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Tolerance and Suppression of Weeds Varies among Carrot Varieties

  • Jed B. Colquhoun (a1), Richard A. Rittmeyer (a1) and Daniel J. Heider (a1)


Slow carrot emergence and canopy development render the crop a poor competitor with weeds. In this study, the ability to suppress weeds and maintain yield in the presence of weeds was compared among nine carrot varieties that included those selected by plant breeders for rapid vegetative canopy development compared to traditional varieties. Two weed management treatments were compared: handweeding for 21 d after carrot seeding versus handweeding for the entire carrot season. In years and locations with low to moderate weed pressure, such as in the 2014 study, differences among carrot varieties in weed competitiveness or tolerance were less apparent and therefore less relevant. Maximum carrot yield loss to weed competition among varieties was 28% in 2014. Yield loss in the presence of weeds was 15% or less with six of the nine carrot varieties. However, when weed pressure was intense in the 2015 study, both carrot plant density and carrot canopy development were inversely related to weed biomass. Carrot yield loss in the presence of weeds ranged from 38 to 87%. Despite correcting seeding populations for differences in germination among carrot varieties, carrot stand establishment varied greatly and would likely affect subsequent weed control measures such as timely cultivation or herbicide application. Future research efforts are warranted that consider carrot stand establishment factors and their relationship with integrated weed management programs.


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Associate Editor for this paper: Peter J. Dittmar, University of Florida.



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Begna, SH, Hamilton, RI, Dwyer, LM, Stewart, DW, Cloutier, D, Assemat, L, Foroutan-pour, K, Smith, DL (2001) Weed biomass production response to plant spacing and corn (Zea mays) hybrids differing in canopy architecture. Weed Technol 15:647653
Bussan, A, Burnside, O, Orf, J, Ristau, E, Puettmann, K (1997) Field evaluation of soybean (Glycine max) genotypes for weed competitiveness. Weed Sci 45:3137
Callaway, M (1992) A compendium of crop varietal tolerance to weeds. Am J Altern Agric 7:169180
Colquhoun, J, Gevens, A, Groves, R, Heider, D, Jensen, B, Nice, G, Ruark, M (2016). Commercial Vegetable Production in Wisconsin. UW-Extension Bulletin A3422. Accessed February 24, 2016
Didon, UME (2002) Variation between barley cultivars in early response to weed competition. J Agron Crop Sci 188:176184
Heap, I (2016). The International Survey of Herbicide Resistant Weeds. Accessed June 13, 2016
Jordan, M (1993) Prospects for weed control through crop interference. Ecol Appl 3:8491
Lindquist, JL, Mortensen, DA (1998) Tolerance and velvetleaf (Abutilon theophrasti) suppressive ability of two old and two modern corn (Zea mays) hybrids. Weed Sci 46:569574
Soares, I, Freitas, F, Negreiros, M, Freire, G, Aroucha, E, Grangeiro, L, Lopes, W, Dombroski, J (2010) Weed interference in carrot yield and quality. Planta Daninha 28:247254
Swanton, CJ, O’Sullivan, J, Robinson, DE (2010) The critical weed-free period in carrot. Weed Sci 58:229233
Traore, S, Lindquist, JL, Mason, SC, Martin, AR, Mortensen, DA (2002) Comparative ecophysiology of grain sorghum and Abutilon theophrasti in monoculture and in mixture. Weed Res 42:6575
Vandeleur, RK, Gill, GS (2004) The impact of plant breeding on the grain yield and competitive ability of wheat in Australia. Aust J Agric Res 55:855861
William, R, Warren, G (1975) Competition between purple nutsedge and vegetables. Weed Sci 23:317323
Williams, M, Boydston, R (2006) Volunteer potato interference in carrot. Weed Sci 65:9499


Tolerance and Suppression of Weeds Varies among Carrot Varieties

  • Jed B. Colquhoun (a1), Richard A. Rittmeyer (a1) and Daniel J. Heider (a1)


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