Weeds compete for moisture, nutrients, and light. In addition, weeds make harvesting and grain storage difficult and grain quality low. Weeds in Kansas soybean fields have been estimated to cause losses of 13 million dollars in production each year. Therefore, weeds need to be controlled effectively and economically, while maintaining maximum soybean yields.
G enetically modified soybeans offer new and exciting methods for controlling weeds.
Genetically modified soybeans must maintain high yield potential, excellent herbicide tolerance, and resistance to iron chlorosis if they are to be fully implemented as a practical alternative to conventional soybeans in central Kansas. F ield studies were conducted in 1998 and 1999 at Ashland Bottoms, Manhattan, and Belleville, Kansas to evaluate the yield of Roundup Ready soybean varieties and their response to Pursuit or Raptor herbicides. Greenhouse studies were conducted in the winter of 1999 to determine the effects of Roundup or Pursuit on the expression of iron chlorosis in Roundup Ready and conventional soybean varieties. Plots were maintained weed free. Furthermore, in both years, the yield of Roundup Ready soybean varieties was similar when treated with Pursuit, Raptor, or Roundup herbicides.