Herbicide resistant weed populations have developed due to the repeated application of herbicides. Elevated concentrations of atmospheric CO2 can have positive effects on weed growth, but how rising CO2 might affect herbicide resistant weeds is not known. Ragweed (Ambrosia artemisiifolia L.) ecotypes known to be resistant or susceptible to glyphosate herbicide were exposed to either ambient or ...

this experiment was conducted for three consecutive years from 2000 to 2002 to evaluate the effects of integrated weed management on weeds of alfalfa at the safi abad agricultural research farm of dezful. the experimental design was a randomized complete block with strip-split plot arrangement of treatments. herbicide treatment was as horizontal factor at five levels which in 2000, consisted of...

Application of 4-amino-3,5,6-trichloropicolinic acid (picloram) to roots stimulated the production of ethylene in both mesquite [Prosopis juliflora (Swartz) DC. var. glandulosa (Torr.) Cockerell] and huisache [Acacia farnesiana (L.) Willd.] seedlings. Herbicide levels rose in tissues before we detected increased ethylene production. Rates of ethylene production by various parts of the plant par...

Tradescantia 4430 clone stamen hair mutation (Trad-SHM) bioassay was used to evaluate the genotoxicity of a herbicide composed of triazines (atrazine and simazine) after in situ exposure. Thirty plant pots were exposed during the herbicide application (test group) and a control group was maintained in a greenhouse (control group). Genotoxicity was expressed in terms of pink mutation events (EMP...

After cultural treatments such as site preparation, release and fertilization, changes in the supply of mineral nutrients relative to each other and shifts in the composition of vegetation may have a delayed effect on the nutrition, carbon partitioning and growth of forest trees. This study was conducted to evaluate the influence of early management options that control vegetation and fertility...

Most agronomic situations involve a sequence of herbicide, fungicide, and insecticide application. On the other hand, use of pesticidal combinations has become a standard practice in the production of many agricultural crops. One of the most important processes influencing the behavior of a pesticide in the environment is its degradation in soil. It is known that due to several pesticide applic...

The present study was undertaken to determine the persistence of acetochlor under real field conditions at maize crop. The chloroacetanilide herbicide acetochlor was applied as a pre-emergent spray on maize crop at 3 days after sowing in the experimental field in Didactical Station Ezăreni. The herbicide acetochlor was identified and quantified from soil and maize plants based on accelerated so...

The Farm Scale Evaluations of genetically modified herbicide-tolerant crops (GMHT) were conducted in the UK from 2000 to 2002 on beet (sugar and fodder), spring oilseed rape and forage maize. The management of the crops studied is described and compared with current conventional commercial practice. The distribution of field sites adequately represented the areas currently growing these crops, ...

Exotic annual grasses are a major challenge to successful restoration in temperate and Mediterranean climates. Experiments to restore abandoned agricultural fields from exotic grassland to coastal sage scrub habitat were conducted over two years in southern California, U.S.A. Grass control methods were tested in 5 m2 plots using soil and vegetation treatments seeded with a mix of natives. The t...

A major issue in the modelling of weed resistance to herbicide lies in effectively handling the wild dynamics, that is, the allele frequency prior to the herbicide application, and in particular when starting to use the herbicide. The wild allele frequency is a key variable as the resistance evolution is highly sensitive to it, moreover it is extremely difficult to measure in the agricultural f...