Abstract
Abstract Organic fertilizers are significantly lower in N content than chemical fertilizers, yet they can offer opportunities for efficient N utilization in lettuce ( Lactuca sativa L.) production. A 2‐yr split‐split plot trial was conducted in the growing seasons of 2018 and 2019 at South Deerfield, MA, to evaluate the effect of source and rate of N fertilizers on yield, and quality of two lettuce cultivars. Nitrogen sources including blood meal (BLM), dehulled soybean meal (DSM), dehydrated cow manure (DCM), and urea (URE) were the main plots. Nitrogen application rates of 0, 60, 120, and 180 kg N ha –1 were subplots and two lettuce cultivars with different morphological phenotypes of iceberg (‘Mighty Joe’) and leaf lettuce (‘Bergam's Green’) were sub‐subplots. Quadratic model explained lettuce yield response to N fertilizer rate, regardless of cultivar and N source. Among all N sources, DCM resulted in the least total N, nitrate‐N, ammonium‐N, and the lowest fresh lettuce yield (24.0 Mg ha –1 ) compared with URE (30.1 Mg ha –1 ), DSM (30.7 Mg ha –1 ) and BLM (28.7 Mg ha –1 ). Lettuce N requirement at maximum yield was 157.7, 171.4, 112.5, and 191.7 kg ha –1 for BLM, DSM, DCM, and URE, respectively. An increase in N application rate increased total N, nitrate‐N, and ammonium‐N but decreased agronomic efficiency and apparent N recovery. Incidence of lettuce tipburn and head decay was cultivar specific and was not influenced by N source. We concluded that DSM could be used as an organic fertilizer source that provides N similar to that of URE for lettuce production.
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Claims 14
Claim · model-written summary
A quadratic model explained lettuce yield response to N fertilizer rate regardless of cultivar and N source.
- Taxon
- lettuce
Lactuca sativat0 - Treatment
- N fertilizer ratee1
- Outcome
- yield response to N fertilizer ratee1
- Qualifier
- regardless of cultivar and N sourcee1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e1“Quadratic model explained lettuce yield response to N fertilizer rate, regardless of cultivar and N source”
Claim · model-written summary
DCM gave a lower fresh lettuce yield (24.0 Mg ha –1) than URE (30.1 Mg ha –1).
- Taxon
- lettuceLactuca sativat0
- Treatment
- DCMe2
- Outcome
- fresh lettuce yielde2
- Direction
- loweste2
- Value
- 24.0 Mg ha –1e2
- Qualifier
- 30.1 Mg ha –1e2
- Comparator
- UREe2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e2“Among all N sources, DCM resulted in the least total N, nitrate‐N, ammonium‐N, and the lowest fresh lettuce yield (24.0 Mg ha –1 ) compared with URE (30.1 Mg ha –1 ), DSM (30.7 Mg ha –1 ) and BLM (28.7 Mg ha –1 )”
Claim · model-written summary
DCM gave a lower fresh lettuce yield (24.0 Mg ha –1) than DSM (30.7 Mg ha –1).
- Taxon
- lettuceLactuca sativat0
- Treatment
- DCMe2
- Outcome
- fresh lettuce yielde2
- Direction
- loweste2
- Value
- 24.0 Mg ha –1e2
- Qualifier
- 30.7 Mg ha –1e2
- Comparator
- DSMe2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e2“Among all N sources, DCM resulted in the least total N, nitrate‐N, ammonium‐N, and the lowest fresh lettuce yield (24.0 Mg ha –1 ) compared with URE (30.1 Mg ha –1 ), DSM (30.7 Mg ha –1 ) and BLM (28.7 Mg ha –1 )”
Claim · model-written summary
DCM gave a lower fresh lettuce yield (24.0 Mg ha –1) than BLM (28.7 Mg ha –1).
- Taxon
- lettuceLactuca sativat0
- Treatment
- DCMe2
- Outcome
- fresh lettuce yielde2
- Direction
- loweste2
- Value
- 24.0 Mg ha –1e2
- Qualifier
- 28.7 Mg ha –1e2
- Comparator
- BLMe2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e2“Among all N sources, DCM resulted in the least total N, nitrate‐N, ammonium‐N, and the lowest fresh lettuce yield (24.0 Mg ha –1 ) compared with URE (30.1 Mg ha –1 ), DSM (30.7 Mg ha –1 ) and BLM (28.7 Mg ha –1 )”
Claim · model-written summary
DCM gave the least total N, nitrate-N and ammonium-N of all N sources.
- Taxon
- lettuceLactuca sativat0
- Treatment
- DCMe2
- Outcome
- total N, nitrate‐N, ammonium‐Ne2
- Direction
- leaste2
- Comparator
- all N sourcese2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e2“Among all N sources, DCM resulted in the least total N, nitrate‐N, ammonium‐N, and the lowest fresh lettuce yield (24.0 Mg ha –1 ) compared with URE (30.1 Mg ha –1 ), DSM (30.7 Mg ha –1 ) and BLM (28.7 Mg ha –1 )”
Claim · model-written summary
Lettuce N requirement at maximum yield was 157.7 kg ha–1 for BLM.
- Taxon
- lettuceLactuca sativat0
- Treatment
- BLMe3
- Outcome
- N requirement at maximum yielde3
- Value
- 157.7e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e3“Lettuce N requirement at maximum yield was 157.7, 171.4, 112.5, and 191.7 kg ha –1 for BLM, DSM, DCM, and URE, respectively”
Claim · model-written summary
Lettuce N requirement at maximum yield was 171.4 kg ha–1 for DSM.
- Taxon
- lettuceLactuca sativat0
- Treatment
- DSMe3
- Outcome
- N requirement at maximum yielde3
- Value
- 171.4e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e3“Lettuce N requirement at maximum yield was 157.7, 171.4, 112.5, and 191.7 kg ha –1 for BLM, DSM, DCM, and URE, respectively”
Claim · model-written summary
Lettuce N requirement at maximum yield was 112.5 kg ha–1 for DCM.
- Taxon
- lettuceLactuca sativat0
- Treatment
- DCMe3
- Outcome
- N requirement at maximum yielde3
- Value
- 112.5e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e3“Lettuce N requirement at maximum yield was 157.7, 171.4, 112.5, and 191.7 kg ha –1 for BLM, DSM, DCM, and URE, respectively”
Claim · model-written summary
Lettuce N requirement at maximum yield was 191.7 kg ha–1 for URE.
- Taxon
- lettuceLactuca sativat0
- Treatment
- UREe3
- Outcome
- N requirement at maximum yielde3
- Value
- 191.7e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e3“Lettuce N requirement at maximum yield was 157.7, 171.4, 112.5, and 191.7 kg ha –1 for BLM, DSM, DCM, and URE, respectively”
Claim · model-written summary
An increase in N application rate increased total N, nitrate-N and ammonium-N in lettuce.
- Taxon
- lettuceLactuca sativat0
- Treatment
- N application ratee4
- Outcome
- total N, nitrate‐N, and ammonium‐Ne4
- Direction
- increasede4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e4“An increase in N application rate increased total N, nitrate‐N, and ammonium‐N”
Claim · model-written summary
An increase in N application rate decreased agronomic efficiency and apparent N recovery in lettuce.
- Taxon
- lettuceLactuca sativat0
- Treatment
- N application ratee5
- Outcome
- agronomic efficiency and apparent N recoverye5
- Direction
- decreasede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e5“An increase in N application rate increased total N, nitrate‐N, and ammonium‐N but decreased agronomic efficiency and apparent N recovery”
Claim · model-written summary
Incidence of lettuce tipburn and head decay was specific to cultivar.
- Taxon
- lettuceLactuca sativat0
- Outcome
- Incidence of lettuce tipburn and head decaye6
- Qualifier
- cultivar specifice6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e6“Incidence of lettuce tipburn and head decay was cultivar specific”
Claim · model-written summary
N source did not influence incidence of lettuce tipburn and head decay.
- Taxon
- lettuceLactuca sativat0
- Treatment
- N sourcee7
- Outcome
- Incidence of lettuce tipburn and head decaye6
- Direction
- not influencede7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e6“Incidence of lettuce tipburn and head decay was cultivar specific”
e7“was not influenced by N source”
Claim · model-written summary
The authors conclude that DSM could be used as an organic fertilizer source for lettuce that provides N similar to URE.
- Taxon
- lettuceLactuca sativat0
- Treatment
- DSMe0
- Outcome
- could be used as an organic fertilizer sourcee0
- Qualifier
- provides N similar to that of UREe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce yield”
e0“DSM could be used as an organic fertilizer source that provides N similar to that of URE for lettuce production”
The same questions in other papers
fertilization · yield · Lactuca sativa (garden lettuce)Positive and negative results
35 papers in the same direction as this paper · 213 in the opposite direction
- positive
- positive
- no effect
245 papers more in this group
See all 249 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.