The Experts below are selected from a list of 186 Experts worldwide ranked by ideXlab platform
Kai Umeda - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of New Preemergence Herbicides Alone and in Combinations for Weed Control in Melons
2015Co-Authors: Kai UmedaAbstract:Azafenidin (Milestone®, Dupont) and flumioxazin (Valor®, Valent)) caused cantaloupe injury that was very marginal between acceptable (<15%) and unacceptable (>15%). Flufenacet (Bayer), isoxaben (Gallery, DowAgroSciences), and thifensulfuron (Harmony®, Dupont) at the rates tested caused severe crop injury. Isoxaben provided very good weed control (>90%), azafenidin provided acceptable control of only lambsquarters at 88 % and less than acceptable (85%) control of pigweeds, purslane, and grasses, and flumioxazin at the higher rate of 0.05 lb AI/A tended to offer slightly better weed control than the lower rate but overall it was marginally acceptable. Bensulide (Prefar®) combined with flumioxazin caused negligible crop phytotoxicity and better than 93 % control for purslane, pigweeds, lambsquarters, and grasses. Combinations of herbicides offered slightly improved weed control compared to herbicides applied alone. Crop injury increased for combinations with dimethenamid (Outlook®, Frontier®, BASF) and s-metolachlor (Dual Magnum®, Syngenta)
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Weed Control in Glyphosate-Tolerant Lettuce (Lactuca sativa)1
Weed Technology, 2003Co-Authors: Steven A. Fennimore, Kai UmedaAbstract:Field studies were conducted in Arizona and California to evaluate the performance of glyphosate-tolerant lettuce and to determine the critical time of weed removal. Glyphosate was applied as a single or as a sequential application at 840 g ae/ha. Single glyphosate applications were made to lettuce at the two-, four-, six-, and eight-leaf stages. Sequential applications were made to lettuce at the two- or four-leaf stage followed by (fb) a second application 14 d after the first. Weed control efficacy, weeding times, and lettuce yield were all measured. Overall, glyphosate applied postemergence (POST) provided better weed control than the commercial standards Bensulide or pronamide applied preemergence. Single glyphosate applications at the four-leaf stage and sequential applications at the two-leaf stage fb a second application 14 d later provided excellent control of most weeds, including redroot pigweed. Estimates of the critical time of weed removal were 26 to 29 d after emergence. Glyphosate treatmen...
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Evaluation of New Preemergence Herbicides Alone and in Combinations for Weed Control in Melons
Vegetable Report, 2002Co-Authors: Kai UmedaAbstract:Azafenidin (Milestone®, Dupont) and flumioxazin (Valor®, Valent)) caused cantaloupe injury that was very marginal between acceptable ( 15%). Flufenacet (Bayer), isoxaben (Gallery, DowAgroSciences), and thifensulfuron (Harmony®, Dupont) at the rates tested caused severe crop injury. Isoxaben provided very good weed control (>90%), azafenidin provided acceptable control of only lambsquarters at 88% and less than acceptable (85%) control of pigweeds, purslane, and grasses, and flumioxazin at the higher rate of 0.05 lb AI/A tended to offer slightly better weed control than the lower rate but overall it was marginally acceptable. Bensulide (Prefar®) combined with flumioxazin caused negligible crop phytotoxicity and better than 93% control for purslane, pigweeds, lambsquarters, and grasses. Combinations of herbicides offered slightly improved weed control compared to herbicides applied alone. Crop injury increased for combinations with dimethenamid (Outlook®, Frontier®, BASF) and s-metolachlor (Dual Magnum®, Syngenta).
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Effect of Prowl and Prefar Herbicides on Onions
Vegetable Report, 2001Co-Authors: Kai Umeda, N. LundAbstract:Significant onion height reduction was observed when Prowl (pendimethalin) and Prefar (Bensulide) herbicide combinations were applied preemergence (PREE). The onions resumed growth but the height was still slightly reduced later in the growing season compared to the handweeded check and the standard herbicide treatment, Dacthal (DCPA). The onion crop stand emerged initially but later in the season, a significant crop stand reduction was observed for the higher rate of Prowl at 0.5 lb AI/A plus Prefar. A lower rate of Prowl at 0.25 lb AI/A plus Prefar also caused a reduction of the onion stand compared to the handweeded check or Dacthal.
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Evaluation of Herbicides for Cantaloupe Weed Control
1999Co-Authors: Kai UmedaAbstract:At 4 weeks after treatment (WAT), all preemergence (PREE) treatments were completely safe on cantaloupes. At 1 WAT of postemergence (POST) applications, marginally acceptable melon injury (11 to 19%) was observed. At 6 WAT, crop injury increased significantly for both halosulfuron and bentazon. Halosulfuron (POST) following Bensulide (PREE) caused minimal crop injury. The pigweeds were marginally controlled when POST treatments followed PREE herbicides. Tumble pigweed (Amaranthus albus) was more difficult to control than prostrate pigweed (A. blitoides). Halosulfuron gave good control of nutsedge (Cyperus rotundus) at 6 WAT.
D. Nandwani - One of the best experts on this subject based on the ideXlab platform.
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EFFECT OF PREEMERGENCE HERBICIDES ON QUALITY AND YIELD OF TRANSPLANTED WATERMELON (CITRULLUS LANATUS)
2013Co-Authors: V. Napolean-fanis, D. NandwaniAbstract:Field studies were conducted twice at two sites in St. Croix, United States Virgin Islands, to determine the effectiveness of preemergence applications of Bensulide and halosulfuron in transplanted watermelon. Bensulide and halosulfuron were both applied separately. Although Bensulide caused up to 5% seedling stunting and halosulfuron caused up to 10% seedling stunting and discoloration, watermelon plants were fully recovered by week 8 after planting. Yields of all treatments were similar to that of untreated plots. Control of grasses like goosegrass and of broadleaf weeds like amaranthus was not found in treated plots. Weed species, weed densities and the percentage of weed control found in Bensulide and halosulfuron treated plots were similar to non-treated plots. Watermelon fruits in both treated and non-treated plots had a degree of brix of 8.5, which indicates poor quality fruits.
B. Jack Johnson - One of the best experts on this subject based on the ideXlab platform.
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Influence of Spring-Applied Herbicides on Bermudagrass (Cynodon dactylon) Greens Overseeded with Roughstalk Bluegrass (Poa trivialis)
Weed Technology, 1998Co-Authors: B. Jack JohnsonAbstract:Premergence (PRE) herbicides were applied to a bermudagrass golf green overseeded with 'Laser' roughstalk bluegrass during 1995 and 1996 to determine their effects on roughstalk bluegrass injury and on the transition from a mixed cool- and warm-season grass back to the permanent bermudagrass. Roughstalk bluegrass tolerated single March applications of trifluralin plus benefin at 2.2 kg/ha, pendimethalin at 3.4 kg/ha, dithiopyr at 0.6 kg/ha, prodiamine at 0.8 kg/ha, Bensulide plus oxadiazon at 8.4 kg/ha, and Bensulide at 11.2 kg/ha. A single March application of oxadiazon plus benefin at 3.4 kg/ha severely injured (35%) the overseeded turf in 1 yr, but not when 1.7 kg/ha was applied in March and repeated in May. One-half recommended rates of oxadiazon and Bensulide plus oxadiazon applied in March did not cause any undesirable injury, but when repeated in May, mod- erate to severe injury (28 to 33%) occurred in June. Oryzalin at ' 1.1 kg/ha, benefin plus oryzalin at ? 1.1 kg/ha, and oxyfluorfen plus oryzalin at ' 1.7 kg/ha severely injured (' 35%) roughstalk bluegrass. The rate of transition of mixed roughstalk bluegrass and bermudagrass back to permanent bermudagrass was not affected by any of the PRE herbicides except when oryzalin was applied alone or in combination with benefin or oxyfluorfen. Nomenclature: Benefin, N-butyl-N-ethyl-2,6-dinitro-4-(trifluoromethyl)benzenamine; Bensulide, 0,0- bis(I-methylethyl) S-(2-((phenylsulfonyl)amino)ethyl)phosphorodithioate; dithiopyr, S,S-dimethyl 2-(di- fluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-3,5-pyridinedicarbothioate; oryzalin, 4-(dipropy- lamino)-3,5-dinitrobenzenesulfonamide; oxadiazon, 3-(2,4-dichloro-5-(1-methylethoxy)phenyl)-5-(1,1-di- methylethyl)-1,3,4-oxadiazol-2-(3H)-one; oxyfluorfen, 2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoro- methyl)benzene; pendimethalin, N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine; prodiamine, 2,4-dinitro-A'3,N3-dipropyl-6-(trifluoromethyl)-1,3-benzenediamine; trifluralin, 2,6-dinitro-N, N-dipropyl- 4-(trifluoromethyl)benzenamine; roughstalk bluegrass, Poa trivialis L. #3 POATR 'Laser'; bermudagrass, Cynodon transvaalensis Burtt-Davey # CYNTR X C. dactylon (L.) Pers. # CYNDA 'Tifway.' Additional index words: POATR, CYNTR, CYNDA. Abbreviations: AS, aqueous suspension; EC, emulsifiable concentrate; Fb, followed by; FC, flowable concentrate; G, granule; PRE, preemergence; WDG, water dispersible granule.
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Response of zoysiagrass cultivars to preemergence herbicides
1997Co-Authors: B. Jack JohnsonAbstract:ABSTRACT A field experiment was conducted over a 2-year period to evaluate the tolerance of five creeping bentgrass (Agrostis stolonifera L.) cultivars to preemergence herbicides. There was no herbicide-by-cultivar interaction. All herbicides applied at recommended rates maintained an acceptable quality (> 92% of untreated) throughout the spring and summer. Dithiopyr [.S,5-dimethyl-2-(di-fluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-3,5-pyridinedi-carbothioate] at 0.43 kg ha−1 reduced quality 5% within two weeks after treatment, while oxadiazon {3-[2,4-dichloro-5-(l-methylethoxy) phenyl]-5-(l, l-dimethylethyl)-l,3,4-oxadia201-2-(3//)-one} at 3.4 kg ha−1 and Bensulide [0,0-bis(l-methylethyl) 5-{2-[(phenylsulfomyl)-amino]ethy]phosphorodithioate} plus oxadiazon at 6.7 + 1.7 kg ha −1 reduced quality 8%. There was no difference in quality and density of creeping bentgrass when treated with Bensulide plus oxadiazon at IX (6.7 + 1.7 kg ha−1) and 3X (20.2 + 5.0 kg ha-1) rates. The quality was similar when ...
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Response of Fall-Seeded Tall Fescue (Festuca arundinacea) to Spring-Applied Herbicides
Weed Technology, 1991Co-Authors: B. Jack Johnson, Tim R. MurphyAbstract:Preemergence herbicides were applied on February 28 at the recommended and three times the normal rate to determine the tolerance of tall fescue that was seeded in September, October and November of the preceding year. Fall seeding date of tall fescue significantly affected its tolerance to spring-applied preemergence herbicides. Generally, preemergence herbicides at normal rates were safe to apply to September- or October-seeded tall fescue. No herbicide was completely safe to apply to November-seeded tall fescue. The density of November-seeded tall fescue was generally reduced less with benefin, Bensulide, dithiopyr, oxadiazon G and WP than with benefin plus oryzalin, oryzalin, or pendimethalin.
Kean S. Goh - One of the best experts on this subject based on the ideXlab platform.
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Detections of Eleven Organophosphorus Insecticides and One Herbicide Threatening Pacific Salmonids, Oncorhynchus spp., in California, 1991–2010
Bulletin of Environmental Contamination and Toxicology, 2011Co-Authors: Emily B. Lisker, Michael P. Ensminger, Sheryl L. Gill, Kean S. GohAbstract:California’s surface water monitoring results from 1991 through 2010 were analyzed to determine whether 12 organophosphorus insecticides and herbicides (i.e., azinphos methyl, Bensulide, dimethoate, disulfoton, ethoprop, fenamiphos, methamidophos, methidathion, methyl parathion, naled, phorate, and phosmet) and their degradates have been detected above maximum concentration limits (MCLs) in Pacific salmonid habitats. Methidathion, methyl parathion, phorate, phosmet, and the oxygen analogue of naled (DDVP) detections exceeded MCLs. Methyl parathion detections may be accounted for by monthly use trends, while methidathion detections may be explained by yearly use trends. There were inadequate phorate, phosmet, or DDVP data to evaluate for correlations with use.
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Detections of eleven organophosphorus insecticides and one herbicide threatening Pacific salmonids, Oncorhynchus spp., in California, 1991-2010.
Bulletin of environmental contamination and toxicology, 2011Co-Authors: Emily B. Lisker, Michael P. Ensminger, Sheryl Gill, Kean S. GohAbstract:California’s surface water monitoring results from 1991 through 2010 were analyzed to determine whether 12 organophosphorus insecticides and herbicides (i.e., azinphos methyl, Bensulide, dimethoate, disulfoton, ethoprop, fenamiphos, methamidophos, methidathion, methyl parathion, naled, phorate, and phosmet) and their degradates have been detected above maximum concentration limits (MCLs) in Pacific salmonid habitats. Methidathion, methyl parathion, phorate, phosmet, and the oxygen analogue of naled (DDVP) detections exceeded MCLs. Methyl parathion detections may be accounted for by monthly use trends, while methidathion detections may be explained by yearly use trends. There were inadequate phorate, phosmet, or DDVP data to evaluate for correlations with use.
Robert J. Mills - One of the best experts on this subject based on the ideXlab platform.
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Response of transplanted watermelon (Citrullus lanatus) to ethalfluralin applied PPI, PRE, and POST
Weed Technology, 1997Co-Authors: Wayne E. Mitchem, David W. Monks, Robert J. MillsAbstract:Field experiments conducted in 1992 and 1993 evaluated transplanted watermelon tolerance to ethalfluralin applied PPI, PRE (before transplanting), and POST (immediately after transplanting) at 1.2 or 2.4 kg ai/ha. Other treatments for comparison included the registered herbicides ethalfluralin POST-directed spray (PDS), ethalfluralin PDS followed by (fb) naptalam POST, Bensulide plus naptalam PPI, and a nontreated check. All treatments controlled common lambsquarters and goosegrass 83 to 100% 2 and 6 weeks after treatment (WAT). Watermelon was injured 30 to 77% in 1992 and 14 to 83% in 1993 by ethalfluralin PPI or PRE at 1.2 or 2.4 kg/ha. Ethalfluralin POST was not injurious to watermelon. In 1992, watermelon treated with ethalfluralin POST at 1.2 and 2.4 kg/ha yielded 52 to 62% more fruit than watermelon from the nontreated check. In 1993, yield of transplanted watermelon treated with ethalfluralin POST was similar to that in the nontreated check.