Abstract
Direct application of fertilizers in irrigation water (fertigation) is an efficient method of supplying nutrients to fruit trees. Information is needed on the relationship between irrigation and N inputs on N availability in order to target nutrient applications to meet plant demands. Soil solution was collected from permanently installed suction lysimeters and NO 3- N concentration was measured over the growing season in three experiments: 1) comparison of sprinkler irrigation + broadcast fertilizer with weekly fertigation + daily drip irrigation; 2) comparison of (NH 4 ) 2 SO 4 or Ca(NO 3 ) 2 as N sources under daily fertigation; and 3) comparisons of combinations of irrigation applied at either fixed rates or to meet evaporative demand and fertilizer (Ca(NO 3 ) 2 ) applied daily either at fixed rates or to maintain a given concentration in the fertigation solution in two soil types—loamy sand and silt loam. Trials are located in high density apple plantings of either `Gala' or `Empire' apple ( Malus × domestica Borkh.) on M.9 rootstock. Nitrate-N concentration in the soil solution measured at 30 cm deep remained higher, over more of the growing season, for weekly fertigation + daily drip irrigation than for a single broadcast fertilizer application + sprinkler irrigation. With daily Ca(NO 3 ) 2 fertigation, soil solution NO 3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added. Daily fertigation with (NH 4 ) 2 SO 4 resulted in less control of NO 3- N availability in the root-zone than with Ca(NO 3 ) 2 , which may be problematic for precise timing of N nutrition. Except for the fixed irrigation rate applied to the loamy sand soil, soil solution NO 3- N concentrations at 30 cm beneath the emitter were similar to average concentrations in the fertigating solution, for all methods of irrigation management in both soil types. Elevated NO 3- N concentrations in soil solution below the root zone (75 cm deep) were detected in the loamy sand regardless of methods of N application and irrigation although there was some evidence of less leaching to this depth, under scheduled irrigation. In the silt loam soil, considerably lower concentrations of NO 3- N were found beneath the root zone than at 30 cm deep for all of irrigation procedures and frequently there was insufficient water moving to 75 cm to provide sample. Tree growth in the loamy sand was less than in the silt loam soil; was limited by low application of irrigation water in 1992 and 1993; was unaffected by NO 3- N concentration in the root zone, indicating that N inputs could be minimized by adding N to maintain concentrations of 75 μg·mL -1 or possibly less. Nitrogen inputs may also be reduced if fertilizer N and irrigation water could be retained within the root zone. For coarse-textured soils this will require precise additions of water and possibly soil amendments to improve water holding capacity.
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Claims 16
Claim · model-written summary
Weekly fertigation with daily drip irrigation kept soil solution nitrate-N higher over more of the growing season than a single broadcast application with sprinkler irrigation in apple orchards.
- Taxon
- apple
Malus domesticae0 - Treatment
- weekly fertigation + daily drip irrigatione1
- Outcome
- Nitrate-N concentration in the soil solutione1
- Direction
- highere1
- Qualifier
- over more of the growing seasone1
- Comparator
- a single broadcast fertilizer application + sprinkler irrigatione1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e1“Nitrate-N concentration in the soil solution measured at 30 cm deep remained higher, over more of the growing season, for weekly fertigation + daily drip irrigation than for a single broadcast fertilizer application + sprinkler irrigation”
Claim · model-written summary
Daily Ca(NO3)2 fertigation increased soil solution NO3-N concentrations with the onset of fertigation.
- Taxon
- appleMalus domesticae0
- Treatment
- daily Ca(NO 3 ) 2 fertigatione2
- Outcome
- soil solution NO 3- N concentrationse2
- Direction
- increasede2
- Qualifier
- with the onset and end of fertigatione2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e2“With daily Ca(NO 3 ) 2 fertigation, soil solution NO 3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added”
Claim · model-written summary
Soil solution NO3-N concentrations decreased rapidly with the end of Ca(NO3)2 fertigation.
- Taxon
- appleMalus domesticae0
- Treatment
- daily Ca(NO 3 ) 2 fertigatione2
- Outcome
- soil solution NO 3- N concentrationse2
- Direction
- decreased rapidlye2
- Qualifier
- with the onset and end of fertigatione2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e2“With daily Ca(NO 3 ) 2 fertigation, soil solution NO 3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added”
Claim · model-written summary
Soil solution NO3-N concentrations remained relatively constant during the intervening period of daily Ca(NO3)2 fertigation.
- Taxon
- appleMalus domesticae0
- Treatment
- daily Ca(NO 3 ) 2 fertigatione2
- Outcome
- soil solution NO 3- N concentrationse2
- Direction
- no_changeinferrede2
- Qualifier
- during the intervening periode2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e2“With daily Ca(NO 3 ) 2 fertigation, soil solution NO 3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added”
Claim · model-written summary
Soil solution NO3-N concentrations were directly proportional to the amount of N added.
- Taxon
- appleMalus domesticae0
- Treatment
- amount of Ne2
- Outcome
- soil solution NO 3- N concentrationse2
- Direction
- increaseinferrede2
- Qualifier
- directly proportionale2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e2“With daily Ca(NO 3 ) 2 fertigation, soil solution NO 3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added”
Claim · model-written summary
Soil solution NO3-N concentrations were directly proportional to the amount of irrigation water added.
- Taxon
- appleMalus domesticae0
- Treatment
- amount of irrigation watere2
- Outcome
- soil solution NO 3- N concentrationse2
- Direction
- increaseinferrede2
- Qualifier
- directly proportionale2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e2“With daily Ca(NO 3 ) 2 fertigation, soil solution NO 3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added”
Claim · model-written summary
Daily fertigation with (NH4)2SO4 gave less control of root-zone NO3-N availability than Ca(NO3)2 fertigation in apple.
- Taxon
- appleMalus domesticae0
- Treatment
- Daily fertigation with (NH 4 ) 2 SO 4e3
- Outcome
- control of NO 3- N availability in the root-zonee3
- Direction
- lesse3
- Comparator
- Ca(NO 3 ) 2e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e3“Daily fertigation with (NH 4 ) 2 SO 4 resulted in less control of NO 3- N availability in the root-zone than with Ca(NO 3 ) 2”
Claim · model-written summary
Soil solution NO3-N concentrations at 30 cm beneath the emitter were similar to the average concentrations in the fertigating solution across irrigation management methods, except at the fixed rate on loamy sand.
- Taxon
- appleMalus domesticae0
- Treatment
- methods of irrigation managemente4
- Outcome
- soil solution NO 3- N concentrations at 30 cm beneath the emittere4
- Direction
- similare4
- Qualifier
- Except for the fixed irrigation rate applied to the loamy sand soile4
- Comparator
- average concentrations in the fertigating solutione4
- Setting
- both soil typese4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e4“Except for the fixed irrigation rate applied to the loamy sand soil, soil solution NO 3- N concentrations at 30 cm beneath the emitter were similar to average concentrations in the fertigating solution, for all methods of irrigation management in both soil types”
Claim · model-written summary
NO3-N concentrations below the root zone (75 cm deep) were elevated in the loamy sand regardless of N application and irrigation methods.
- Taxon
- appleMalus domesticae0
- Outcome
- NO 3- N concentrations in soil solution below the root zone (75 cm deep)e5
- Qualifier
- regardless of methods of N application and irrigatione5
- Setting
- loamy sande5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e5“Elevated NO 3- N concentrations in soil solution below the root zone (75 cm deep) were detected in the loamy sand regardless of methods of N application and irrigation”
Claim · model-written summary
In silt loam soil, NO3-N concentrations beneath the root zone were considerably lower than at 30 cm deep for all irrigation procedures.
- Taxon
- appleMalus domesticae0
- Treatment
- irrigation procedurese6
- Outcome
- concentrations of NO 3- Ne6
- Direction
- lowere6
- Comparator
- at 30 cm deepe6
- Setting
- silt loam soile6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e6“In the silt loam soil, considerably lower concentrations of NO 3- N were found beneath the root zone than at 30 cm deep for all of irrigation procedures”
Claim · model-written summary
Tree growth in the loamy sand was less than in the silt loam soil.
- Taxon
- appleMalus domesticae0
- Outcome
- Tree growthe7
- Direction
- lesse7
- Comparator
- silt loam soile7
- Setting
- loamy sande7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e7“Tree growth in the loamy sand was less than in the silt loam soil; was limited by low application of irrigation water in 1992 and 1993”
Claim · model-written summary
Tree growth was limited by low irrigation water application in 1992 and 1993.
- Taxon
- appleMalus domesticae0
- Treatment
- low application of irrigation watere7
- Outcome
- Tree growthe7
- Direction
- limitede7
- Setting
- 1992 and 1993e7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e7“Tree growth in the loamy sand was less than in the silt loam soil; was limited by low application of irrigation water in 1992 and 1993”
Claim · model-written summary
Tree growth was unaffected by NO3-N concentration in the root zone.
- Taxon
- appleMalus domesticae0
- Treatment
- NO 3- N concentration in the root zonee1
- Outcome
- Tree growthe7
- Direction
- no_changeinferrede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e7“Tree growth in the loamy sand was less than in the silt loam soil; was limited by low application of irrigation water in 1992 and 1993”
e1“was unaffected by NO 3- N concentration in the root zone, indicating that N inputs could be minimized by adding N to maintain concentrations of 75 μg·mL -1 or possibly less”
Claim · model-written summary
N inputs in apple could be minimized by adding N to maintain NO3-N concentrations of 75 μg·mL -1 or possibly less.
- Taxon
- appleMalus domesticae0
- Outcome
- N inputs could be minimizede1
- Value
- 75 μg·mL -1e1
- Qualifier
- maintain concentrations of 75 μg·mL -1 or possibly lesse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e1“was unaffected by NO 3- N concentration in the root zone, indicating that N inputs could be minimized by adding N to maintain concentrations of 75 μg·mL -1 or possibly less”
Claim · model-written summary
Nitrogen inputs in apple may be reduced if fertilizer N and irrigation water are retained within the root zone.
- Taxon
- appleMalus domesticae0
- Outcome
- Nitrogen inputs may also be reducede2
- Qualifier
- if fertilizer N and irrigation water could be retained within the root zonee2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e2“Nitrogen inputs may also be reduced if fertilizer N and irrigation water could be retained within the root zone”
Claim · model-written summary
Coarse-textured soils under apple will require precise water additions and possibly soil amendments to improve water holding capacity.
- Taxon
- appleMalus domesticae0
- Outcome
- precise additions of water and possibly soil amendmentse3
- Qualifier
- to improve water holding capacitye3
- Setting
- coarse-textured soilse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high density apple plantings of either `Gala' or `Empire' apple”
e3“For coarse-textured soils this will require precise additions of water and possibly soil amendments to improve water holding capacity”
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