abstract leaving crop residues on the soil surface may significantly affect the behavior and activity of herbicides. to probe this effect, a factorial experiment in a randomized complete block design with three replications was conducted using two factors including different rates of wheat surface residue (0, 1250, 2500 and 3750 kg ha-1 ) and different rates of trifluralin (%48 ec) herbicide (7...

a two year field experiment was carried out to evaluate the effects of municipal waste compost (c), composted cattle manure (m), and nitrogen (n) on growth and composition of weeds in a corn field in shiraz using a split-split plot design with 3 replicates. visual inspection of the plots showed that the manure treatments neither introduced new weed species nor increased weed density more than t...

The compositions of the germinable weed seedbank and aboveground weed communities in a long-term tillage and rotation study were characterized 4, 5, and 6 yr (2002 to 2004) after the adoption of glyphosate-tolerant corn and soybean. Averaged across rotation, mean germinable weed seed density and diversity were greatest in the no-tillage treatment as compared to the minimumand conventional-tilla...

Fertilizer amendments can impact weed populations in a variety of ways. This study evaluated the effects of 12 year-long applications of different fertilization systems on size and composition of the weed seed bank in a conventionally managed maize monoculture field. Fertilization systems included all factorial combinations of two dairy cattle slurry rates, three vegetable, fruit and garden was...

We investigated the effects of organic and conventional pest and fertility management on weed cover and the seed bank community in an organic rotation. The study was conducted during the 4th and 5th years of an organic rotation on part of a long term organic-conventional comparison trial. Results showed that although crop type (potato vs. cabbage) in a single year significantly affected wee...

Field experiments were conducted to study weed population shifts in long-term conservation tillage systems. The objectives of this study were to determine weed community abundance, diversity and composition on conventional tillage (CT), minimum tillage (MT), no-tillage with paraplow (ZT) and no-tillage (NT) systems, and to identify species that are associated with specific tillage systems. The ...

the aim of this study was to evaluate the effect of long-term reduced tillage on yield and weeds of spring barley. treatments consisted of three tillage systems including: (a) conventional tillage (ct), (b) reduced tillage (rt), and (c) herbicide tillage (ht) as the main plot, and two cultivars of spring barley (tocada and rastik) as subplots. the results showed that the yield of both cultivars...

Arable land weed seed banks are dynamic and reflect cropping history, current management, and environment. Changes in crop rotation and tillage system can alter weed seed density and species composition. In the semi-arid region of the Pacific Northwest, USA, no-till spring cropping is being studied as an alternative to the traditional winter wheat (Triticum aestivum L.)/dust-mulch fallow (WWF) ...

A study was carried out to determine the composition and predominance of weed species in wheat field in Khokana of Kathmandu valley as a representative sample of mountain ecosystem in Nepal. A total of 44 weed species representing 18 families were recorded. The most abundant species were Chenopodium album, Polygonum plebeium and Spergula arvensis. With the improved temperature after February, t...

This research compared effects of the weed control practice, soil cultivation, and the conventional practice, glyphosate application on weed seedbank, in a vineyard system. The experiment was conducted in a commercial wine-grape vineyard in the Napa Valley of northern California from 2003 to 2005. The annual treatments were ‘‘winter–spring glyphosate,’’ ‘‘spring cultivation,’’ ‘‘fall–spring cul...