Redroot pigweed is one of the injurious agricultural weeds on a worldwide basis. Understanding of its interference impact in crop field will provide useful information for weed control programs. The effects of redroot pigweed on cotton at densities of 0, 0.125, 0.25, 0.5, 1, 2, 4, and 8 plants m(-1) of row were evaluated in field experiments conducted in 2013 and 2014 at Institute of Cotton Res...

Weed control by crops through growth suppressive root exudates is a promising alternative to herbicides. Buckwheat (Fagopyrum esculentum) is known for its weed suppression and redroot pigweed (Amaranthus retroflexus) control is probably partly due to allelopathic root exudates. This work studies whether other weeds are also suppressed by buckwheat and if the presence of weeds is necessary to in...

Weedy Amaranthus species frequently cause economically significant reductions in crop yields. Accurate identification of Amaranthus species is important for efficient weed control, but Amaranthus species can interbreed, which might cause difficulty when identifying hybrid-derived specimens. To determine which of several economically important weedy Amaranthus species are most genetically simila...

Consumption rates, development times, and life table parameters of the beet armyworm, Spodoptera exigua (Hübner), 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. Mean total leaf weight consumed by larvae was highest in cabbage (2.7 g) ...

INTRODUCTION The prevalence of atopic diseases has increased in recent decades dramatically. The most common aeroallergens in Northeastern Iran have not been fully defined. Determining the most common aeroallergens in allergic patients based on the skin prick test (SPT) was aimed in this investigation. MATERIALS AND METHODS This cross-sectional study enrolled 1,006 allergic patients (aged 1-8...

Weeds are a major problem in seeding rangeland and cropland to native grasses. However, many immature weedy forbs and grasses are palatable to cattle. Research was conducted using yearling cattle for weed control in big bluestem (Andropogon gerardii var. gerardii Vitman) seedings (1987, 1988) at Mead, Nebraska on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudoll) soil....

Hairy vetch is a leguminous winter annual cover crop that provides a significant contribution toward meeting the nitrogen requirement of succeeding crops. Hairy vetch residue is capable of suppressing weeds, but low levels of residue can intermittently stimulate the emergence of weeds, particularly smooth pigweed. This research was conducted to assess the inhibitory and stimulatory effects of h...

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...

Few weed species have gained so much attention over the past decade as waterhemp. Waterhemp has gone from an obscure weed species in the 1980s to a species that has achieved widespread distinction throughout most of the Midwest. This species gained its notoriety in the early 1990s when it began appearing in many corn and soybean fields in Illinois, Iowa, Kansas, and Missouri. In these fields AL...

The chemical interaction between plants, which is referred to as allelopathy, may result in the inhibition of plant growth and development. The objective of this research was to determine the impact of kenaf (Hibiscus cannabinus L.) plant extracts on the seed germination of five plant species. Four concentrations (0, 16.7, 33.3 and 66.7 g/L) of kenaf leaf, bark, and core extracts were applied t...