Abstract
The effects of cover crop, tillage, and N fertilization on yields of `Paladin' watermelon ( Citrullus lanatus ) were analyzed by determining available soil N levels, foliar N content, and relative greenness with a SPAD-502 chlorophyll meter. Analyses from all three analytical procedures identified N deficiencies in watermelon with their respected measurements. Available soil N analyses indicated that soil N levels below 40 mg·kg –1 at vining caused dramatic decreases in yields, while the level needed to ensure maximal yields during the same period was 100 mg·kg –1 . Results from foliar and SPAD tests indicated that plants with foliar N levels below 42 g·kg –1 and SPAD readings below 40 SPAD units at anthesis will have suppressed yields. Optimal foliar N levels and SPAD readings required for maximum yields were 50 g·kg –1 and 48 SPAD units, respectively. The main difference among all three N testing procedures was that available soil N analysis was able to detect possible deficiencies two to three weeks before either the foliar or SPAD analysis. Differences in yield between plants from conventionally tilled plots and no-till plots were not significant. However, inorganic N fertilization significantly increased yields in watermelon following both rye ( Secale cereale ) and mix cover crop treatments. Watermelon yields of plants following the hairy vetch ( Vicia villosa ) cover crop treatment showed no response to inorganic N fertilization. Of the three cover crop treatments, the addition of N fertilizer had the most effect in the rye treatment.
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Claims 13
Claim · model-written summary
All three tests identified nitrogen deficiency in watermelon.
- Taxon
- watermelon
Citrullus lanatuse0 - Outcome
- identified N deficienciese0
- Value
- three analytical procedurese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Analyses from all three analytical procedures identified N deficiencies in watermelon with their respected measurements”
Claim · model-written summary
Soil N below 40 mg·kg –1 at vining was associated with sharply lower yield.
- Taxon
- watermelonCitrullus lanatust0
- Organ / stage
- vininge0
- Compound
- soil Ne0
- Outcome
- yieldse0
- Direction
- decreasese0
- Value
- 40 mg·kg –1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“soil N levels below 40 mg·kg –1 at vining caused dramatic decreases in yields”
t0“Watermelons”
Claim · model-written summary
Soil N of 100 mg·kg –1 at vining was needed for maximal yield.
- Taxon
- watermelonCitrullus lanatust0
- Organ / stage
- vininge0
- Compound
- soil Ne0
- Outcome
- maximal yieldse0
- Direction
- maximale0
- Value
- 100 mg·kg –1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“soil N levels below 40 mg·kg –1 at vining caused dramatic decreases in yields, while the level needed to ensure maximal yields during the same period was 100 mg·kg –1”
t0“Watermelons”
Claim · model-written summary
Foliar N below 42 g·kg –1 at anthesis indicated suppressed yield.
- Taxon
- watermelonCitrullus lanatust0
- Organ / stage
- anthesise0
- Compound
- foliar Ne0
- Outcome
- suppressed yieldse0
- Direction
- suppressede0
- Value
- 42 g·kg –1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plants with foliar N levels below 42 g·kg –1 and SPAD readings below 40 SPAD units at anthesis will have suppressed yields”
t0“Watermelons”
Claim · model-written summary
SPAD reading below 40 at anthesis indicated suppressed yield.
- Taxon
- watermelonCitrullus lanatust0
- Organ / stage
- anthesise0
- Outcome
- suppressed yieldse0
- Direction
- suppressede0
- Value
- 40 SPAD unitse0
Not reportedSetting
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD readings below 40 SPAD units at anthesis will have suppressed yields”
t0“Watermelons”
Claim · model-written summary
Optimal foliar N for maximal yield was 50 g·kg –1.
- Taxon
- watermelonCitrullus lanatust0
- Compound
- foliar Ne0
- Outcome
- maximum yieldse0
- Direction
- maximume0
- Value
- 50 g·kg –1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Optimal foliar N levels and SPAD readings required for maximum yields were 50 g·kg –1 and 48 SPAD units, respectively”
t0“Watermelons”
Claim · model-written summary
Optimal SPAD reading for maximal yield was 48 units.
- Taxon
- watermelonCitrullus lanatust0
- Compound
- foliar Ne0
- Outcome
- maximum yieldse0
- Direction
- maximume0
- Value
- 48 SPAD unitse0
Not reportedSetting
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Optimal foliar N levels and SPAD readings required for maximum yields were 50 g·kg –1 and 48 SPAD units, respectively”
t0“Watermelons”
Claim · model-written summary
Soil N analysis detected possible deficiency two to three weeks earlier than foliar or SPAD analysis.
- Taxon
- watermelonCitrullus lanatust0
- Outcome
- detect possible deficienciese0
- Value
- two to three weekse0
- Comparator
- foliar or SPAD analysise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“available soil N analysis was able to detect possible deficiencies two to three weeks before either the foliar or SPAD analysis”
t0“Watermelons”
Claim · model-written summary
Yield did not differ significantly between conventional tillage and no tillage.
- Taxon
- watermelonCitrullus lanatust0
- Treatment
- conventionally tilled plotse0
- Outcome
- yielde0
- Direction
- not significante0
- Comparator
- no-till plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Differences in yield between plants from conventionally tilled plots and no-till plots were not significant”
t0“Watermelons”
Claim · model-written summary
Inorganic N fertilization significantly raised watermelon yield after rye cover crop.
- Taxon
- watermelonCitrullus lanatuse0
- Treatment
- inorganic N fertilizatione0
- Interactor
- rye
Secale cerealee0other - Outcome
- yieldse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“inorganic N fertilization significantly increased yields in watermelon following both rye ( Secale cereale ) and mix cover crop treatments”
Claim · model-written summary
Inorganic N fertilization significantly raised watermelon yield after mixed cover crop.
- Taxon
- watermelonCitrullus lanatuse0
- Treatment
- inorganic N fertilizatione0
- Outcome
- yieldse0
- Direction
- increasede0
- Qualifier
- mix cover crop treatmentse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“inorganic N fertilization significantly increased yields in watermelon following both rye ( Secale cereale ) and mix cover crop treatments”
Claim · model-written summary
Watermelon after hairy vetch showed no yield response to inorganic N fertilization.
- Taxon
- WatermelonCitrullus lanatuse0
- Treatment
- inorganic N fertilizatione0
- Outcome
- yieldse0
- Direction
- no responsee0
- Qualifier
- hairy vetch ( Vicia villosa ) cover crop treatmente0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Watermelon yields of plants following the hairy vetch ( Vicia villosa ) cover crop treatment showed no response to inorganic N fertilization”
Claim · model-written summary
Nitrogen fertilizer had its largest effect after rye cover crop.
- Taxon
- watermelonCitrullus lanatust0
- Treatment
- addition of N fertilizere0
- Outcome
- most effecte0
- Direction
- most effecte0
- Qualifier
- rye treatmente0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the addition of N fertilizer had the most effect in the rye treatment”
t0“Watermelons”
The same questions in other papers
fertilization · yield · Citrullus lanatus (watermelon)Results differ
88 papers in the same direction as this paper · 9 in the opposite direction · 2 reporting no difference from an alternative
- no effect
- no effect
- negative
96 papers more in this group
See all 100 papers →tillage · yield · Citrullus lanatus (watermelon)Positive and negative results
3 papers in the same direction as this paper · 7 reporting no difference from an alternative
- positive
- positive
- positive
7 papers more in this group
See all 11 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.