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Interactions among Cultivation, Weeds, and a Biofungicide in Organic Vidalia® Sweet Onion

Published online by Cambridge University Press:  11 September 2017

W. Carroll Johnson III ,
Bhabesh Dutta ,
F. Hunt Sanders Jr.  and
Xuelin Luo
W. Carroll Johnson III*
Affiliation:
Research Agronomist, USDA-ARS, Tifton Campus, P.O. Box 748, Tifton, GA 31793-0748
Bhabesh Dutta
Affiliation:
Assistant Professor and Former Disease Management Specialist, Department of Plant Pathology, University of Georgia, Tifton Campus, Tifton, GA 31793
F. Hunt Sanders Jr.
Affiliation:
Assistant Professor and Former Disease Management Specialist, Department of Plant Pathology, University of Georgia, Tifton Campus, Tifton, GA 31793
Xuelin Luo
Affiliation:
Research Statistician, University of Georgia, Tifton Campus, Tifton, GA 31793
*
*Corresponding author’s E-mail: Carroll.Johnson@ars.usda.gov
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Abstract

Weed management in the organic Vidalia® sweet onion production system is largely dependent on multiple cultivations with a tine weeder. Earlier research suggested cultivation with a tine weeder did not predispose onion bulbs to infection during storage. Trials were conducted from 2012 through 2014 near Lyons, GA, to determine the interactive effects of cultivation, weed removal, and a biofungicide on weed densities, onion yield, grade, and diseases of stored onion. Cultivation twice or four times at biweekly intervals with a tine weeder reduced densities of cutleaf evening-primrose, lesser swinecress, and henbit compared with the noncultivated control, although weeds surviving cultivation were very large and mature at harvest. Cultivation generally improved onion yields over the noncultivated control, except in 2014, when baseline weed densities were high and weeds surviving cultivation were numerous. Weeds removed by hand weeding improved onion yields, but that effect was independent of cultivation. Four applications of a biofungicide derived from giant knotweed had no effect on onion yield. Cultivation had no effect on incidence of the fungal disease botrytis neck rot, with inconsistent effects on the bacterial diseases center rot and sour skin. Weed removal with hand weeding did not affect diseases of stored onion. The biofungicide had no effect on diseases of stored onion. These results demonstrate the limitations of cultivation when cool-season weed infestations are dense. With no interactions among main effects, weed control and onion yield response to cultivation and hand weeding are independent. Cultivation for weed control is much less costly than hand weeding. With no interaction between the cultivation and weed removal main effects, it is not necessary to supplement tine weeder cultivation with costly hand weeding.

Keywords

Cutleaf evening-primrose, Oenothera laciniata Hillgiant knotweed, Reynoutria sachalinensis (F. Schm.) Nakaihenbit, Lamium amplexicaule Llesser swinecress, Coronopus didymus (L.) Sm.dry-bulb onion, Allium cepa L.Giant knotweed extractmechanical weed controlorganic weed controlReynoutria sachalinensis extracttine weeder
Type
Weed Management-Other Crops/Areas
Information
Weed Technology , Volume 31 , Issue 6 , December 2017 , pp. 890 - 896
Copyright
© Weed Science Society of America, 2017 

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Footnotes

a

Current address of third author: Field Market Development Specialist, Valent Biosciences, Tifton, GA 31794.

Associate Editor for this paper: Mark VanGessel, University of Delaware.

References

Literature Cited

Anonymous (2017) Regalia® specimen label. Davis, CA: Marrone Bio Innovations. http://marronebioinnovations.com/wp-content/uploads/2015/12/Regalia-Specimen-Label-REGSPE022.00.pdf. Accessed March 16, 2017Google Scholar
Ascard, J, Fogelberg, F (2008) Mechanical in-row weed control in transplanted and direct-sown bulb onions. Biol Agr Hort 25:235–251 CrossRefGoogle Scholar
Bond, W, Burston, S, Bevan, JR, Lennartsson, MEK (1998) Optimum weed removal timing in drilled salad onions and transplanted bulb onions grown in organic and conventional systems. Biol Agr Hort 16:191–201 CrossRefGoogle Scholar
Boyhan, GE, Hicks, RJ, Torrance, RL, Riner, CM, Hill, CR (2010) Evaluation of poultry litter and organic fertilizer rate and source for production of organic short-day onion. HortTechnology 20:304–307 CrossRefGoogle Scholar
Boyhan, GE, Kelley, WT (2008) Onion Production Guide. University of Georgia Extension Service Bulletin 198–2. 48 pGoogle Scholar
Boyhan, GE, Torrance, RL (2002) Vidalia onions—sweet onion production in southeastern Georgia. HortTechnology 12:196–202 CrossRefGoogle Scholar
Boyhan, GE, Torrance, RL, Cook, J, Riner, C, Hill, CR (2009) Plant population, transplant size, and variety effect on transplanted short-day onion production. HortTechnology 19:145–151 CrossRefGoogle Scholar
Johnson, WC III, Davis, JW (2014a) Effect of sprayer output volume and adjuvants on efficacy of clove oil for weed control in organic Vidalia® sweet onion. HortTechnology 24:428–432 CrossRefGoogle Scholar
Johnson, WC III, Davis, JW (2014b) Pelargonic acid for weed control in organic Vidalia® sweet onion production. HortTechnology 24:696–701 CrossRefGoogle Scholar
Johnson, WC III, Langston, DB Jr, MacLean, DD, Sanders, FH Jr, Torrance, RL, Davis, JW (2012) Integrated systems of weed management in organic transplanted Vidalia® sweet onion production. HortTechnology 22:64–69 CrossRefGoogle Scholar
Kurstjens, DA, Perdok, UD, Goense, D (2000) Selective uprooting by weed harrowing on sandy soils. Weed Res 40:431–447 CrossRefGoogle Scholar
Melander, B, Rasmussen, G (2001) Effects of cultural methods and physical weed control on intra-row weed numbers, manual weeding, and marketable yield in direct-sown leek and bulb onion. Weed Res 41:491–508 CrossRefGoogle Scholar
Melander, B, Rasmussen, IA, Barberi, P (2005) Integrating physical and cultural methods of weed control—examples from European research. Weed Sci 53:369–381 CrossRefGoogle Scholar
Su, H, Blair, R, Johnson, T, Marrone, P (2012) Regalia® bioprotectant in plant disease management. Outlooks on Pest Management 23:30–34 CrossRefGoogle Scholar
[USDA] U.S. Department of Agriculture (1995) United States Standards for Grades of Bermuda-Granex-Grano Type Onions. Washington, DC: USDA Google Scholar
[USDA] U.S. Department of Agriculture (2015) 2015 State Agriculture Overview—Georgia. USDA National Agricultural Statistics Service. https://www.nass.usda.gov/Quick_Stats/Ag_Overview/stateOverview.php?state=GEORGIA. Accessed March 14, 2017Google Scholar