The postemergence-active herbicides lactofen, fomesafen, and acifluorfen were applied to established matted-row strawberry plants (Fragaria × ananassa) and evaluated for broadleaf weed control and foliar phytotoxicity. Strawberries were evaluated for yield and fruit quality. Treatments were applied following June renovation. All herbicide treatments resulted in acceptable control of broadleaf weeds present at the time of application; however, sicklepod (Cassia obtusifolia) germinated after herbicide application. All treatments caused foliar injury within 3 days after application. No injury symptoms were evident 21 days after treatment due to new foliage development. Fomesafen and acifluorfen were the only herbicides to suppress runner count. Yields the following year were not reduced by herbicide treatments. Chemical names used: (±)-2-ethoxy-l-methy1-2-oxoethyl 5-[2-chloro-4-(trifluoromethyl) phenoxy]-2-nitrobenzate (lactofen); 5-[2-chloro-4-(trifluoromethyl)phenoxy] -N -(methylsu1fonyl)-2-nitrobenzamide (fomesafen); 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid (acifluorfen).
A.W. Caylor, W.A. Dozier Jr., G. Wehtje, D.G. Himelrick, J.A. McGuire, and J.A. Pitts
John B. Masiunas
Experiments determined the effectiveness of the bipyridinium herbicides paraquat and diquat and of the diphenyl ether herbicide lactofen to desiccate onion (Allium cepa L.) shoots without affecting bulb quality and storage life. Paraquat, applied once, desiccated 80% of onion shoots within 3 days. Diquat desiccated ≈ 60% of onion shoots within 10 days of treatment. Lactofen caused slight necrosis but did not adequately desiccate onion shoots. Diquat and paraquat reduced sprouting of `Red Wethersfield' more than of `White Portugal'. Chemical names used: 6,7-dihydrodipyrido[l,2 2',1'-c] pyrazinediium ion (diquat); (±)2-ethoxy-l-methyl-2-oxoethy1 5-[2chloro-4-(trifluoromethyl)phenoxyl] -2-nitrobenzoate (lactofen); 1,1'-dimethyl-4,4'-bipyridinium ion (paraquat).
Bielinski M. Santos and Jose P. Morales-Payan
Trials were conducted under controlled conditions to determine the tolerance of young papaya plants (15 cm tall) to postemergence herbicides. Herbicides used were paraquat (1.68 Kg ai/Ha), MSMA (2.24 Kg ai/Ha), 2,4-D (4.26 Kg ai/Ha), bromoxynil (0.28 Kg ai/Ha), cyanazine (1.12 Kg ai/Ha), dimethenamid (1.12 Kg ai/Ha), endothal (0.56 Kg ai/Ha), imazameth (0.067 Kg ai/Ha), imazethapyr (0.028 Kg ai/Ha) lactofen (0.12 Kg ai/Ha), oxyfluorfen (0.03 Kg ai/Ha), acifluorfen (0.28 Kg ai/Ha), atrazine (2.24 Kg ai/Ha), and bentazon (1.12 Kg ai/Ha) as well as the untreated control. Atrazine, bentazon, cyanazine, imazemeth, imazethapyr, and dimethenamid did not cause phytotoxicity at the rates used and were equal to the untreated control. Other herbicides caused severe injuries followed by total death at 10 days after treatment.
Lu Zhang, Robert Howard Beede, Gary Banuelos, Christopher M. Wallis, and Louise Ferguson
et al. (2003) reported that in almonds ( Prunus dulcis Mill.), stigmatic papillae wrinkled, distorted, and collapsed following fungicide contamination. Similarly, in soybean ( Glycine max ), the herbicide lactofen activated singlet oxygen generation