the effect of planting pattern of corn (zea mays l.) in reducing foramsulfuron dose

in order to evaluate of using planting pattern for reducing herbicides dose in corn (single cross 704), a field experiment was conducted in 2007 at research field of collage of agriculture, islamic azad university branch of takestan. the experimental design was randomized complete block with 18 treatments and using factorial design with 4 replications. treatments consisted of corn planting pattern in 3 levels (single row, rectangular twin row and crinkle twin row), and weed control treatments in 6 levels (rates of 1, 1.5, 2, 2.5 l/ha foramsulfuron, a weed free as control and full season hand weeding control). biomass of weed species 15 and 45 days after post emergence herbicide application, and seed yield of corn were measured. results of statistical analysis showed that different dose of herbicide in each planting pattern had a various effect on weeds. application of low rates of herbicide in crinkle planting pattern was similar to higher dosages of herbicide in rectangular and single planting pattern. the most seed yield was occurred in the crinkle planting pattern with rate of 2 l.ha-1 foramsulfuron and the lowest seed yield was belong to single row planting pattern. environmental and economical advantages can be obtained by reducing herbicide rates, and selecting an appropriate planting pattern.