Abstract
Sunflower [ Helianthus annuus var. marcocapus (DC.) Ckll.) acreage has been increasing rapidly in the high elevation region of the central Great Plains. Little work has been done in the region on the effect of planting date and plant population on sunflower production. This study measured the influence of three planting dates (25 May, 10–13 June, and 28 June) and four populations (11 000, 14 000, 17 000, and 20 000 plants/ acre) on seed yield, oil percentage and yield Components of two full season sunflower oil type hybrids (‘Pioneer brand 707’ and ‘Sigco brand 475’). The latter is 7 to 8 d later in maturity and 4 in. taller than the Pioneer hybrid. The experiment was performed in three environments (supplemental water following corn [ Zea mays L.], dryland following wheat [ Triticum aestivum L. emend. Thell.], and dryland after 22 month fallow) at the High Plains Agricultural Laboratory near Sidney, NE, in 1993 and 1994. Both years showed similar seed yield across this range of plant populations. Plant populations of 11 000 resulted in 1.2 oz larger heads, 300 more seeds/head, 0.0004 oz larger seed, and 2 lb/bu lower test weight than populations of 20 000 plants/acre. Sunflower has the ability to compensate for wide population differences to maintain uniform seed yield. Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June. Gross income was reduced by $0.76/acre for each day of delay in planting after 25 May. Research Question Producers of sunflower in western Nebraska have limited information on appropriate planting dates and seeding rates to obtain optimum seed yield and oil percentage. This research attempts to determine the optimum planting date and population of sunflower. Literature Summary Sunflower is primarily grown for its oil. The price of oil influences the price of the crop, as it is based on both seed yield and oil percentage. A 2% price premium is given by the buyers for each percentage point the oil content increases between 40 and 45%; however, a 2% price discount is also taken for oil content for each point decrease between 40 and 38% and a larger penalty as oil percentage decreases further. Producers should be interested in both seed yield and oil percentage to maximize gross income. At Bushland, TX, the number of days from planting to the 50% ray flower stage (R 5.5) decreased with delayed planting. Yields were not different when planting from late March to mid‐June, but decreased when planting after 21 June. Oil yield per acre decreased when planting after 29 May. Sunflower adjusts to thin populations by increasing head and seed size. Populations higher than 15 000 plants/acre produce more oil‐containing seeds and have a higher bushel weight than lower populations. Also, populations above 15 000 plants/acre have smaller heads that remain more upright and dry faster than large heads; however, lower populations with larger heads and thicker stems usually lodge less than high populations. Study Description Environments: Irrigated (supplemental water following a previous crop of corn), dryland stubble (following wheat the previous year) and dryland fallow (following 22 mo fallow) Planting dates: 1993–25 May, 10 June, 28 June 1994–25 May, 13 June, 28 June Populations: 11 000, 14 000, 17 000 and 20 000 plants/acre Hybrids: ‘Pioneer 707’, ‘Sigco 475’ Applied Question What effect do planting dates have on the seed yield and oil percentage of sunflower? Seed yield and oil percentage declined as planting dates were delayed (Fig. ). Seed yield was reduced 6 lb/acre for each day delay in planting after 25 May. Gross income, which is based on seed yield and oil percentage, was reduced $0.76/acre for each day as planting was delayed after 25 May. What effect do populations have on the seed yield and oil percentage of sunflower? Sunflower oil percentage and seed yield for three planting dates averaged over three environments each year, 1993–.1994. image There was no difference in seed yield due to the range of sunflower populations evaluated. Sunflower yield is the product of (i) number of heads per acre, (ii) number of seeds/head, and (iii) weight per seed. Sunflower population, that is, plants per acre can also be defined as number of heads per acre, because most hybrids have a single head per plant. A negative relation of these components with population resulted in similar yields for this range of populations. As population increased, oil percentage increased, but the increase was not enough to have an impact on oil yield. What is the optimum population a farmer should use to plant sunflower? The cost of hybrid seed and availability of precision planting equipment encourage fanners to decide which population best meets their requirement. There was no benefit in seed yield or oil yield to populations greater than 12 000 plants/acre if weeds are controlled. If a producer has problems controlling weeds, a higher population could be used to help suppress weeds in sunflower. At low populations, sunflower heads are larger and dry more slowly, which could cause harvest difficulties. There is also a greater chance of soil erosion due to wind in fields where the population of sunflower is lower than 15 000 plants/acre. Problems associated with weed competition, head size, and wind erosion potential can be minimized by increasing the population of sunflower to 15 000 plants/acre or more.
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Claims 17
Claim · model-written summary
Seed yield was similar across tested populations.
- Taxon
- Sunflower
Helianthus annuust0 - Treatment
- this range of plant populationse0
- Outcome
- seed yielde0
- Direction
- similare0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Both years showed similar seed yield across this range of plant populations.”
Claim · model-written summary
At 11,000 plants per acre, heads were 1.2 oz larger than at 20,000.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- Plant populations of 11 000e0
- Outcome
- headse0
- Direction
- largere0
- Value
- 1.2 oze0
- Comparator
- populations of 20 000 plants/acree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Plant populations of 11 000 resulted in 1.2 oz larger heads, 300 more seeds/head, 0.0004 oz larger seed, and 2 lb/bu lower test weight than populations of 20 000 plants/acre.”
Claim · model-written summary
At 11,000 plants per acre, heads had 300 more seeds than at 20,000.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- Plant populations of 11 000e0
- Outcome
- seeds/heade0
- Direction
- moree0
- Value
- 300e0
- Comparator
- populations of 20 000 plants/acree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Plant populations of 11 000 resulted in 1.2 oz larger heads, 300 more seeds/head, 0.0004 oz larger seed, and 2 lb/bu lower test weight than populations of 20 000 plants/acre.”
Claim · model-written summary
At 11,000 plants per acre, seeds were 0.0004 oz larger than at 20,000.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- Plant populations of 11 000e0
- Outcome
- seede0
- Direction
- largere0
- Value
- 0.0004 oze0
- Comparator
- populations of 20 000 plants/acree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Plant populations of 11 000 resulted in 1.2 oz larger heads, 300 more seeds/head, 0.0004 oz larger seed, and 2 lb/bu lower test weight than populations of 20 000 plants/acre.”
Claim · model-written summary
At 11,000 plants per acre, test weight was 2 lb/bu lower than at 20,000.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- Plant populations of 11 000e0
- Outcome
- test weighte0
- Direction
- lowere0
- Value
- 2 lb/bue0
- Comparator
- populations of 20 000 plants/acree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Plant populations of 11 000 resulted in 1.2 oz larger heads, 300 more seeds/head, 0.0004 oz larger seed, and 2 lb/bu lower test weight than populations of 20 000 plants/acre.”
Claim · model-written summary
May 25 planting gave 200 lb higher seed yield per acre than June 28 planting.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- planted on 25 Maye0
- Outcome
- seed yielde0
- Direction
- highere0
- Value
- 200 lbe0
- Comparator
- planted on 28 Junee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June.”
Claim · model-written summary
May 25 planting gave 0.0003 oz higher weight per seed.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- planted on 25 Maye0
- Outcome
- weight per seede0
- Direction
- highere0
- Value
- 0.0003 oze0
- Comparator
- planted on 28 Junee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June.”
Claim · model-written summary
May 25 planting gave 0.5 oz higher weight per head.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- planted on 25 Maye0
- Outcome
- weight per heade0
- Direction
- highere0
- Value
- 0.5 oze0
- Comparator
- planted on 28 Junee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June.”
Claim · model-written summary
May 25 planting gave 2% higher oil.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- planted on 25 Maye0
- Outcome
- oile0
- Direction
- highere0
- Value
- 2%e0
- Comparator
- planted on 28 Junee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June.”
Claim · model-written summary
May 25 planting gave 100 lb/acre more oil.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- planted on 25 Maye0
- Outcome
- oile0
- Direction
- moree0
- Value
- 100 lb/acree0
- Comparator
- planted on 28 Junee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June.”
Claim · model-written summary
May 25 planting gave 2 lb/bu higher test weight.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- planted on 25 Maye0
- Outcome
- test weighte0
- Direction
- highere0
- Value
- 2 lb/bue0
- Comparator
- planted on 28 Junee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Sunflower planted on 25 May resulted in 200 lb higher seed yield per acre, 0.0003 oz higher weight per seed, 0.5 oz higher weight per head, 2% higher oil, 100 lb/acre more oil, and 2 lb/bu higher test weight than sunflower planted on 28 June.”
Claim · model-written summary
Gross income declined $0.76 per acre per day of planting delay after May 25.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- delay in planting after 25 Maye0
- Outcome
- Gross incomee0
- Direction
- reducede0
- Value
- $0.76/acree0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Gross income was reduced by $0.76/acre for each day of delay in planting after 25 May.”
Claim · model-written summary
Seed yield declined 6 lb per acre for each day of planting delay after May 25.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- delay in planting after 25 Maye0
- Outcome
- Seed yielde0
- Direction
- reducede0
- Value
- 6 lb/acree0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“Seed yield was reduced 6 lb/acre for each day delay in planting after 25 May.”
Claim · model-written summary
Oil percentage rose with population.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- population increasede0
- Outcome
- oil percentagee0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“As population increased, oil percentage increased, but the increase was not enough to have an impact on oil yield.”
Claim · model-written summary
The population-driven oil percentage increase did not affect oil yield.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- population increasede0
- Outcome
- oil yielde0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“As population increased, oil percentage increased, but the increase was not enough to have an impact on oil yield.”
Claim · model-written summary
Populations above 12,000 plants per acre did not benefit seed yield with weed control.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- populations greater than 12 000 plants/acree0
- Outcome
- seed yielde0
- Direction
- no benefite0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“There was no benefit in seed yield or oil yield to populations greater than 12 000 plants/acre if weeds are controlled.”
Claim · model-written summary
Populations above 12,000 plants per acre did not benefit oil yield with weed control.
- Taxon
- SunflowerHelianthus annuust0
- Treatment
- populations greater than 12 000 plants/acree0
- Outcome
- oil yielde0
- Direction
- no benefite0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Sunflower”
e0“There was no benefit in seed yield or oil yield to populations greater than 12 000 plants/acre if weeds are controlled.”
The same questions in other papers
sowing time · yield · Helianthus annuus (common sunflower)Positive and negative results
13 papers in the same direction as this paper · 39 in the opposite direction
- positive
- positive
- positive
49 papers more in this group
See all 53 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.