abstract in order to determine the critical period of weed control in euro-flour variety of sunflower (helianthus annus, l.) an experimental was conducted with a randomized complete block design with 10 treatments and three replications in islamic azad university astara-branch-agricultural college in 2006 growing season. experimental treatments were conducted in two sets, the first set included...

In order to evaluate the impact of crop residues (zero, 25 and 50%) and nitrogen (zero, 125 and 250 kg ha) on weed seed bank and potato yield, two-years research was conducted as a split plot arranged in randomized complete block design in Rozveh Agriculture Research Station, Freidan-Esfahan. Numbers of weed species in seed bank, aboveground, and both seed bank and aboveground were 1, 2 and...

introduction: increasing crop competitive ability is an important part of integrated weed management (iwm). in this regard, identifying weeds reaction to soil fertility status for developing fertilizing methods, as components of iwm programs, is a necessity. materials and methods: in order to evaluate the growth characteristics of purple nutsedge under the conditions of interference with onion,...

a field experiment was conducted to investigate the spatial distribution of nutsedge (cyperus spp) during rice growing season using geostatic in 2011 at sari agricultural sciences and natural resources university. at the first field was divided into 36 grids (2.5×2.5 meter) after the final preparation. grid intersection points were determined and marked. all samples were taken from these points...

The beet armyworm, Spodoptera exigua (Hübner), is a sporadic but devastating secondary pest of cotton. Scouting cotton for egg masses is commonly recommended for identifying potential outbreaks and forproper timingof insecticide applications.However, there is disagreement regarding where to look on the plant for beet armyworm eggs. We investigated and quantiÞed placement of egg masses by labora...

this experiment was set to study the allelopatic effect of aqueous and alcoholic extracts of artemisia, coriander, eucalyptus and cumin on growth of red root pigweed and lambsquarters weeds at laboratory and field in the university of tehran (karaj-iran) in 2008. the herbal plant samples were ground and powdered for extraction preparation, and were mixed with distilled water in a beaker. the ex...

Recebido para publicação em 29/10/2008 Aceito para publicação em 16/5/2009 (003913) 1 Departamento de Nutrição, Faculdade de Saúde Pública, Universidade de São Paulo – USP, Av. Dr. Arnaldo, n. 715, CEP 01246-904, São Paulo – SP, Brazil, E-mail: [email protected] 2 Instituto do Coração (Heart Institute) (InCor), Faculdade de Medicina, Universidade de São Paulo – USP, São Paulo, SP, Brazil *A quem ...