Translator Disclaimer
1 January 2012 Yellow Nutsedge (Cyperus esculentus) Growth and Tuber Production in Response to Increasing Glyphosate Rates and Selected Adjuvants
Joel Felix, Joseph T. Dauer, Andrew G. Hulting, Carol Mallory-Smith
Author Affiliations +
Abstract

Greenhouse studies were conducted to evaluate the influence of selected adjuvants on glyphosate efficacy on yellow nutsedge and tuber production. Glyphosate was applied at 0, 0.25, 0.43, 0.87, 1.26 (1× rate), and 1.74 kg ae ha−1 at 31 d after yellow nutsedge was planted. Each rate was mixed with one of the following adjuvants: ammonium sulfate (AMS), AMS plus nonionic surfactant (NIS), or AMS plus an experimental adjuvant (W-7995) plus NIS. Plants were evaluated for injury and for the number and size of tubers produced. Dose–response curves based on log-logistic models were used to determine the effective glyphosate rate plus adjuvant that provided both 90% effective dose (ED90) for yellow nutsedge injury and reduced tuber production. Addition of NIS to glyphosate plus AMS resulted in the greatest yellow nutsedge injury at 28 d after treatment (DAT). Addition of the experimental adjuvant plus NIS resulted in injury similar to NIS alone. The ED90 for injury at 28 DAT was 2.12 kg ha−1 with glyphosate plus AMS and NIS compared with 2.18 kg ha−1 for W-7995 plus NIS and 3.06 kg ha−1 with AMS alone. The ED90 rates with different adjuvants represent 168%, 173%, and 243% of the highest glyphosate rate (1.26 kg ha−1) labeled for application on many glyphosate-resistant crops. However, the estimated ED90 to reduce small, medium, large, and total tubers were 1.60, 1.50, 1.63, and 1.66 kg ha−1, respectively. Increases in labeled rates of glyphosate may be required to reduce yellow nutsedge tuber production in field conditions. Use of lower glyphosate rates should be discouraged because it may increase tuber production and exacerbate yellow nutsedge expansion in infested fields.

Nomenclature: Glyphosate; yellow nutsedge, Cyperus esculentus L. CYPES.

Weed Science Society of America
Joel Felix, Joseph T. Dauer, Andrew G. Hulting, and Carol Mallory-Smith "Yellow Nutsedge (Cyperus esculentus) Growth and Tuber Production in Response to Increasing Glyphosate Rates and Selected Adjuvants," Weed Technology 26(1), 95-101, (1 January 2012). https://doi.org/10.1614/WT-D-11-00066.1
Received: 13 May 2011; Accepted: 1 September 2011; Published: 1 January 2012
JOURNAL ARTICLE
7 PAGES


Share
SHARE
KEYWORDS
adjuvants
furrow irrigated systems
yellow nutsedge tubers
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top