The widespread occurrence of herbicide-resistant (HR) Kochia scoparia is an increasing concern for growers in the US Great Plains and Canada. K. scoparia populations resistant to dicamba have been reported in six US states. Populations cross-resistant to dicamba and fluroxypyr have been reported from wheat fields in Montana, USA. It is unclear whether resistance to the auxinic herbicides (dicam...

Evaluation of the viable seeds in a soil, otherwise known as the seed pool or seed bank, is a crucial component of many weed dynamic and plant ecology studies. Seed bank estimation is used to predict the possibility of future weed infestations in rangelands as well as the nascent native plant diversity within them. However, there is no standardized method of reporting seed bank evaluation techn...

Experiments were conducted to determine whether the beet leafhopper, Circulifer tenellus (Baker) (Hemiptera: Cicadellidae), transmits the purple top phytoplasma to potato, Solanum tuberosum L.; beets, Beta vulgaris L.; and selected weed hosts. The beet leafhopper-transmitted virescence agent (BLTVA) phytoplasma was identified as the causal agent of the potato purple top disease outbreaks that r...

We crossed the C3 species Atriplex prostrata with the C4 species Atriplex rosea to produce F1 and F2 hybrids. All hybrids exhibited C3-like δ(13)C values, and had reduced rates of net CO2 assimilation compared with A. prostrata. The activities of the major C4 cycle enzymes PEP carboxylase, NAD-malic enzyme, and pyruvate-Pi dikinase in the hybrids were at most 36% of the C4 values. These results...

soil salinity threat for agricultural ecosystems in many parts of iran, and negatively affects crop production. in order to examine salinity tolerance of kochia a series of experiments were conducted in crd with four replications, seven levels of salinity (0, 10, 20, 30, 40, 50 and 60 ds.m-1), two growth stages (planting and early seedling) and interval irrigation. result showed that decrease o...

Long-term no-till (NT) systems in the semiarid central Great Plains of United States require flexible management strategies to minimize impacts herbicide resistant (HR) kochia (Kochia scoparia L.) and tumble windmill grass (Chloris verticillata Nutt.) as well nutrient stratification on soil crop productivity. This study examined strategic tillage (ST) control HR weeds improve yields an otherwis...