Beet armyworm, Spodoptera exigua (Hübner), oviposition preferences were determined on Þve host plants: cabbage (Brassica oleracea capitata L.), cotton (Gossypium hirsutum L.), bell pepper (Capsicum annuum L.), pigweed (Amaranthus retroflexus L.), and sunßower (Helianthus annuus L.) in no-choice, two-choice, and Þve-choice tests. Tests were conducted in the laboratory, greenhouse, and Þeld cages...

in order to study the effects of co2 enrichment on growth and competitiveness of soybean (glycine max) and millet (panicum miliaceum) against redroot pigweed (amaranthus retroflexus) and lambsquarter (chenopodium albam) an experiment was conducted using two co2 concentrations (350 and 700 ppm). for evaluating effects of co2 variation on inter-and intra-specific competition plants were grown in ...

to study the effect of different weed control methods in tomato, an experiment was conducted as completely randomized block design with three replications at the research farm of university of tehran (karaj) in 2008. the treatments consisted of post emergence (at recommended rate) or pre emergence (reduced rate in combination with mulch) application of metribuzin, rimsulfuron and sulfosulfuron,...

Soltani, N., Vyn, R. J., Van Eerd, L. L., Shropshire, C. and Sikkema, P. H. 2009. Effect of reduced herbicide rates on weed control, environmental impact and profitability of corn. Can. J. Plant Sci. 89: 969 975. A study was conducted over a 3-yr period (2003, 2004, and 2005) to evaluate the effect of reduced herbicide rates 20, 40, 60, 80, and 100% of the manufacturer’s recommended rate (MRR) ...

The influence of weed seed predation by invertebrates and vertebrates was examined in relation to distance from hedgerows in maize fields of southwestern Michigan. Experiments were conducted in spring and winter and included five common weed species, i.e., velvet-leaf (Abutilon theophrasti), redroot pigweed (Amaranthus retroflexus), common lamb's-quarters (Chenopodium album), fall panicum (Pani...

Experiments were conducted in the greenhouse to assess root galling and egg production of three root-knot nematode species, Meloidogyne arenaria, M. incognita, and M. javanica, on several weeds common to Florida agricultural land. Weeds evaluated were Amaranthus retroflexus (redroot pigweed), Cyperus esculentus (yellow nutsedge), Eleusine indica (goosegrass), Portulaca oleracea (common purslane...

Sarmentine, 1-(1-pyrrolidinyl)-(2E,4E)-2,4-decadien-1-one, is a natural amide isolated from the fruits of Piper species. The compound has a number of interesting biological properties, including its broad-spectrum activity on weeds as a contact herbicide. Initial studies highlighted a similarity in response between plants treated with sarmentine and herbicidal soaps such as pelargonic acid (non...

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 ...

In anaerobic soil disinfestation (ASD), amended with a carbon source undergoes conditions accompanied by changes in microbial community composition and an increase the concentration of organic acids, primarily acetic butyric gases that are deleterious to plant pathogens, insects, potentially weeds. The purpose this study was explore efficacy ASD different sources on inactivation propagules vari...

We reviewed the timing of peak rate emergence for 15 problematic weed species as well ways to use this knowledge improve control. Much previous literature modeled based on growing-degree-days. For these models, we input average temperature data from several zones Northeast USA. Within species, model-predicted in warmest and coolest differed by an 39 days. Also within there was some variation be...