Yellow Nutsedge ( Cyperus esculentus ) Competition with Cotton ( Gossypium hirsutum )

Studies were conducted at the University of Florida, West Florida Research and Education Center to determine the effect of glyphosate on purple nutsedge control and nutsedge tuber production when glyphosate was applied to the same plots over 3 y in glyphosate-resistant soybean and cotton. Greater than 90% control of purple nutsedge foliage was achieved with a single POST application of glyphosate at 0.9 kg ai/ha in soybean or a sequential glyphosate application of 1.1 kg/ha POST followed by 0.6 kg/ha POST-directed in cotton. By the end of the third year of the study, these same treatments reduced purple nutsedge tuber density to less than 0.2% of the nontreated. In cotton, cultivation alone reduced tuber numbers by greater than 90%. Viability of tubers was also reduced by 80% in soybean and by 65% in cotton in the glyphosate-treated plots. Comparison treatments of imazaquin PRE followed by imazaquin POST in soybean or norflurazon PRE followed by cyanazine plus MSMA POST-directed in cotton also reduced purple nutsedge tuber density by ≥85% after three consecutive years of treatment.

Section: Resultsmentioning

confidence: 96%

Purple Nutsedge (Cyperus rotundus) Control with Glyphosate in Soybean and Cotton¹

Edenfield¹,

Brecke²,

Colvin³

et al. 2005

“…Peanut yields sometimes do not reflect the levels of weed control, especially if annual grass and broadleaf weeds are controlled (Grichar 1995;Grichar and Boswell 1989;Wilcut 1991). Also, Patterson et al (1980) and Johnson and Mullinix (1997) reported that yellow nutsedge was not as competitive with cotton (Gossypium hirsutum L.) as many annual weeds.…”

Section: Resultsmentioning

confidence: 99%

S-Metolachlor Compared with Metolachlor on Yellow Nutsedge (Cyperus esculentus) and Peanut (Arachis hypogaea)¹

Grichar¹,

Lemon²,

Brewer³

et al. 2001

S-metolachlor was compared with metolachlor at four field locations in Texas during the 1996 and 1997 growing seasons in terms of yellow nutsedge control, peanut injury, and peanut yield. S-metolachlor caused peanut injury comparable to metolachlor when either herbicide was applied preplant incorporated or preemergence. Yellow nutsedge control was similar and peanut yields were comparable with the two herbicides. At one location where yellow nutsedge failed to develop, the untreated check produced one of the highest yields.

“…Seed cotton yields were reduced 18 kg/ha for every yellow nutsedge plant per square meter in Alabama (Patterson et al 1980). Season-long competition with yellow nutsedge reduced cotton yields by 34% in another study (Keeley and Thullen 1975).…”

Section: Weedinessmentioning

confidence: 91%

Yellow Nutsedge Cyperus esculentus L.—Snack Food of the Gods¹

Defelice¹

2002

No more the grassy brook reflects the day, But, chocked with sedges, works its weedy way; The Deserted Village, Oliver Goldsmith, 1770. Yellow nutsedge (Cyperus esculentus L.) is a perennial herbaceous sedge native to the eastern Mediterranean (Mabberley 1997; Tutin et al. 1980; Zeven and Zhukovsky 1975). Cultivated in ancient Egypt for its tasty and oil-rich tubers, the wild type has spread as a weed to all the continents of the world and adapted to climates from tropical to subarctic. Adaptability to many agricultural habitats and the great reproductive capacity of yellow nutsedge have propelled it to rank as the 16th worst weed in the world (Holm et al. 1991a, 1991b; Negbi 1992).