Abstract
Deep-rooted crops used in rotation can improve the overall water and N use efficiencies of cropping systems and help minimize nitrate leaching to groundwater. Safflower ( Carthamus tinctorius L.) is a deep-rooted annual crop grown in Mediterranean regions that might be useful for this purpose. Safflower's response to residual soil N measured to 2.7 m in the soil profile was evaluated in 1998 in field plots in the San Joaquin Valley, California, USA that were used previously for cotton over a 9-year period and had been fertilized with nine N rates from 0 to 230 kg N/ha. Residual soil NO 3 -N measured prior to safflower planting increased with prior cotton fertilization rates. Amounts present to a soil profile depth of 2.7 m varied from 760 to 2600 kg/ha. Safflower seed yield increased with increasing pre-plant residual NO 3 -N levels, from 1700 kg/ha in the control to 2200 kg/ha, and then declined to 1800 kg/ha at the largest residual N level. Oil per cent, and oil yield were affected by soil N only at the largest residual N level, while oil composition was not affected. Root growth and N uptake at depth increased in plots with larger amounts of residual N compared to those with less. Results suggest that N fertilization applied to safflower could be reduced or even eliminated following crops previously fertilized at economic levels. Residual N should be accounted in growers' management programmes.
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Claims 5
Claim · model-written summary
Residual soil NO 3 -N before safflower planting increased with prior cotton fertilization rates.
- Taxon
- safflower
Carthamus tinctoriust0 - Treatment
- prior cotton fertilization ratese1
- Outcome
- residual soil NO 3 -Ne1
- Direction
- increasede1
- Value
- 760 to 2600 kg/hae2
- Setting
- San Joaquin Valley, California, USAe3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Response of safflower (Carthamus tinctorius L.) to residual soil N”
e1“Residual soil NO 3 -N measured prior to safflower planting increased with prior cotton fertilization rates”
e2“Amounts present to a soil profile depth of 2.7 m varied from 760 to 2600 kg/ha”
e3“field plots in the San Joaquin Valley, California, USA”
Claim · model-written summary
Safflower seed yield increased with increasing pre-plant residual NO 3 -N, reaching 2200 kg/ha compared with 1700 kg/ha in the control.
- Taxon
- safflowerCarthamus tinctoriuse4
- Treatment
- pre-plant residual NO 3 -N levelse4
- Outcome
- seed yielde4
- Direction
- increasede4
- Value
- 2200 kg/hae4
- Qualifier
- 1700 kg/hae4
- Comparator
- controle4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Response of safflower (Carthamus tinctorius L.) to residual soil N”
e4“Safflower seed yield increased with increasing pre-plant residual NO 3 -N levels, from 1700 kg/ha in the control to 2200 kg/ha”
Claim · model-written summary
Safflower seed yield declined to 1800 kg/ha at the largest residual N level.
- Taxon
- safflowerCarthamus tinctoriuse4
- Treatment
- largest residual N levele5
- Outcome
- seed yielde4
- Direction
- declinede5
- Value
- 1800 kg/hae5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Response of safflower (Carthamus tinctorius L.) to residual soil N”
e4“Safflower seed yield increased with increasing pre-plant residual NO 3 -N levels, from 1700 kg/ha in the control to 2200 kg/ha”
e5“and then declined to 1800 kg/ha at the largest residual N level”
Claim · model-written summary
Oil percent and oil yield of safflower were affected by soil N only at the largest residual N level.
- Taxon
- safflowerCarthamus tinctoriust0
- Treatment
- largest residual N levele6
- Outcome
- Oil per cent, and oil yielde6
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Response of safflower (Carthamus tinctorius L.) to residual soil N”
e6“Oil per cent, and oil yield were affected by soil N only at the largest residual N level”
Claim · model-written summary
Oil composition of safflower was not affected by residual soil N.
- Taxon
- safflowerCarthamus tinctoriust0
- Treatment
- residual soil Nt0
- Outcome
- oil compositione7
- Direction
- not affectede7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Response of safflower (Carthamus tinctorius L.) to residual soil N”
e7“while oil composition was not affected”
The same questions in other papers
nitrogen · yield · Carthamus tinctorius (safflower)Results differ
4 papers in the same direction as this paper · 36 in the opposite direction
- positive
- positive
- no effect
37 papers more in this group
See all 41 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.