Abstract
A 2-yr field study was conducted in Blackville, SC, to assess the potential for using small- grain cover crops and glyphosate as a means of reducing or eliminating the need for atrazine in irrigated Southeastern corn production. Oats, rye, and wheat were no-till, drill seeded each fall and subsequently desiccated in early spring before corn planting. A bareground conventional tilled treatment also was included. Within each cover crop system, the herbicides evaluated included (1) no herbicide; (2) 1.68 kg ai/ha atrazine plus 1.08 kg ai/ha S-metolachlor at corn planting followed by 0.84 kg ae/ha glyphosate; or (3) two applications of 0.84 kg/ha glyphosate alone, applied sequentially. All systems were compared with conventional tillage without a cover crop with 1.68 kg/ha atrazine plus 1.08 kg/ha S-metolachlor at planting followed by 1.12 kg/ha atrazine. Biomass of rye, oats, and wheat at dessication was 497, 369, and 340 g/m2, respectively. All cover crops delayed early-season corn growth. Detrimental effects on early-season corn growth from the oats cover crop were still apparent 7 wk after emergence (WAE), with corn height and biomass reduced 8 and 19%, respectively. Weed biomass in nontreated plots was reduced 84, 68, and 21% by oats, rye, and wheat, respectively, 3 WAE. Oats were more inhibitory of corn and weed growth than rye, although rye produced greater surface residue, indicating possible allelopathy affects. In the presence and absence of each cover crop, atrazine plus S-metolachlor followed by glyphosate or sequential glyphosate applications alone were effective in providing season-long control of pitted morningglory, entireleaf morningglory, Palmer amaranth, Florida pusley, large crabgrass, and common bermudagrass. Corn yields and gross profit margins in sequential glyphosate–treated plots were equivalent or superior to the standard atrazine-based program, which indicates that effective and economical alternatives to atrazine are available.Nomenclature: Atrazine; glyphosate; S-metolachlor; common bermudagrass, Cynodon dactylon (L.) Pers. #3 CYNDA; entireleaf morningglory, Ipomoea hederacea var. integriuscula Gray # IPOHG; Florida pusley, Richardia scabra L. # RCHSC; large crabgrass, Digitaria sanguinalis (L.) Scop. # DIGSA; Palmer amaranth, Amaranthus palmeri S. Wats. # AMAPA; pitted morningglory, Ipomoea lacunosa L. # IPOLA; corn, Zea mays L. ‘DK662 RR’; oats, Avena sativa L. ‘Coker 820’; rye, Secale cereale L. ‘Wrenz’; wheat, Triticum aestivum L. ‘Pioneer 2684’.Additional index words: Allelopathy, conservation tillage, integrated weed management, strip tillage, transgenic corn.Abbreviations: POST, postemergence; WAE, weeks after emergence.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 14
Claim · model-written summary
Rye biomass at desiccation was 497 g/m2.
- Taxon
- rye
Secale cerealee0 - Outcome
- Biomasse0
- Value
- 497e0
Not reportedOrgan / stage
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Biomass of rye, oats, and wheat at dessication was 497, 369, and 340 g/m2, respectively.”
Claim · model-written summary
Oats biomass at desiccation was 369 g/m2.
- Taxon
- oats
Avena sativae0 - Outcome
- Biomasse0
- Value
- 369e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Biomass of rye, oats, and wheat at dessication was 497, 369, and 340 g/m2, respectively.”
Claim · model-written summary
Wheat biomass at desiccation was 340 g/m2.
- Taxon
- wheat
Triticum aestivume0 - Outcome
- Biomasse0
- Value
- 340 g/m2e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Biomass of rye, oats, and wheat at dessication was 497, 369, and 340 g/m2, respectively.”
Claim · model-written summary
All cover crops delayed early corn growth.
- Taxon
- corn
Zea mays subsp. mayse0 - Treatment
- All cover cropse0
- Outcome
- early-season corn growthe0
- Direction
- delayede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“All cover crops delayed early-season corn growth.”
Claim · model-written summary
Oats reduced corn height by 8% at seven weeks after emergence.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- oats cover crope0
- Outcome
- corn heighte0
- Direction
- reducede0
- Value
- 8e0
- Qualifier
- 7 wk after emergencee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Detrimental effects on early-season corn growth from the oats cover crop were still apparent 7 wk after emergence (WAE), with corn height and biomass reduced 8 and 19%, respectively.”
Claim · model-written summary
Oats reduced corn biomass by 19% at seven weeks after emergence.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- oats cover crope0
- Outcome
- biomasse0
- Direction
- reducede0
- Value
- 19%e0
- Qualifier
- 7 wk after emergencee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Detrimental effects on early-season corn growth from the oats cover crop were still apparent 7 wk after emergence (WAE), with corn height and biomass reduced 8 and 19%, respectively.”
Claim · model-written summary
Oats reduced weed biomass by 84% at three weeks after emergence.
- Taxon
- cornZea mays subsp. mayst0
- Treatment
- oatse0
- Interactor
- Weede0weed
- Outcome
- Weed biomasse0
- Direction
- reducede0
- Value
- 84e0
- Comparator
- nontreated plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Weed biomass in nontreated plots was reduced 84, 68, and 21% by oats, rye, and wheat, respectively, 3 WAE.”
t0“Corn”
Claim · model-written summary
Rye reduced weed biomass by 68% at three weeks after emergence.
- Taxon
- cornZea mays subsp. mayst0
- Treatment
- ryee0
- Interactor
- Weede0weed
- Outcome
- Weed biomasse0
- Direction
- reducede0
- Value
- 68e0
- Comparator
- nontreated plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Weed biomass in nontreated plots was reduced 84, 68, and 21% by oats, rye, and wheat, respectively, 3 WAE.”
t0“Corn”
Claim · model-written summary
Wheat reduced weed biomass by 21% at three weeks after emergence.
- Taxon
- cornZea mays subsp. mayst0
- Treatment
- wheate0
- Interactor
- Weede0weed
- Outcome
- Weed biomasse0
- Direction
- reducede0
- Value
- 21%e0
- Comparator
- nontreated plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Weed biomass in nontreated plots was reduced 84, 68, and 21% by oats, rye, and wheat, respectively, 3 WAE.”
t0“Corn”
Claim · model-written summary
Oats inhibited corn and weed growth more than rye.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- Oatse0
- Interactor
- weede0weed
- Outcome
- corn and weed growthe0
- Direction
- more inhibitorye0
- Comparator
- ryee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Oats were more inhibitory of corn and weed growth than rye, although rye produced greater surface residue, indicating possible allelopathy affects.”
Claim · model-written summary
Rye produced more surface residue than oats.
- Taxon
- ryeSecale cerealee0
- Outcome
- surface residuee0
- Direction
- greatere0
- Comparator
- Oatse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Oats were more inhibitory of corn and weed growth than rye, although rye produced greater surface residue, indicating possible allelopathy affects.”
Claim · model-written summary
Both herbicide programs controlled the listed weeds throughout the season across cover crop conditions.
- Taxon
- cornZea mays subsp. mayst0
- Treatment
- atrazine plus S-metolachlor followed by glyphosate or sequential glyphosate applications alonee0
- Interactor
- pitted morningglorye0weed
- Outcome
- season-long control of pitted morningglory, entireleaf morningglory, Palmer amaranth, Florida pusley, large crabgrass, and common bermudagrasse0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the presence and absence of each cover crop, atrazine plus S-metolachlor followed by glyphosate or sequential glyphosate applications alone were effective in providing season-long control of pitted morningglory, entireleaf morningglory, Palmer amaranth, Florida pusley, large crabgrass, and common bermudagrass.”
t0“Corn”
Claim · model-written summary
Sequential glyphosate plots had equivalent or superior corn yields compared with the atrazine program.
- Taxon
- CornZea mays subsp. mayse0
- Treatment
- sequential glyphosate–treatede0
- Outcome
- Corn yieldse0
- Direction
- equivalent or superiore0
- Comparator
- standard atrazine-based programe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Corn yields and gross profit margins in sequential glyphosate–treated plots were equivalent or superior to the standard atrazine-based program”
Claim · model-written summary
Sequential glyphosate plots had equivalent or superior gross profit margins compared with the atrazine program.
- Taxon
- CornZea mays subsp. mayse0
- Treatment
- sequential glyphosate–treatede0
- Outcome
- gross profit marginse0
- Direction
- equivalent or superiore0
- Comparator
- standard atrazine-based programe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Corn yields and gross profit margins in sequential glyphosate–treated plots were equivalent or superior to the standard atrazine-based program”
The same questions in other papers
Avena sativa · growth · Zea mays (maize)Positive and negative results
1 paper in the same direction as this paper · 1 in the opposite direction
- positive
- negative
Triticum aestivum · weed · Zea mays (maize)Positive and negative results
12 papers in the same direction as this paper · 1 in the opposite direction
- no effect
- positive
- positive
10 papers more in this group
See all 14 papers →glyphosate · control · Zea mays (maize)Positive and negative results
35 papers in the same direction as this paper · 5 in the opposite direction
- no effect
- negative
- negative
37 papers more in this group
See all 41 papers →atrazine · control · Zea mays (maize)Positive and negative results
68 papers in the same direction as this paper · 15 in the opposite direction · 2 reporting no difference from an alternative
- negative
- negative
- no effect
82 papers more in this group
See all 86 papers →Avena sativa · weed · Zea mays (maize)Results agree
1 paper in the same direction as this paper
- positive
cover crop · growth · Zea mays (maize)Results differ
11 papers in the same direction as this paper · 16 in the opposite direction
- positive
- positive
- positive
24 papers more in this group
See all 28 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.