The Effect of Imazethapyr Reduced Dose on Red bean (Phaseolus calcaratus L.) Grain Yield and Yield Components at Competition with Velvetleaf (Abutilon theophrasti Medik.)

The field experiment was conducted in order to study the interaction of velvetleaf densities and Imazethapyr doses on yield and yield components of red bean in factorial randomized complete block design with four replications in 2013. The factors were included four levels of velvetleaf densities (0، 5، 10، and 15 plant. m-2) and five levels of Imazethapyr doses (0، 0. 25، 0. 5، 0. 75، and 1 lit. ha-1). Grain yield at weed-free plots with increasing herbicide dose did not change، but it is increased at other velvetleaf densities with increasing doses of herbicide. Grain yield at 4، 8، and 12 velvetleaf plant. m-2 densities at the recommended dose compared to no-herbicide plots increased by 43، 92، and 127%، respectively. The number of pods per plant at no-herbicide plots and 4، 8 and 12 velvetleaf plant. m-2 than velvetleaf weed-free plots reduced by 29، 44 and 48%، respectively. The number of grains per pod at densities of 4، 8 and 12 velvetleaf plant. m-2 than weed-free conditions reduced to 8، 12 and 4%، but the hundred grain weight did not affected by levels of weed densities and herbicide doses.