HORTSCIENCE 53(5):646–650. 2018. https://doi.org/10.21273/HORTSCI12645-17 immediately after transplant for weed control. However, a single application typically does not provide season-long weed control. Evaluation of Herbicide Programs in There are few published studies evaluat- ing weed control and cabbage tolerance of Florida Cabbage Production herbicides applied PRE-T or POST-T over 1 the top. The objectives of this research were Jialin Yu and Nathan S. Boyd to evaluate weed control and cabbage toler- Horticultural Sciences Department, Gulf Coast Research and Education ance to multiple herbicide programs. Center, University of Florida, Wimauma, FL 33598 Materials and Methods Peter J. Dittmar Horticultural Sciences Department, 1233 Fifield Hall, University of Florida, Experiment description. Three field ex- Gainesville, FL 32611 periments were conducted from Nov. 2015 to Apr. 2016 in Balm (lat. 27.75 N, long. Additional index words. herbicide tolerance, pretransplanting, posttransplanting, sequential 82.26 W),Citra(lat.29.41 N, long. application, weed control 82.14 W), and Parrish, FL (lat. 27.58 N, Abstract Brassica oleracea long. 82.42 W). Soil at Balm, FL, was . In Florida, cabbage ( L.) is typically grown without a plastic Myakka series fine sand (sandy, siliceous, mulch and as a result, weeds are a significant problem in most fields. Experiments were and hyperthermic Aeric Alaquods) with 1.5% conducted from Nov. 2015 to Apr. 2016 in Balm, Citra, and Parrish, FL, to evaluate weed organic matter and a pH of 6.0. Soil at Citra control and ‘Bravo’ cabbage tolerance to multiple herbicide programs applied pre- was Hague sand (loamy, siliceous, semiac- transplanting (PRE-T), posttransplanting (POST-T), PRE-T followed by (fb) a sequential tive, and hyperthermic Arenic Hapludalfs) application at 3 weeks after transplanting (WATP), and POST-T fb sequential application with 0.8% organic matter and a pH of 6.5. at 3 WATP. PRE-T herbicide treatments of 277 g a.i./ha clomazone, 280 g a.i./ha oxyfluorfen, Soil at Parrish, FL, was Manatee series fine and 798 g a.i./ha pendimethalin and POST-T herbicide treatments of 6715 g a.i./ha dimethyl sand (coarse-loamy, siliceous, superactive, tetrachloroterephthalate (DCPA) were ineffective, and weed control never exceeded 70% in and hyperthermic Typic Argiaquolls) with Balm and provided <50% weed control in Citra and Parrish at 6 and 8 WATP, respectively. 1.2% organic matter and a pH of 6. POST-T applications of napropamide + S-metolachlor at 2242 + 1770 g a.i./ha, DCPA + + Cabbage ‘Bravo’ was transplanted on 20 S-metolachlor at 6715 1170 g a.i./ha, and S-metolachlor POST-T fb clopyralid at 1170 g a.i./ha Nov. 2015, 15 Dec. 2015, and 25 Nov. 2015 fb 210 g ae/ha were the most effective herbicide treatments and consistently provided in Balm, Citra, and Parrish, respectively, >70% weed control. In addition, results showed that all of the herbicide treatments when the transplants had four to five leaves. evaluated except the PRE application of clomazone at 277 g a.i./ha are safe for cabbage The plots were fertilized and irrigated with no adverse effect on yield. throughout the season as per industry stan- dards (Zotarelli et al., 2016). Plots consisted of a single raised bed 7.6-m long and 0.71-m Cabbage (B. oleracea L.) is an important raphanistrum L). However, in late fall or near wide with two rows of cabbage per bed. vegetable crop in Florida. In 2010, Florida the end of harvest in early spring, summer Plants were transplanted 38 cm apart in rows ranked third nationally in the production of annual broadleaf weeds, such as com- 20 cm apart. The principal broadleaf weeds fresh market cabbage accounting for 12.7% mon lambsquarters (Chenopodium album L.), were carpetweed (Mollugo verticillata L.), of the U.S. total cabbage production (USDA, and annual grass species, such as crabgrass cutleaf evening primrose, FL pusley (Richar- 2017a). In 2016, cabbage growers in Florida (Digitaria spp.) and goosegrass [Eleusine dia scabra L.), and wild radish in Balm; planted 3439 ha fresh market cabbage and indica (L.) Gaertn.], can be problematic. cudweed (Gamochaeta spp.), cutleaf evening harvested 3197 ha, and the average yield was Yellow (Cyperus esculentus L.) and purple primrose, FL pusley, and red sorrel (Rumex 36,980 kg·ha–1 (USDA, 2017b). Cabbage (Cyperus rotundus L.) nutsedges are also acetosella L.) in Citra; and cutleaf evening produced in Florida is exclusively for fresh a serious issue. Because of its small stature, primrose, common purslane (Portulaca oler- market with the late fall, winter, and early shallow root system, and thin canopy, cab- acea L.), and wild radish in Parrish. Goose- spring harvests supplying the northern United bage seedlings are poor competitors with grass and purple nutsedge were also present States (USDA, 2017b). weeds. Therefore, controlling weeds early in the experimental area in Citra and Parrish, In Florida, cabbage is typically grown in the season is particularly important to respectively. without a plastic mulch and as a result, weeds maintain crop vigor and yield (Miller and Herbicide treatments were applied with are a significant problem in most fields. Weed Hopen, 1991; Weaver, 1984). aCO-pressurized backpack sprayer cali- competition may reduce cabbage growth, 2 As with most minor crops, registered brated to deliver 280 L·ha–1 of spray volume quality, and yield by competing for nutrients, herbicides for use in cabbage are limited. with a single 8002EVS nozzle (Teejet Tech- sunlight, and soil moisture (Al-Khatib et al., Bensulide, clomazone, DCPA, oxyfluorfen, nologies, Wheaton, IL) and a pressure of 0.24 1995; Bhowmik and McGlew, 1986; Hoyt and trifluralin are registered for preplant MPa. PRE-T treatments included clomazone et al., 1996; Webster, 2010). The most incorporated application (Zotarelli et al., 2016). at 277 g a.i./ha, oxyfluorfen at 280 g a.i./ha, common weeds in Florida cabbage produc- Clethodim, clopyralid, DCPA, napropamide, pendimethalin at 798 g a.i./ha, DCPA + tion during the peak production period (De- and sethoxydim are registered for over-the- pendimethalin at 6715 + 798 g a.i./ha, cember through February) are winter annuals top applications (Zotarelli et al., 2016). and oxyfluorfen + pendimethalin at 280 + such as cutleaf evening primrose (Oenothera S-metolachlor controls annual broadleaf and 798 g a.i./ha (Table 1). PRE-T treatments laciniata Hill.) and wild radish (Raphanus grass weeds and suppress nutsedge species were applied to the bed top at 1 d before (Anonymous, 2014; Bellinder et al., 1989; transplanting. POST-T treatments included Sikkema et al., 2007). It is registered with DCPA at 6715 g a.i./ha, napropamide at a third-party identified label in Florida, and 2242 g a.i./ha, S-metolachlor at 1170 g a.i./ha, Received for publication 23 Oct. 2017. Accepted growers need to sign an agreement with the napropamide + S-metolachlor at 2242 + for publication 15 Dec. 2017. third-party indemnitors. The field half-life of Research funding was provided by Florida De- 1170 g a.i./ha, and DCPA + S-metolachlor at partment of Agriculture and Consumer Services. S-metolachlor is generally 15–25 d based on 6715 + 1170 g a.i./ha. POST-T treatments were We would like to thank Mike Sweat for technical direct bioassay measurements in southern states applied immediately after transplanting. In assistance with this research. (Shaner, 2014). Now, most cabbage growers in addition, the PRE-T fb sequential application 1Corresponding author. E-mail: nsboyd@ufl.edu. Florida use a single application of S-metolachlor at 3 WATP included oxyfluorfen at 280 g a.i./ha
646 HORTSCIENCE VOL. 53(5) MAY 2018 DISEASE AND PEST MANAGEMENT
Table 1. Product information of herbicides included in programs for Florida cabbage production. Herbicide Trade name Manufacturer Clopyralid StingerÒ 3 EC Dow AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN 46268 Clomazone CommandÒ3 ME FMC Corporation, Agricultural Products Group, Philadelphia, PA 19103 DCPA DacthalÒ 75 WP AMVAC, 4100 E. Washington Blvd. Los Angeles, CA 90023 Napropamide DevrinolÒ 50 DF United Phosphorus, Inc., 630 Freedom Business Center, Suite 402, King of Prussia, PA 19406 Oxyfluorfen GoalÒ 2XL Dow AgroSciences LLC, 9330 Zionsville Road, Indianapolis, IN 46268 Ò Pendimethalin Prowl H2O BASF Corporation, 26 Davis Drive, Research Triangle Park, NC 27709 S-metolachlor Dual Magnum IIÒ Syngenta Crop Protection, LLC, Greensboro, NC 27419 fb pendimethalin at 798 g a.i./ha. The POST-T 3 WATP initially provided <70% weed consistently provided >70% weed control fb sequential application at 3 WATP included control at 4 WATP. However, these treat- across sites. In addition, PRE-T application S-metolachlor at 1770 g a.i./ha fb pendimetha- mentsweremoreeffectiveattheendof of oxyfluorfen, POST-T application of nap- lin at 798 g a.i./ha or clopyralid at 210 g ae/ha. growing season and provided 90% and 89% ropamide and S-metolachlor, and PRE-T Weed-free treatments were hand-weeded once weed control at 13 WATP, respectively. application of DCPA + pendimethalin, as per week, whereas nontreated control remained S-metolachlor POST-T fb clopyralid 3 WATP well as sequential treatments of oxyfluorfen undisturbed throughout the growing season. provided >75% weed control throughout the fb pendimethalin and S-metolachlor fb Data collection. Weeds were counted in growing season. The PRE-T application of pendimethalin were less effective but consis- a61· 71-cm quadrat in each plot at 4, 5, and clomazone, oxyfluorfen, and pendimethalin, tently suppressed weeds across all sites. 13 WATP in Balm, and 2 and 8 WATP in as well as the POST-T application of DCPA A single PRE-T or POST-T application of Parrish. Grassy weeds and nutsedge were not and napropamide were less effective and weed clomazone, oxyfluorfen, pendimethalin, DCPA, counted in Balm because they did not occur at control never exceeded 70%. and napropamide did not provide a season-long this location. Weed control was visually In Citra, POST-T application of napropamide, weed control. A single POST-T application of evaluated in Citra at 2, 4, and 6 WATP on napropamide + S-metolachlor, and DCPA + S-metolachlor was effective in Balm, but this a percent scale where 0 equals no control and S-metolachlor, and PRE-T application of treatment was less effective and provided poor 100 equals complete desiccation. oxyfluorfen + pendimethalin, as well as weed control by the end of growing season in Cabbage injury where 0 represents no the sequential treatment of S-metolachlor Citra and Parrish. This response is not surprising injury and 100 represents complete desicca- POST-T fb clopyralid provided >70% weed because weeds germinate throughout the grow- tion was evaluated at 2, 4, and 8 WATP at all control at all ratings (Table 2). POST-T ing season, but herbicides break down over time sites. Five cabbage plants in each plot were application of S-metolachlor fb clopyralid 3 in the soil (Choi et al., 1988; Das et al., 2003; randomly selected for measuring height and WATP was the most effective treatment and Gillespie et al., 2011; Shaner, 2014). As a result, width. Cabbage height was measured at 6 provided $84 weed control at all ratings. sequential herbicide applications generally WATP at all sites. Cabbage width was PRE-T application of clomazone at 277 g·ha–1 resulted in better weed control compared measured at 10 WATP at Balm and Citra. and DCPA + pendimethalin at 6715 + with a PRE-T–only or POST-T–only appli- Cabbage heads were harvested on 8 Mar. and 798 g·ha–1 initially provided >70% weed cation program. 24 Mar. 2016 in Balm and 21 Mar. and 12 control at 2 WATP but control declined In previous research, Al-Khatib et al Apr. 2016 at Citra. Cabbage was not har- to <45% at 4 and 6 WATP. PRE-T applica- (1995) evaluated the control of broadleaf vested at the Parrish location because it was tion of pendimethalin and POST-T applica- weeds, including common lambsquarters accidentally harvested by a farm crew. tion of DCPA were less effective and weed (C. album L.), common chickweed [Stellaria Experimental design and data analysis. control never exceeded 70%. media (L.) vill], hedge mustard [Sisymbrium Treatments were arranged in a randomized In Parrish, broadleaves and nutsedges officinale (L.) Scop.], pineapple weed [Matricaria complete block design with four replications were counted separately at 2 WATP. PRE-T matricarioides (less.) Porter], shepherd’s at all sites. Weed count data were converted application of oxyfluorfen and DCPA + purse [Capsella bursa-pastoris (L.) Medic.], to percentage of control. Data were analyzed pendimethalin, and POST-T application of and redroot pigweed (Amaranthus retroflexus in SAS (version 9.2; SAS Institute, Inc., DCPA + S-metolachlor, as well as sequential L.), with clopyralid, trifluralin, oxyfluorfen, Cary, NC) using the PROC GLM. Data were treatment of S-metolachlor fb pendimethalin pendimethalin, pridate, and S-metolachlor in checked for normality and constant variance provided $95% control of broadleaf weeds. cabbage grown for seed and found that no before analysis. Logarithmic transformation POST-T application of S-metolachlor, nap- single herbicide controlled these broadleaf was used when needed to normalize the data. ropamide + S-metolachlor, and DCPA + weeds adequately, with the exception of Nontransformed data are presented. Treat- S-metolachlor provided >80% control of pendimethalin at 1.92 and 3.84 kg·ha–1,but ment means were compared using the least nutsedges. Sequential treatments included the combinations of trifluralin + oxyfluorfen, squares means statement in SAS with the S-metolachlor POST-T fb pendimethalin 3 pendimethalin + clopyralid, and oxyfluorfen + Tukey adjustment at P = 0.05. Data collected WATP and S-metolachlor POST-T fb clo- pyridate provided effective control. In the on multiple dates, such as weed control and pyralid 3 WATP provided 90% and 71% present study, improved weed control ob- cabbage yield, were analyzed using the re- control of nutsedges, respectively. POST-T served with combinations might be due to peated statement. application of napropamide + S-metolachlor the complementary weed control spectrum of and DCPA + S-metolachlor provided 78% each herbicide in the combinations. Results and Discussion and 76% weed control at 8 WATP (Table 2). Cabbage injury and productivity. Results Sequential herbicide treatments included of variance analysis showed that the site Weed control. The treatment by date S-metolachlor POST-T fb pendimethalin effect was significant (<0.0001) for cabbage interaction was significant at all sites and 3 WATP and S-metolachlor POST-T fb injury, height, width, total count, and cumu- as a result, the weed control data are pre- clopyralid 3 WATP provided 81% and 92% lative yield, and thus, data are presented sented separately by date (Table 2). In Balm, weed control at 8 WATP. The other herbicide separately by site. The treatment by time POST-T application of S-metolachlor, nap- treatments were less effective and weed interaction was not significant in any site ropamide + S-metolachlor, and DCPA + control never exceeded 70% at 8 WATP. and as a result, cumulative cabbage counts S-metolachlor provided $75% weed control In summary, the POST-T application of and yields are presented, whereas cabbage throughout the growing season (Table 2). napropamide + S-metolachlor and DCPA + injury, height, and width data are averaged Sequential treatments included oxyfluorfen S-metolachlor, and sequential treatment of across dates. PRE-Tfbpendimethalin3WATPand S-metolachlor fb clopyralid were the most In Balm, all herbicide treatments were S-metolachlor POST-T fb pendimethalin effective herbicide treatments because they safe on cabbage and injury never exceeded
HORTSCIENCE VOL. 53(5) MAY 2018 647 1% (Table 3). In Citra, clomazone injured cabbage 64%, whereas all other herbicide
Weed treatments injured cabbage <5%. In Parrish,
control (%) POST-T application of DCPA, and se- quential application of oxyfluorfen PRE fb pendimethalin 3 WATP, and S-metolachlor POST-T fb clopyralid 3 WAPT injured cab- bage the most, but injury never exceeded Parrish Nutsedge
control (%) 11%. All other herbicide treatments injured cabbage #9%. In addition, individual cab- bage head height and diameter were not significantly affected by herbicide treatments (data not shown). 2 WATP 2 WATP 8 WATP Broadleaf control (%) Al-Khatib et al (1995) reported that the PRE-T application of pendimethalin, triflu- ralin, and oxyfluorfen and POST-T applica- tion of clopyralid and metolachlor caused transitory cabbage injury. The authors also noted that sequential treatments included
. PRE-T fb POST-T treatments of oxyfluorfen ; different uppercase letters within columns indicated significant
P fb clopyralid and pendimethalin fb clopyralid injured cabbage <7% by 70 d after initial treatment. Bhowmik and McGlew (1986) noted that PRE-T application of oxyfluorfen –1 tests at 0.05 alone at 430 g·ha or fb sequential post- emergence grass herbicides provided effec- tive weed control without negative effects on cabbage yield and quality. Our re- sults indicated that treatments including S-metolachlor POST-T application is safe on cabbage without harmful effect on cabbage yield. A field research trial con-
Weed control (%) ducted in Ontario, Canada, showed that S-metolachlor applied PRE-T and POST-T at 800, 1600, and 2400 g·ha–1 had an acceptable level of crop safety in cabbage (Sikkema et al., 2007). There were no significant differences
Balm Citra among herbicide treatments and the weedy .
P and weed-free checks for the number of cabbage heads harvested and cumulative yield in Balm. In Balm, the cumulative cabbage head and yield averaged across treatments were 32,117 number/ha and 4 WATP 5 WATP 13 WATP 2 WATP 4 WATP 6 WATP 67,635 kg·ha–1, respectively (Table 3). In Citra, the lowest cumulative cabbage yield was obtained with the clomazone treatment. There was no cabbage harvested from the plots treated with PRE-T application of
(g a.i./ha) clomazone. The other herbicide treatments z were not significantly different from the weed-free checks. Overall, although several herbicide treatments injured cabbage, the injury was temporary and did not signifi- cantly reduce total head count and yield compared with weed-free plots, except the treatment of clomazone. It is important to note that the PRE-T application of clomazone might be safe for other cabbage varieties. Hopen et al (1993) examined 36 cabbage varieties with differ- ential genetic makeup and found that the cabbage varieties ‘Bravo’, ‘Cheers’, and ‘Genesis’ developed the most severe chloro- sis symptoms, whereas the other varieties such as ‘Bently’, ‘Carlton’, and ‘Cecile’ had the least chlorosis following clomazone at 600 and 1100 g a.i./ha. In the present study, inconsistent cabbage damage across sites by clomazone might be attributed to Clopyralid rate is listed as g ae/ha. PRE-T = pretransplanting; POST-T = posttransplanting; fb = followed by; WATP = weeks after transplanting. Herbicide Timing Rate Table 2. Weed control with herbicide programs in cabbage in three field experiments conducted from Nov. 2015 to Apr. 2016 in Balm, Citra, and Parrish, FL z difference for treatments that excluded nontreated and weed-free controls by Tukey tests at 0.05 NontreatedWeed freeClomazoneOxyfluorfenPendimethalinDCPANapropamideS-metolachlorDCPA + pendimethalinOxyfluorfen + pendimethalinOxyfluorfen fb pendimethalin PRE-TNapropamide + PRE-T S-metolachlor PRE-T PRE-TDCPA + PRE-T S-metolachlor PRE-T fb 3S-metolachlor WATP fb POST-T pendimethalin POST-TS-metolachlor fb clopyralid POST-T POST-T fbDifferent 3 POST-T lowercase letters WATP within columns 280 denoted significant fb difference 798 for treatments POST-T that included nontreated POST-T and 1,770 weed-free fb fb controls 3 by 798 Tukey WATP 33 a–d 280 (A–C) + 6,715 2,242 277 798 + + 65 798 1,770 1,770 a–d fb 280 (A–C) 798 210 71 ab (A) 2,242 39 84 a–d 29 99 ab 1,770 76 (A–C) a a–d (A) a–c (A) (A–C) (AB) 6,715 6,715 + 90 18 1,770 –5 ab b–d d (A) (A–C) 74 (C) ab (A) 4 95 32 cd 77 89 a a–d (B–C) ab 87 ab 75 (A) (A–C) (A) ab (A) a–c (A) (A–B) 95 0 84different a d 33 ab (A) (—) a–d (A) 85 34 50 100 29 75 (A–C) d cd ab a ab ab 83 (AB) (B) (A) (—) (A) (A) a–c 84 (AB) ab 86 99 86 (AB) cd a 53 ab (AB) (A) a–c 33 (A) (AB) ab 50 90 (A) 63 46 88 a–c b–d a–c b–d b–d (AB) (A) (AB) (AB) 100 (A) 91 0 a 70 88 a 75 b (—) ef b 80 (A) a–c (—) (CD) 94 b–d (A) (AB) 69 ab (A) a–cenvironments (A) 85 (AB) 92 63 d bc fg (AB) 75 (A) (CD) 100 e a (BC) 83 84 (—) 90 77 ab bc 85 50 ab cd (AB) (A) d (A) cd (A) 41 (AB) (A–D) 58 78 e g b–d (B) 0 (D) (A) (—) 87 b–d 72 100 (AB) 35 d 77 a e (A) cd 84 (—) 40 83 (B) (A) ab e ab 99 (AB) (B) 76 (AB) a 37 71 cd (A) 41 de ab (A) de (B–D) (A) (B–D) 17 0 73 e–g h bc (D) 70 71 23 30 (—) (A–C) d f bc d–f 77(Hopen 100 (A) (A–C) (B) 74 (CD) ab 90 a ab 80 (A) ab (—) (A) 14 ab (A) 95 ab 95 (AB) a (A) a (A) (A) 87 ab 75 (A) ab 42 (A) 29 50 100 de 71 ab ab 30 a (B–D) ab 8 (A) (A) ab (—) (A) fg 81 (A) (D) 61 a 0 32 11 ab g (A) 99 ab a (A) (—) a (A) (A) 81 (A)et ab 35 (A) ab (A) 17 41 91 ab ab a 92 (A) (A) (A) 100 43 a a aal., (A) (—) (A) 33 84 32 27 ab ab a 0 a (A) (A) (A) g (A) 78 (—) a 21 (A) 81 a ab 100 (A) 20 32 (A) a a a (—) (A) (A) 40 ab 76 (A) a (A) 100 a 66 (—) 0 a b (A) (—) 46 a (A) 0 b (—) 0 b (—)
648 HORTSCIENCE VOL. 53(5) MAY 2018 1993; Loux et al., 1989; Shaner, 2014). Hopen et al (1993) reported that cabbage damage by clomazone was more pro- nounced during a dry soil period. Soil type
) was also noted to significantly influence –1 the availability and soil persistence of ha · clomazone (Loux et al., 1989; O’barr et al., 2007; Shaner, 2014) and thereby the cabbage tolerance. In summary, all of the herbicide treat- ments evaluated except clomazone are safe for use in ‘Bravo’ cabbage in Florida. The tank-mix combinations of napropa- mide + S-metolachlor and DCPA + S-metolachlor, and sequential treatment of S-metolachlor fb clopyralid were the most effective herbicide treatments for weed control.
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tests at 0.05 Anonymous, 2014. Dual II magnum. Syngenta Crop Protection, LLC, Greensboro, NC. Bellinder, R., D. Wilcox-Lee, A. Senesac, and D. Warholic. 1989. Response of early- maturing cabbage (Brassica oleracea var. capitata) to metolachlor. Weed Technol. 3:463– 466. Bhowmik, P.C. and E.N. McGlew. 1986. Effects of oxyfluorfen as a pretransplant treatment on weed control and cabbage yield. J. Amer. Soc. Hort. Sci. 111:686–689. Choi, J., T. Fermanian, D.J. Wehner, and L. Spomer.
(%) (no./ha) (kg 1988. Effect of temperature, moisture, and soil texture on DCPA degradation. Agron. J. Visual injury Head count Yield
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Balm Citra Parrish Balm Citra Balmganisms Citra and their persistence in rice fields. 0 a (—)0 a (—) 0 c (—) 0 c (—) 0 a (—) 0 a (—) 29,575 a (—) 35,582 a (—) 19,749 a–c (—) 22,442 a–c (—) 58,190 a (—) 85,545 a (—) 18,299 b (—) 27,547 ab (—) Chemosphere 53:217–221. Gillespie, W.E., G.F. Czapar, and A.G. Hager. 2011. Pesticide fate in the environment: a guide for field inspectors. Contract Rpt. 7:5–12. Hopen, H.J., R.L. Hughes, and B.A. Michaelis. (g a.i./ha)
z 1993. Selectivity among cabbage (Brassica oleracea L.) cultivars by clomazone. Weed Technol. 7:471–477. Hoyt, G.D., A.R. Bonanno, and G.C. Parker. 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., R.A. Liebl, and F.W. Slife. 1989. Availability and persistence of imazaquin, imazethapyr, and clomazone in soil. Weed Sci. 37:259–267. Miller, A.B. and H.J. Hopen. 1991. Critical weed- control period in seeded cabbage (Brassica oleracea var capitata). Weed Technol. 5:852– 857. O’barr, J.H., G.N. McCauley, R.W. Bovey, S.A. Senseman, and J.M. Chandler. 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.,N.Soltani,W.Deen,andD.E. Clopyralid rate is listed as g ae/ha. PRE-T = pretransplanting; POST-T = posttransplanting; fb = followed by; WATP = weeks after transplanting. Table 3. Cabbage injury and yield following herbicide treatments in three field experiments conducted from Nov. 2015 to Apr. 2016 in Balm, Citra, and Pa z Herbicide Timing Rate difference for treatments that excluded nontreated and weed-free controls by Tukey tests at the 0.05 Nontreated Weed-free ClomazoneOxyfluorfenPendimethalinDCPANapropamideS-metolachlorDCPA + pendimethalinOxyfluorfen + pendimethalinOxyfluorfen fb pendimethalinNapropamide + S-metolachlor PRE-TDCPA + S-metolachlor PRE-T PRE-TS-metolachlor PRE-T fb pendimethalin PRE-TS-metolachlor PRE-T fb fb 3 clopyralid WATP POST-TDifferent POST-T lowercase letters within columns POST-T denoted POST-T significant difference fb for 3 treatments POST-T that WATP included nontreated and weed-free controls by Tukey POST-T POST-T 280 fb fb 3 798 WATP 1,770 fb 798 280 277 + 6,715 2,242 798 + + 280 798 1,770 1,770 1 798 fb a 210 (A) 0 a 2,242 (A) 1,770 0 6,715 6,715 a + 1 (A) 1,770 a 0 0 (A) a a 1 0 (A) (A) c a (B) (A) 0 0 a 0 aRobinson. (A) c (A) (B) 0 a 2 1 (A) bc a 0 (B) (A) a 0 (A) c 64 0 0 1 (B) 10 a c a c a (A) (B) (A) (B) (A) 1 0 c c (B) 2 (B)2007. a (A) 1 c 4 2 (B) b bc 8 (B) (B) a (A) 32,348 10 5 a 0 a 1 a (A) 8 c (A) a (A) a (B) (A) (A)Effect 34,658 0 a 0 a (A) a (A) (A) 5 a 3,096 9 7 (A) a a 27,726 a 31,423 18,402 (A) (A) a (A) 35,582 a 33,272 11 bc (A) a (A)of a a (A) (A) (A) (A) 20,197 36,505 a–c 31,423 a (A) a (A)S-metolachlor (A) 33,743 a 32,810 32,348 (A) a 19,749 a 68,863 (A) a–c (A) 26,802 26,930 a (A) 16,607 a ab (A) 18,402 c (A) (A) bc (A) (A) 71,336 23,788 a a–c (A) (A) 29,623 21,095 a a–c 0 (A) (A) d 58,469 (B) 26,597 a 23,329 58,915 ab (A) 64,840 15,709 16,605 a–c a (A) a c c (A) (A) (A) (A) (A) 7,058 23,347 a 77,833 ab (A) a (A) (A) 62,639 a 74,186 (A) a 72,887 (A) a (A) 19,663 57,589 68,486 64,169 b a a a 33,463 (A) (A) 18,889 (A) (A) a b (A) (A) 28,150 17,159 ab b (A) (A) 24,527 34,440 ab a (A) (A) 27,764 ab (A) 18,482 18,686 b b (A) (A) 0 c (B)
HORTSCIENCE VOL. 53(5) MAY 2018 649 application timing on cabbage tolerance. Crop Statistics Service. 20 May 2017.
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