Table 3 Phytotoxicity caused by various post-emergent herbicides in different varieties of hemp across the world

2,4-D, Ametryn, Amitrole, Atrazine, Bentazon, Diquat, Diuron, Ethofumesate, Fluometuron, Glyphosate, Karbutilate, Linuron, Methabenzthiazuron, Methazole, Metribuzin, Oxadiazon, Paraquat, Phenmedipham, Phenobenzuron, Prometryn, Terbutryn

Barban, Butralin, Dalapon, Difenzoquat, Dinitramine, Diphenamid, IPC, Penoxalin, Napropamide, Trifluralin, U-27267

Alachlor, Benefin, Benzthiazuron, Butylate, Chloroxuron, Cycloate, EPTC, Molinate, Nitralin, Nitrofen, Pebulate, Perfluidone, Pronamide, TFP, Vernolate

1–3 leaf pairs stage

-

USDA Plant introduction numbers 377927, 377,929, 377,935

Glasshouse/Israel

(Horowitz 1977)

Amitrole (2 kg/ha), Bentazon (2 ai kg/ha), Diquat + Praquat (0.4 ai kg/ha), Glyphosate (0.82 kg/ha), Ioxynil (1 kg/ha), Metribuzin (0.14 kg/ha), MSMA + cacodylate (1.9 ai kg/ha), Phenmedipham (0.66 ai kg/ha)

Bromoxynil (1 kg/ha)

10–20 cm tall

2 weeks after treatment

USDA-377927, 377,929, 377,935

Field/Israel

(Horowitz 1977)

Glyphosate (0.82 kg/ha)

Amitrole (2 kg/ha)

Ioxynil (1 kg/ha), Metribuzin (0.14 kg/ha)

Bromoxynil (1 kg/ha)

80 cm tall

2 weeks after treatment

USDA- 377,927, 377,929, 377,935

Field/Israel

(Horowitz 1977)

Triasulfuron (0.03 kg ai/ha), Tribenuron methyl (0.01125 kg ai/ha)

Chlopyralid (0.09 kg ai/ha)

Fluosiphor-p-butyl (0.15 kg ai/ha)

2–3 leaf pairs stage

-

zenit

Field/Neamt,Romania

(Chiriţă 2008)

Bispyribac-Na (0.02 kg/ha), Flazasulfuron (0.11 kg/ha), Rimsulfuron (0.07 kg/ha), Trifloxysulfuron (0.007 kg/ha)

Bromoxynil (0.58 L/ha), MSMA 3.16 L/ha)

4–5 leaf pairs stage/30.5 cm tall

2 weeks after treatment

Italian cultivars

Field/Kentucky, USA

(Maxwell 2016)

Trifloxysulfuron (0.007 kg/ha)

Flazasulfuron (0.11 kg/ha), Rimsulfuron (0.07 kg/ha)

Bispyribac-Na (0.02 kg/ha), Bromoxynil (0.58 L/ha), MSMA (3.16 L/ha)

4–5 leaf pairs stage/30.5 cm tall

2 weeks after treatment

Finola

Field/Kentucky, USA

(Maxwell 2016)

Bentazon (5.6 kg ai/ha), Fomesafen (0.2 kg ai/ha), Halosulfuron (0.05 kg ai/ha), Imazaquin (0.8 kg ai/ha), Imazethapyr (0.2 kg ai/ha), Linuron (1.4 kg ai/ha), Thifensulfuron (0.02 kg ai/ha)

Acifluorfen (2.2 kg ai/ha), Bromoxynil (0.3 kg ai/ha), Chlorimuron (0.02 kg ai/ha), Clopyralid (0.1 kg ai/ha), Pyrithiobac (3.6 kg ai/ha), Quizalofop (1.0 kg ai/ha), Sethoxydim (0.3 kg ai/ha)

20–28 cm tall

4 weeks after treatment

Felina 32

Greenhouse/Virginia, USA

(Byrd 2019)

Halosulfuron (0.05 kg ai/ha)

Bromoxynil (0.3 kg ai/ha), Clopyralid (0.1 kg ai/ha), Quizalofop (1 kg ai/ha), Sethoxydim (0.3 kg ai/ha)

20–28 cm tall

30 days after treatment

Helena 2017

Field/Virginia, USA

(Byrd 2019)

Halosulfuron (0.05 kg ai/ha)

Bromoxynil (0.3 kg ai/ha), Clopyralid (0.1 kg ai/ha), Quizalofop (1 kg ai/ha), Sethoxydim (0.3 kg ai/ha),

20–28 cm tall

30 days after treatment

Joey 2018

Field/Virginia, USA

(Byrd 2019)

Flucarbazone-sodium (0.0157 g ai/ha), Fluroxypyr-methyl (0.14 kg ae/ha), Halauxifen-methyl (0.0053 kg ai/ha), Glyphosate-potassium (0.84 kg ae/ha), Glufosinate-ammonium (0.655 kg ai/ha), Paraquat (0.28 kg ai/ha), Tembotrione (0.092 kg ai/ha), Topramezone (0.0123 kg ae/ha)

Nicosulfuron (0.0256 kg ai/ha), Pyroxsulam (0.0151 kg ai/ha), Tribenuron-methyl (0.0088 kg ai/ha), 2,4-D Amine 4 (0.28 kg ai/ha), Metribuzin (0.21 kg ai/ha), Carfentrazone-ethyl (0.009 kg ai/ha), Fomesafen-sodium (0.198 kg ai/ha)

Cloransulam-methyl (0.0175 kg ai/ha), Halosulfuron-methyl (0.0352 kg ai/ha), Imazamox-ammonium (0.035 kg ai/ha), Imazethapyr-ammonium (0.035 kg ai/ha), Triflusulfuron-methyl (0.0315 kg ai/ha), Dicamba (0.07 kg ae/ha), Atrazine (0.28 kg ai/ha), Bentazon-sodium (0.28 kg ai/ha), Oxyfluorfen (1.1204 kg ai/ha)

Bromoxynil (0.28 kg ai/ha), Clopyralid (0.105 kg ae/ha)

3 leaf pairs stage/8–12 cm tall

19 days after treatment

CFX-2

Greenhouse/North Dakota, USA

(Mettler 2021)

Cloransulam-methyl (0.018 g ai/ha), Oxyfluorfen (1.12 kg ai/ha)

Atrazine (0.28 kg ai/ha), Bromoxynil (0.28 kg ae/ha), Imazamox-ammonium (0.035 kg ae/ha), Quinclorac-methyl (0.29 kg ai/ha)

Clopyralid (0.105 kg ae/ha)

3 leaf pairs stage/8–12 cm tall

21 days after treatment

X-59

Field/North Dakota, USA

(Mettler 2021)

Dicamba (0.560 kg ae/ha)

2,4-D (1.060 kg ae/ha)

28 days after treatment

Tangerine

Greenhouse/Ohio, USA

(Essman 2022; Essman et al. 2024)

Isoxaflutole (0.112 kg ai/ha)

Isoxaben (0.631 kg ai/ha), Halosulfuron (0.039 kg ai/ha)

Dithiopyr (0.28 kg ai/ha), Metribuzin (0.21 kg ai/ha), Prometryn (1.121 kg ai/ha), S-metolachlor (1.068 kg ai/ha)

Acetochlor (0.841 kg ai/ha), Flumioxazin (0.072 kg ai/ha), Fomesafen (0.21 kg ai/ha), Norflurazon (0.138 kg ai/ha), Oxyfluorfen (0.421 kg ai/ha), Pendimethalin (1.065 kg ai/ha)

1–2 leaf pairs stage

2 weeks after treatment

Von

Treated 1 day before pretransplant in field/Georgia, USA

(Wright 2022; Wright-Smith et al. 2024)

Halosulfuron (0.026 kg ai/ha), Metribuzin (0.21 kg ai/ha), Prometryn (1.121 kg ai/ha), Trifloxysulfuron (0.005 kg ai/ha)

Imazethapyr (0.035 kg ai/ha)

Acetochlor (0.841 kg ai/ha), Clethodim (0.136 kg ai/ha), Pendimethalin (1.065 kg ai/ha), S-metolachlor (1.068 kg ai/ha)

13–18 cm tall

2 weeks after treatment

Sunbelt Crush

Treated posttransplant in field/Georgia, USA

(Wright 2022; Wright-Smith et al. 2024)

Bentazon (2.5 kg, L/ha)

Bromoxynil + 2,4-D(0.8 kg, L/ha), Clopyralid (0.5 kg, L/ha), Clethodim (1.5 kg, L/ha), Fluazifop-p-butyl (1.2 kg, L/ha)

25–30 cm tall/8–10 leaf pairs stage

4 weeks after treatment

Secuieni—Jubileu

Field/Botosani, Romania

(Puiu et al. 2023)

Bentazone (0.72 kg ai/ha)

Bromoxynil (0.3375 kg ai/ha)

Halosulfuron-methyl (0.030 kg ai/ha), Quizalop-p-ethyl (0.050 kg ai/ha)

30 days after planting

Finola

Field and Pot/Yozgat, Turkey

(Kale et al. 2024)

Clethodim (0.272 kg ai/ha), Fenoxaprop (0.086 kg ai/ha), Fluazifop (0.210 kg ai/ha), Fluazifop + Fenoxaprop (0.21 + 0.059 kg ai/ha), Pinoxaden (0.06 kg ai/ha), Quizalofop (0.092 kg ai/ha), Sethoxydim (0.315 kg ai/ha)

20–25 cm tall/2–3 leaf pairs stage

21 days after treatment

NWG2730 and NWG452

Greenhouse/Nebraska, USA

(Zaric 2023)