Abstract
Abstract Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.). The level of NO 3 -N in petioles of recently mature leaves was a good indicator of the seasonal N status for pumpkins on irrigated sand, and to a lesser degree for pumpkins on dryland loam. Petiole NO 3 -N concentrations decreased with time and with decreasing N rate at both sites, with the rate and extent of decrease considerably greater on the irrigated sand. The optimum time of sampling was at about initial fruit set or early fruiting. Critical (10% yield reduction) and minimum sufficiency (lowest concentration before yield reduction) levels for petiole NO 3 -N at early fruiting were estimated at 6300 and 8000 μg·g −1 , respectively, in dryland and 4000 and 6700 μg·g −1 , respectively, for irrigated plantings. Deficiency symptoms were associated with NO 3 -N concentrations <1500 μg·g −1 . Soil NO 3 -N levels proved unsatisfactory as a NO 3 -N index in dryland soil, but meaningful relationships ( R 2 = 0.31) were obtained between fruit yield and soil NO 3 -N on irrigated sand. Fertilizer N requirements for 90% and 100% of marketable yield were estimated at 44 and 158 kg N/ha for dryland and 125 and 225 kg N/ha for irrigated pumpkins, respectively. However, N fertilizer rates of 202 and 269 kg N/ha delayed harvest 9 days on irrigated sand and 15 days on dryland loam, compared to lower N rates.
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Claims 19
Claim · model-written summary
Petiole NO3-N was a good indicator of seasonal N status for pumpkins on irrigated sand.
- Organ / stage
- petioles of recently mature leavese1
- Compound
- NO 3 -Ne1
- Outcome
- seasonal N statuse1
- Setting
- irrigated sande1
CucurbitaNot reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“The level of NO 3 -N in petioles of recently mature leaves was a good indicator of the seasonal N status for pumpkins on irrigated sand, and to a lesser degree for pumpkins on dryland loam”
Claim · model-written summary
Petiole NO3-N was a lesser indicator of seasonal N status for pumpkins on dryland loam.
- Organ / stage
- petioles of recently mature leavese1
- Compound
- NO 3 -Ne1
- Outcome
- seasonal N statuse1
- Setting
- dryland loame1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“The level of NO 3 -N in petioles of recently mature leaves was a good indicator of the seasonal N status for pumpkins on irrigated sand, and to a lesser degree for pumpkins on dryland loam”
Claim · model-written summary
Petiole NO3-N concentrations decreased with time at both sites.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e3“Petiole NO 3 -N concentrations decreased with time and with decreasing N rate at both sites, with the rate and extent of decrease considerably greater on the irrigated sand”
Claim · model-written summary
Petiole NO3-N concentrations decreased with decreasing N rate.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e3“Petiole NO 3 -N concentrations decreased with time and with decreasing N rate at both sites, with the rate and extent of decrease considerably greater on the irrigated sand”
Claim · model-written summary
The rate and extent of the petiole NO3-N decrease were considerably greater on irrigated sand.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e3“Petiole NO 3 -N concentrations decreased with time and with decreasing N rate at both sites, with the rate and extent of decrease considerably greater on the irrigated sand”
Claim · model-written summary
The optimum time of sampling petiole NO3-N for pumpkin was about initial fruit set or early fruiting.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e4“The optimum time of sampling was at about initial fruit set or early fruiting”
Claim · model-written summary
The critical petiole NO3-N level at early fruiting was 6300 in dryland.
- Organ / stage
- early fruitinge5
- Compound
- NO 3 -Ne5
- Outcome
- Critical (10% yield reduction)e5
- Value
- 6300e5
- Setting
- drylande5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e5“Critical (10% yield reduction) and minimum sufficiency (lowest concentration before yield reduction) levels for petiole NO 3 -N at early fruiting were estimated at 6300 and 8000 μg·g −1 , respectively, in dryland and 4000 and 6700 μg·g −1 , respectively, for irrigated plantings”
Claim · model-written summary
The minimum sufficiency petiole NO3-N level at early fruiting was 8000 in dryland.
- Organ / stage
- early fruitinge5
- Compound
- NO 3 -Ne5
- Outcome
- minimum sufficiencye5
- Value
- 8000e5
- Setting
- drylande5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e5“Critical (10% yield reduction) and minimum sufficiency (lowest concentration before yield reduction) levels for petiole NO 3 -N at early fruiting were estimated at 6300 and 8000 μg·g −1 , respectively, in dryland and 4000 and 6700 μg·g −1 , respectively, for irrigated plantings”
Claim · model-written summary
The critical petiole NO3-N level at early fruiting was 4000 for irrigated plantings.
- Organ / stage
- early fruitinge5
- Compound
- NO 3 -Ne5
- Outcome
- Critical (10% yield reduction)e5
- Value
- 4000e5
- Setting
- irrigated plantingse5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e5“Critical (10% yield reduction) and minimum sufficiency (lowest concentration before yield reduction) levels for petiole NO 3 -N at early fruiting were estimated at 6300 and 8000 μg·g −1 , respectively, in dryland and 4000 and 6700 μg·g −1 , respectively, for irrigated plantings”
Claim · model-written summary
The minimum sufficiency petiole NO3-N level at early fruiting was 6700 for irrigated plantings.
- Organ / stage
- early fruitinge5
- Compound
- NO 3 -Ne5
- Outcome
- minimum sufficiencye5
- Value
- 6700e5
- Setting
- irrigated plantingse5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e5“Critical (10% yield reduction) and minimum sufficiency (lowest concentration before yield reduction) levels for petiole NO 3 -N at early fruiting were estimated at 6300 and 8000 μg·g −1 , respectively, in dryland and 4000 and 6700 μg·g −1 , respectively, for irrigated plantings”
Claim · model-written summary
Deficiency symptoms in pumpkin were associated with NO3-N concentrations below 1500 μg·g −1.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e6“Deficiency symptoms were associated with NO 3 -N concentrations <1500 μg·g −1”
Claim · model-written summary
Soil NO3-N levels were unsatisfactory as an NO3-N index in dryland soil.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“Soil NO 3 -N levels proved unsatisfactory as a NO 3 -N index in dryland soil, but meaningful relationships ( R 2 = 0.31) were obtained between fruit yield and soil NO 3 -N on irrigated sand”
Claim · model-written summary
Fruit yield was related to soil NO3-N on irrigated sand, with R2 = 0.31.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“Soil NO 3 -N levels proved unsatisfactory as a NO 3 -N index in dryland soil, but meaningful relationships ( R 2 = 0.31) were obtained between fruit yield and soil NO 3 -N on irrigated sand”
Claim · model-written summary
Fertilizer N requirement for dryland pumpkin was 44 kg N/ha for 90% of marketable yield.
- Outcome
- Fertilizer N requirementse7
- Value
- 44e7
- Qualifier
- 90% and 100% of marketable yielde7
- Setting
- drylande7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“Fertilizer N requirements for 90% and 100% of marketable yield were estimated at 44 and 158 kg N/ha for dryland and 125 and 225 kg N/ha for irrigated pumpkins, respectively”
Claim · model-written summary
Fertilizer N requirement for dryland pumpkin was 158 kg N/ha for 100% of marketable yield.
- Outcome
- Fertilizer N requirementse7
- Value
- 158e7
- Qualifier
- 90% and 100% of marketable yielde7
- Setting
- drylande7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“Fertilizer N requirements for 90% and 100% of marketable yield were estimated at 44 and 158 kg N/ha for dryland and 125 and 225 kg N/ha for irrigated pumpkins, respectively”
Claim · model-written summary
Fertilizer N requirement for irrigated pumpkin was 125 kg N/ha for 90% of marketable yield.
- Outcome
- Fertilizer N requirementse7
- Value
- 125e7
- Qualifier
- 90% and 100% of marketable yielde7
- Setting
- irrigated pumpkinse7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“Fertilizer N requirements for 90% and 100% of marketable yield were estimated at 44 and 158 kg N/ha for dryland and 125 and 225 kg N/ha for irrigated pumpkins, respectively”
Claim · model-written summary
Fertilizer N requirement for irrigated pumpkin was 225 kg N/ha for 100% of marketable yield.
- Outcome
- Fertilizer N requirementse7
- Value
- 225e7
- Qualifier
- 90% and 100% of marketable yielde7
- Setting
- irrigated pumpkinse7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“Fertilizer N requirements for 90% and 100% of marketable yield were estimated at 44 and 158 kg N/ha for dryland and 125 and 225 kg N/ha for irrigated pumpkins, respectively”
Claim · model-written summary
N fertilizer rates of 202 and 269 kg N/ha delayed harvest by 9 days on irrigated sand compared with lower N rates.
- Treatment
- N fertilizer rates of 202 and 269 kg N/hae7
- Outcome
- harveste7
- Direction
- delayede7
- Value
- 9 dayse7
- Comparator
- lower N ratese7
- Setting
- irrigated sande7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“However, N fertilizer rates of 202 and 269 kg N/ha delayed harvest 9 days on irrigated sand and 15 days on dryland loam, compared to lower N rates”
Claim · model-written summary
N fertilizer rates of 202 and 269 kg N/ha delayed harvest by 15 days on dryland loam compared with lower N rates.
- Treatment
- N fertilizer rates of 202 and 269 kg N/hae7
- Outcome
- harveste7
- Direction
- delayede7
- Value
- 15 dayse7
- Comparator
- lower N ratese7
- Setting
- dryland loame7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Field experiments were conducted in 1985 and 1986 to determine in-season indexes for petiole NO 3 -N in dryland-grown and irrigated pumpkins ( Cucurbita moschata Poir.)”
e7“However, N fertilizer rates of 202 and 269 kg N/ha delayed harvest 9 days on irrigated sand and 15 days on dryland loam, compared to lower N rates”
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