (FF062), Plant Production(FF100), Plant Cropping Systems (FF150), Weeds and Noxious Plants(FF500), Pesticides and Drugs; Control (HH405) (New March 2000)