Cabbage (B. oleracea L.) is an important vegetable crop in Florida. In 2010, Florida ranked third nationally in the production of fresh market cabbage accounting for 12.7% of the U.S. total cabbage production (USDA, 2017a). In 2016, cabbage growers in Florida planted 3439 ha fresh market cabbage and harvested 3197 ha, and the average yield was 36,980 kg·ha−1 (USDA, 2017b). Cabbage produced in Florida is exclusively for fresh market with the late fall, winter, and early spring harvests supplying the northern United States (USDA, 2017b).
In Florida, cabbage is typically grown without a plastic mulch and as a result, weeds are a significant problem in most fields. Weed competition may reduce cabbage growth, quality, and yield by competing for nutrients, sunlight, and soil moisture (Al-Khatib et al., 1995; Bhowmik and McGlew, 1986; Hoyt et al., 1996; Webster, 2010). The most common weeds in Florida cabbage production during the peak production period (December through February) are winter annuals such as cutleaf evening primrose (Oenothera laciniata Hill.) and wild radish (Raphanus raphanistrum L). However, in late fall or near the end of harvest in early spring, summer annual broadleaf weeds, such as common lambsquarters (Chenopodium album L.), and annual grass species, such as crabgrass (Digitaria spp.) and goosegrass [Eleusine indica (L.) Gaertn.], can be problematic. Yellow (Cyperus esculentus L.) and purple (Cyperus rotundus L.) nutsedges are also a serious issue. Because of its small stature, shallow root system, and thin canopy, cabbage seedlings are poor competitors with weeds. Therefore, controlling weeds early in the season is particularly important to maintain crop vigor and yield (Miller and Hopen, 1991; Weaver, 1984).
As with most minor crops, registered herbicides for use in cabbage are limited. Bensulide, clomazone, DCPA, oxyfluorfen, and trifluralin are registered for preplant incorporated application (Zotarelli et al., 2016). Clethodim, clopyralid, DCPA, napropamide, and sethoxydim are registered for over-the-top applications (Zotarelli et al., 2016). S-metolachlor controls annual broadleaf and grass weeds and suppress nutsedge species (Anonymous, 2014; Bellinder et al., 1989; Sikkema et al., 2007). It is registered with a third-party identified label in Florida, and growers need to sign an agreement with the third-party indemnitors. The field half-life of S-metolachlor is generally 15–25 d based on direct bioassay measurements in southern states (Shaner, 2014). Now, most cabbage growers in Florida use a single application of S-metolachlor immediately after transplant for weed control. However, a single application typically does not provide season-long weed control.
There are few published studies evaluating weed control and cabbage tolerance of herbicides applied PRE-T or POST-T over the top. The objectives of this research were to evaluate weed control and cabbage tolerance to multiple herbicide programs.
Al-Khatib, K., Libbey, C. & Kadir, S. 1995 Broadleaf weed control and cabbage seed yield following herbicide application HortScience 30 1211 1214
Anonymous, 2014 Dual II magnum. Syngenta Crop Protection, LLC, Greensboro, NC
Bellinder, R., Wilcox-Lee, D., Senesac, A. & Warholic, D. 1989 Response of early-maturing cabbage (Brassica oleracea var. capitata) to metolachlor Weed Technol. 3 463 466
Bhowmik, P.C. & McGlew, E.N. 1986 Effects of oxyfluorfen as a pretransplant treatment on weed control and cabbage yield J. Amer. Soc. Hort. Sci. 111 686 689
Choi, J., Fermanian, T., Wehner, D.J. & Spomer, L. 1988 Effect of temperature, moisture, and soil texture on DCPA degradation Agron. J. 80 108 113
Das, A.C., Debnath, A. & Mukherjee, D. 2003 Effect of the herbicides oxadiazon and oxyfluorfen on phosphates solubilizing microorganisms and their persistence in rice fields Chemosphere 53 217 221
Hopen, H.J., Hughes, R.L. & Michaelis, B.A. 1993 Selectivity among cabbage (Brassica oleracea L.) cultivars by clomazone Weed Technol. 7 471 477
Hoyt, G.D., Bonanno, A.R. & Parker, G.C. 1996 Influence of herbicides and tillage on weed control, yield, and quality of cabbage (Brassica oleracea L. var. capitata) Weed Technol. 10 50 54
Loux, M.M., Liebl, R.A. & Slife, F.W. 1989 Availability and persistence of imazaquin, imazethapyr, and clomazone in soil Weed Sci. 37 259 267
Miller, A.B. & Hopen, H.J. 1991 Critical weed-control period in seeded cabbage (Brassica oleracea var capitata) Weed Technol. 5 852 857
O’barr, J.H., McCauley, G.N., Bovey, R.W., Senseman, S.A. & Chandler, J.M. 2007 Rice response to clomazone as influenced by application rate, soil type, and planting date Weed Technol. 21 199 205
Shaner, D.L. 2014 Herbicide handbook. 10th ed., p. 110, 134, 320, 406. In: K.S. Lawrence (ed.). Weed Sci. Soc. America, Lawrence, KS
Sikkema, P.H., Soltani, N., Deen, W. & Robinson, D.E. 2007 Effect of S-metolachlor application timing on cabbage tolerance Crop Prot. 26 1755 1758
USDA 2017a Cabbage statistics, United States Department of Agriculture, Economics, Statistics and Market Information System. 12 June 2017. <http://usda.mannlib.cornell.edu/MannUsda/ viewDocumentInfo.do?documentID=1397>.
USDA 2017b Cabbage statistics, United States Department of Agriculture, National Agricultural Statistics Service. 20 May 2017. <https://quickstats.nass.usda.gov>.
Weaver, S.E. 1984 Critical period of weed competition in three vegetable crops in relation to management practices Weed Res. 24 317 325
Webster, T. 2010 Weed survey-southern states: cucurbits, fruiting vegetables, cole crops and greens, other vegetables, peaches, apples, fruits and nuts, citrus crops Proc. South Weed Sci. Soc. 63 250
Zotarelli, L., Dittmar, P.J., Ozores-Hampton, M.O., Dufault, N.S., Stansley, P., Smith, H.A., Webb, S.E., Wang, Q. & Miller, C. 2016. Cole crop production. p. 33–51. In: G. Vallad, J. Freeman, and P. Dittmar (eds.). Vegetable production handbook for Florida 2016–2017. Univ. Florida’s Inst. Food Agr. Sci., Gainesville, FL.