Abstract
Canola ( Brassica napus L.) yield is often limited by heat and water stress. Early seeding may avoid the heat and water stress at critical growth stages but will encounter low soil temperatures and frequent frosts. Three experiments were performed at two locations in Montana from 2002 to 2004 to determine (i) early spring seeding effect on seed yield and oil content and optimum seeding rates for early seeding, (ii) base temperature (T b ) for germination and heat requirement for emergence, and (iii) suitable cultivars for early spring seeding. Late‐March‐seeded canola yielded 0 to 5% greater than mid‐April seeding. Delaying seeding from mid‐April to mid‐May resulted in 43 to 63% yield reduction. Oil content was 12 to 22 g kg −1 greater for mid‐May seeding than mid‐April seeding in 3 out of 5 site‐year combinations. A seeding rate of 32 to 65 seeds m −2 was found sufficient to produce optimum yields. Oil content tended to decrease 10 to 20 g kg −1 when seeding rate increased from 11 to 97 seeds m −2 . The T b for germination was less than 4°C, and the growing degree days for 50% emergence (GDD 50 ) were 42 to 81. Yield was negatively correlated ( r = −0.46 to −0.65) to the days to 50% flowering, and biomass measured at 60 d after planting was negatively correlated to the chlorophyll fluorescence ratio (F v /F m ) after cold stress ( r = −0.58). The optimal seeding period for the region is between late March and mid‐April. Several genotypes were found to have favorable characteristics for early seeding.
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Claims 11
Claim · model-written summary
Late-March-seeded canola yielded 0 to 5% more than mid-April seeding.
- Taxon
- canola
.jpg?width=60)
Brassica napus var. napuse1 - Treatment
- Late‐March‐seedede1
- Outcome
- yielde1
- Direction
- greatere1
- Value
- 0 to 5%e1
- Comparator
- mid‐April seedinge1
- Setting
- Montanae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Three experiments were performed at two locations in Montana from 2002 to 2004”
e1“Late‐March‐seeded canola yielded 0 to 5% greater than mid‐April seeding”
Claim · model-written summary
Delaying seeding from mid-April to mid-May reduced canola yield by 43 to 63%.
- Taxon
- canolaBrassica napus var. napust1
- Treatment
- Delaying seeding from mid‐April to mid‐Maye2
- Outcome
- yielde2
- Direction
- reductione2
- Value
- 43 to 63%e2
- Comparator
- mid‐Aprile2
- Setting
- Montanae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three experiments were performed at two locations in Montana from 2002 to 2004”
e2“Delaying seeding from mid‐April to mid‐May resulted in 43 to 63% yield reduction”
t1“Early Seeding Canola”
Claim · model-written summary
Oil content was 12 to 22 g kg -1 greater for mid-May seeding than for mid-April seeding in 3 of 5 site-year combinations.
- Taxon
- canolaBrassica napus var. napust1
- Treatment
- mid‐May seedinge3
- Outcome
- Oil contente3
- Direction
- greatere3
- Value
- 12 to 22 g kg −1e3
- Qualifier
- in 3 out of 5 site‐year combinationse3
- Comparator
- mid‐April seedinge3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“Oil content was 12 to 22 g kg −1 greater for mid‐May seeding than mid‐April seeding in 3 out of 5 site‐year combinations”
t1“Early Seeding Canola”
Claim · model-written summary
A seeding rate of 32 to 65 seeds m-2 was sufficient to produce optimum canola yields.
- Taxon
- canolaBrassica napus var. napust1
- Treatment
- seeding ratee4
- Outcome
- optimum yieldse4
- Value
- 32 to 65 seeds m −2e4
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e4“A seeding rate of 32 to 65 seeds m −2 was found sufficient to produce optimum yields”
t1“Early Seeding Canola”
Claim · model-written summary
Oil content tended to decrease by 10 to 20 g kg -1 when seeding rate increased from 11 to 97 seeds m-2.
- Taxon
- canolaBrassica napus var. napust1
- Treatment
- seeding ratee5
- Outcome
- Oil contente5
- Direction
- decreasee5
- Value
- 10 to 20 g kg −1e5
- Qualifier
- from 11 to 97 seeds m −2e5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e5“Oil content tended to decrease 10 to 20 g kg −1 when seeding rate increased from 11 to 97 seeds m −2”
t1“Early Seeding Canola”
Claim · model-written summary
The base temperature for germination of canola is less than 4°C.
- Taxon
- canolaBrassica napus var. napust1
- Outcome
- T b for germinatione6
- Value
- less than 4°Ce6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e6“The T b for germination was less than 4°C, and the growing degree days for 50% emergence (GDD 50 ) were 42 to 81”
t1“Early Seeding Canola”
Claim · model-written summary
Growing degree days for 50% emergence of canola were 42 to 81.
- Taxon
- canolaBrassica napus var. napust1
- Outcome
- growing degree days for 50% emergencee6
- Value
- 42 to 81e6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e6“The T b for germination was less than 4°C, and the growing degree days for 50% emergence (GDD 50 ) were 42 to 81”
t1“Early Seeding Canola”
Claim · model-written summary
Canola yield is negatively correlated with the days to 50% flowering (r = -0.46 to -0.65).
- Taxon
- canolaBrassica napus var. napust1
- Organ / stage
- 50% floweringe7
- Outcome
- Yielde7
- Direction
- negatively correlatede7
- Value
- r = −0.46 to −0.65e7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e7“Yield was negatively correlated ( r = −0.46 to −0.65) to the days to 50% flowering”
t1“Early Seeding Canola”
Claim · model-written summary
Biomass at 60 days after planting is negatively correlated with the chlorophyll fluorescence ratio after cold stress (r = -0.58).
- Taxon
- canolaBrassica napus var. napust1
- Treatment
- cold stresse0
- Outcome
- biomass measured at 60 d after plantinge0
- Direction
- negatively correlatede0
- Value
- r = −0.58e0
- Qualifier
- chlorophyll fluorescence ratio (F v /F m )e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“biomass measured at 60 d after planting was negatively correlated to the chlorophyll fluorescence ratio (F v /F m ) after cold stress ( r = −0.58)”
t1“Early Seeding Canola”
Claim · model-written summary
The optimal seeding period for the region is between late March and mid-April.
- Taxon
- canolaBrassica napus var. napust1
- Outcome
- optimal seeding periode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The optimal seeding period for the region is between late March and mid‐April”
t1“Early Seeding Canola”
Claim · model-written summary
Several canola genotypes have favorable characteristics for early seeding.
- Taxon
- canolaBrassica napus var. napust1
- Material
- genotypese0
- Outcome
- favorable characteristics for early seedinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Several genotypes were found to have favorable characteristics for early seeding”
t1“Early Seeding Canola”
The same questions in other papers
density · yield · Brassica napus (oilseed rape)Positive and negative results
53 papers in the same direction as this paper · 29 in the opposite direction · 3 reporting no difference from an alternative
- no effect
- positive
- negative
82 papers more in this group
See all 86 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.