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...

Parthenium hysterophorus L. (congress grass, congress weed, carrot weed, wild feverfew, the “Scourge of India”) is an exotic weed that was accidentally introduced in India in 1956 through imported food grains.[1] It has become a common weed causing dermatitis of epidemic proportions.[2] The epithet “congress weed” refers to the US congress (who allocated the shipment for Pune, India).[3] In Pun...

introduction integrated weed management is based on combination of several management methods, while reducing the rate of the use of herbicides, will result in efficient management and sustainable weed control. ability of crop tolerance and prevent weed growth are two important traits in weed competition. an appropriate and suitable cultivar, has high yield potential in the presence of weed and...

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...

Martin M. Williams II Corresponding author. U.S. Department of Agriculture—Agricultural Research Service, Invasive Weed Management Research, University of Illinois, 1102 S. Goodwin Ave., Urbana, IL 61801; [email protected] The critical period for weed control (CPWC) identifies the phase of the crop growth cycle when weed interference results in unacceptable yield losses; however, the effect of ...

Rice bran application just after transplanting has been increasingly practiced as a herbicide-substitute for organic rice production in Korea. However, this practice is frequently reported to be unsatisfactory in weed suppression. An experiment with five treatments that combine flooding depth (shallow and deep), rice bran application level (low and high), and herbicide application was carried o...

Collecting weed exact counts in an agricultural field is easy but extremely time consuming. Image analysis algorithms for object extraction applied to pictures of agricultural fields may be used to estimate the weed content with a high resolution (≈ 1m), and pictures acquired at a large number of sites can be used to get maps of weed contents over a whole field at a reasonably low cost. However...

a field study was conducted to determine the effects of planting method, density and nicosulforon on corn (ksc704) and weeds grown in corn at agricultural and natural resources research center of khorasan-razavi province, iran in 2009-2010 growing season. the treatments were: three planting methods (one row, two row and in-row), two planting density (75000 and 90000 plants/ha) and three doses o...

Six field trials were conducted over three growing seasons to evaluate both pre-and post-emergence applications of the recently developed herbicide mesotrione, for weed control in maize. As a pre-emergence treatment it provided excellent control of broadleaf weeds (>99% reduction in dry matter) but was poor on grass weeds (ca 80% reduction). However, its combination with atrazine, s-metolachlor...

Crops that have been genetically modified (GM) to be tolerant to herbicides have been widely grown in the USA since 1996. The rapid and widespread adoption of this technology reflects the important economic and environmental benefits that farmers have derived from its use (equal to $21.7 billion additional farm income and a 225 million kg reduction in herbicide active ingredient use 1996-2012)....