in order to determine the critical period of weed control and investigation the effect of periodical control and interference of weeds natural population on yield and yield components of winter canola (brassica napus l. cv. okapi) in west region of tehran an experiment was carried out at research field of tarbiat modarres university, tehran, iran on 2004-5 growing season. fourteen experimental ...

Loblolly pine (Pin1r.s tae(/(i L.) seedlings were grown in co~npetition with native weeds using soil and seed bank collected from recently chopped and burned areas near Appornattox, Virginia. One-year-old seedlings were planted and weeds allowed to germinate from the native seed bank while being exposed to COz (ambient and elevated approximately 700 ppm) and water (water stressed and well water...

Weed management is a major issue in organic farming systems. Although interseeding cover crops is one alternative to herbicides, cover crops often suppress not only weeds but also main crops. Therefore, using cover crops for weed control without adverse effects on main crop growth is important. To verify the effect of cover crops on competition between main crops, cover crops and weeds in snowy...

The rust fungus Maravalia cryptostegiae, from south-west Madagascar, was introduced into Australia in 1995 as a classical biological control agent against the highly invasive rubber-vine weed Cryptostegia grandiflora, a woody climber endemic to Madagascar. The rust was released at 69 sites between 1995 and 1997 and is now established throughout the plant’s exotic range in Queensland, estimated ...

Uncontrolled weeds cause considerable losses in the grain yield of pigeonpea. Field experiments were conducted for seven years from 1998 to 2004 on a loamy sand soil to study the effect of weed management on weeds, growth and grain yield of pigeonpea. In some years, weed dry matter was higher than in others, due to variation in rainfall received. Two hand weedings, pendimethalin in integration ...

Phytotoxic Activity of the 6-acetyl-5-hydroxy-2isopropenyl-2,3-dihydrobenzofurane (1) isolated from Trichocline reptans (Asteraceae) was investigated in two weed species. Results indicate that the best growth inhibition effect ocurres on Chenopodium album weed. Phythotoxic effect of the T. reptans chloroformic extract and of the benzofurane are discussed and compared in the two weed species. In...

Loblolly pine (Pinus taeda L.) seedlings were grown in competition with native weeds using soil and seed bank collected from recently chopped and burned areas near Appomattox, Virginia. One-year-old seedlings were planted and weeds allowed to germinate from the native seed bank while being exposed to CO(2) (ambient and elevated - approximately 700 ppm) and water (water stressed and well watered...

this research was carried out for evaluation of competitive ability of some wheat cultivars (triticum aestivum l.) of recommended wheat in dargaz region with common weed of feral rye (secale cereale). experiment was conducted as factorial based on randomized complete block design with three replications in 2010-2011 growing season. experimental factors were included four wheat cultivars of says...

a field experiment was conducted in khorramabad to evaluate the efficacy of 12 herbicides [ethalfloralin (3 l.ha-1), trifloralin (2 l.ha-1), pendimethalin (1.5-2.5 l.ha-1), imazethapyr (0.5-0.7 l.ha-1), isoxaflotole (80 g.ha-1), pyridate (2.5 l.ha-1), bentazon (2 l.ha-1), metribuzine (0.7 kg.ha -1), fomesafen (1 l.ha-1), simazine (80 g.ha-1), prometrine (830 g.ha-1), haloxyfop-r-methyl (1 l.ha-...