in order to study the effect of different redroot pigweed (amaranthus retroflexus) density on yield, yield components of soybean cultivar and determining competitive cultivar, a field experiment was carried out at mazandaran agricultural research station 2006. experiment was set up at a randomized complete block design with five rates of pigweed (0, 4, 8, 12 and 16 plant per square meter) and t...

a field experiment was conducted to investigate the spatial distribution of weeds at the sari agricultural sciences and natural resources university in 2011. field was divided into 42 grids (1.5×1.5 feet) then all samples were taken from grids intersection points before corn planting, after harvesting and ear emergence stage. weed maps and semi variance analysis carried out using rw99 and gs+ s...

in this research corn were planted in 3 densities (8, 12, 16 plant/m2) in two planting patterns (single and double-row) with seven summer weed species, including redroot pigweed, green foxtail, annual bluegrass, common lambsquarter, jimsonweed, black nightshade and johnsongrass were planted. temperature, quality and quantity of light reaching to soil surface were measured and the number of emer...

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is a pest of various fruit, vegetable, Wber, and seed crops; including cotton. Lygus spp. populations often build on alternate host plants before moving to cotton, and in the midsouthern U.S. wild host plants, such as pigweed (Amaranthus spp.), play a major role in L. lineolaris population development. Three isolates of the entomo...

Abstract Tolpyralate is an herbicide that usually mixed with atrazine for broad-spectrum weed control in corn. Previous research has provided information on the effective dose (ED) of tolpyralate applied alone and a 1:33.3 mixture atrazine; however, commercially at 30 to 40 g ai ha −1 minimum 560 atrazine. Therefore, five field trials were conducted over 3 yr (2019 2021) determine ED complement...

Understanding the spectral characteristics of crops in response to stress caused by weeds is a basic step improving precision agricultural technologies that manage field. This research focused on competition between corn (Zea mays) and redroot pigweed (Amaranthus retroflexus), common weed strongly reduces yield. The aim this was characterize physiological changes occur during early growth becau...