This document discusses nutrition strategies for high density orchards in Italy. It addresses [1] maintaining high and constant production while preserving environmental quality, [2] understanding nutrient requirements based on soil type, climate and variety, and [3] optimizing fertilizer application rates and timing. Key factors discussed include monitoring leaf nutrient concentrations, nutrient uptake kinetics by trees, and balancing nutrient inputs and outputs to maximize efficiency and minimize losses from the system.

1. The role of nutrition in the development
of high density orchards in Italy
Moreno Toselli
Dipartimento Colture Arboree, University of Bologna
moreno.toselli@unibo.it

2. Objectives
• High and constant production
• High fruit quality
•Environment preservation

3. Foto S. Michele A. A:

4. features
• rate = tree request
• time of application
according to uptake kinetics
•Avoid deficiencies and excess
•Maximize nutrient efficiency

5. N deficiency

6. Knowledge
• environment of cultivation
(soil & climate)

7. Clay-Loam Sandy

8. Water vs N Leaching
4
3
NO3- N Flow Rate
3
(kg/day/ha)
2
R2 = 0.91
2
1
1
0
0 20 40 60 80
Water Flow Rate (tons/day/ha)

9. Sandy soil of North America

10. NO3-N (kg/ha)
0
10
20
30
40
50
30-Jan
18-Feb
05-Mar
19-Mar
01-Apr
15-Apr
28-Apr
13-May
28-May
10-Jun
24-Jun
N Leaching
Date
kg 140.7
08-Jul
22-Jul
05-Aug
19-Aug
02-Sep
16-Sep
30-Sep
21-Oct
04-Nov

11. Knowledge
• environment of cultivation
(soil & climate)
• genotype (rootstock &
variety)

13. Tagliavini e Malaguti

14. Trunks Gala/M9
cm
100 cm 135
100 cm
Root > 2mm
Tagliavini and Malaguti

15. Optimal leaf nutrient concentration in Emilia-
Romagna (Fuji)
nutrient Petal drop1 fruit set summer
(%)
N 3.4 - 3.9 2.4 - 2.8 2.4 - 2.7
P 0.2 - 0.35 0.18 - 0.3 0.15 - 0.3
K 1.2 - 1.8 1.2 - 1.7 0.8 - 1.4
Ca 0.8 - 1.3 1.0 - 1.3 1.2 - 1.6
Mg 0.2 - 0.3 0.25 - 0.3 0.2 - 0.4
: spur leaflets
1

16. Optimal leaf nutrient concentration in Emilia-
Romagna (Fuji)
nutrient Petal drop1 fruit set summer
(ppm)
Fe 100 - 150 70 -100 70 - 95
Mn 11 - 220 15 - 45 22 - 55
Cu 13 - 40 8 - 15 8 - 16
Zn 30 - 70 28 - 50 20 - 30
1
: spur leaflets

17. Leaf N concentration in Soth Tyrol of Italy
(Golden, Fuji, and others varieties)
4
Fuji - Ferrara
3
N (% SS)
2
1
0 50 100 150 200
gg. dopo la piena fioritura
Days after full bloom
(Stimpfl e Aichner, 2002)

18. P leaf concentration in S T of Italy (Golden, Fuji)
0.5
0.4 Fuji - Ferrara
P (% SS)
0.3
0.2
0.1
0
0 50 100 150 200
Days after la piena fioritura
gg. dopo full bloom
(Stimpfl e Aichner, 2002)

19. K leaf in S T of Italy (Golden, Fuji)
3
Fuji - Ferrara
2
K (% SS)
1
0
0 50 100 150 200
Days dopo la piena fioritura
gg. after full bloom
(Stimpfl e Aichner, 2002)

20. Knowledge
• Environment (soil and climate)
• Genotype (rootstock & variety)
• Nutrient request (amount and kynetics)

21. KEY QUESTIONS
• AMOUNT OF FERTILIZER
• APPLICATION TIME

22. + N Balance
-
SOURCE Uptaken
•Atmospheric • Leaves
•NH4+ adsorbed • pruning wood
•Irrigation water • permanent wood
•Fertilizers • Fruits
RISERVES LOST
•OM •Leackage
•Microbs •Volatilization

23. Fruits
Pruning biomass
(21) (17)
Fallen
leaves
(16)
skeleton
(6)
(60)
(data VI year
SOIL kg N/ha)

24. Fruits
(42) Pruning biomass
(11)
Fallen
leaves
(27)
Skeleton
(4)
(84)
(data VI year
SOIL kg K/ha)

25. Fruits
Pruning biomass
Fallen
leaves
Skeleton
Ca (kg Ca/ha) in 6
years
Soil

26. Amount of nutrients removed by apple trees after
6 years and partitioning to tree organs
nutrient total skeleton leaves pruning fruits
(kg/ha) (%) (%) % (%)
N 358 30 21 25
P 66 33 22 28
K 435 15 11 40
Ca 489 30 17 3
Mg 105 19 13 29

27. Nutrient removed by apple (kg/ha)
Organ N P K CaO MgO
Fruits 20 5 50 4 2
leaves 43 2.6 45 72 18
pruning 10 1.6 3 21 18
wood 15 3.4 12 36 2
others 10 1.2 12 3 1
Total 99 13.8 122 136 41
Disciplinari Provincia Trento., 1992

28. Removal (kg/ha)
SPECIE N P K Ca Mg
kiwifruit 130-140 15-20 100-110 200-235 10-12
cherry 90-100 10-20 85-100 90-95 15-18
Kaki 150-170 15-20 115-125 100-115 18-21
apple 40-90 10-20 115-150 120-135 18-21
pear 70-90 5-10 65-85 135-140 12-15
peach 90-150 10-20 100-150 110-130 21-24
grape 60-100 10-15 65-85 40-90 9-15
Scudellari, 1998

29. N uptake kinetics
species time % of N total
uptake
grape Before full bloom 25
Full bloom – veraison 50
Veraison – harvest 25
peach Before mid May 10
Mid May – end August 65
End August – leaf fall 25
plum Before April 15
May – end August 60
End August – leaf fall 25

30. approx 90-95% of leaf N comes from N
remobilization ( Neilsen et al., 1997 )

31. 18
Leaf N trend
16
14
12
10
8
N (mg/leaf)
6
pre-harvest 96
4
bloom97
2
0
8 29 72 94 115 143 178
Days after bloom

32. N accumulation in Mutsu apple
140
120
100
N (mg/fruit)
80
60
pre-harvest 96
40 bloom 97
20
29 72 94 115 143
Day after bloom

33. POTTED WALNUT
TIME OF NUE (%)
FERTILIZATION
7 days after End of trial
fertilization May 2008
Bud burst 4.19 66.4
Pistillate flower 21.6 60.0
Late summer 34.5 69.1
Significance * ns

34. SOIL N AVAILABILITY
NO3- - N (mg kg-1) *
soil volume (0.8 m*10000 m2) / 2
Soil apparent specific weigth
(1.2-1.4)
AVAILABILITY kg N/ha

36. Estimation of soil NO3- -N
1 ppm = 6 kg N/ha
10 ppm = 60 kg N/ha
20 ppm = 120 kg N/ha

37. N (kg/ha)
0
20
30
40
50
60
70
80
10
Darchini
Folli
Gasparri
Soil N
Miserocchi
Balella
Graziani
farm
Melandri
Applied N
Ragazzini
Fruit thinning
Calderoni
Bubani
Calderoni
Mongardi
Montanari
Frega
Zaffagnini

43. Compost, by-products
Ricycled organic waste

45. Heat
NH3 CO2
H2O
Mix of organic
O2 O2 Compost
compounds
(weight = 100) (weight < 50)
Organic matter
Stabilized O. M.
Carbohydrates, proteins, fats (easily degradable) partially humified
Cellulose, hemicelluloses (degradable)
Minerals
Lignin (slowly degradable)
Minerals Water
Water Microorganisms
Microorganisms

46. Organic fertilizer composition
COW
COMPOST
MANURE
D.W. (%) 33 82
O.M. (%) 42 47
N (% p.s.) 1.6 2.4
C (% p.s.) 27 23
C/N 17 10
Total P (% p.s.) 2.0 0.6
Total K (% p.s.) 2.4 0.9

48. 3
2.5
Total N (‰)
2
1.5
1
0.5
1 2 3 4 5 6
Soil OM (%)
Control Mineral CM spring
Compost spring Compost 5 Compost 10

52. TREE YIELD (kg)
TREATMENT 2004 2005 2006 2007 2008 2009 2010 2011 total
Control 31.8 46.3 56.4 b 38.0 b 25.7 b 69.7 44.5 49.9 353.3 b
Mineral 32.4 48.1 68.8 a 51.4 a 27.6 b 62.5 42.6 54.1 384.3 ab
Cow Manure 33.6 45.9 63.7 ab 39.8 b 32.5 ab 61.1 47.8 56.3 380.7 ab
Compost spring 32.9 50.2 60.2 ab 41.5 b 32.8 ab 62.6 49.7 53.2 383.0 ab
Compost 5 32.1 51.5 60.4 ab 40.2 b 25.6 b 62.5 47.7 54.1 370.6 ab
Compost 10 31.9 50.5 66.6 a 43.5 b 37.8 a 64.7 49.2 59.1 403.4 a
Significance n.s. n.s. ** * *** n.s. n.s. n.s. *

53. Bitter pit recorrence
• Genetic suskeptibility: Braeburn, Jonagold, Fuji, Stark D
• Low crop load
•Early or late harvest
• Nutrient antagonism: Ca vs K, Mg e NH4+
• Adverse environmental conditions for root growth (low
temp., soil moisture, drought stress, nutrient deficiency)
• High tree vigor (winter pruning, water and N high
availability)

55. Ca: 157 ppm Ca: 233
K: 8232 K: 7751
K/Ca: 54 K/Ca: 34
Bitter pit in Fuji

58. N, K and K released by leaves
120
N, K & Ca remaining
(% of initial content)
100
80 N
60
Ca
40
K
20
0
0 10 20 30 40 50 60 70 80 90 100 110
weeks Tagliavini et al., 2007

59. Ca and bitter pit
50
40
% fruit bitter pit
30
20
10
0
3 4 5 6 7 8 9
Ca (mg/100 g FW)
(Perring & Preston, 1974)

60. Flower pollination and fruit Ca
n. seeds/ Ca Mg K
fruit (ppm) (ppm) (%)
0-1 174 284 0,68
2-3 208 278 0,66
4-5 215 279 0,65
>5 223 280 0,66
( Bramlage et al., 1990)

61. Fruit Ca accumulation
12 Stage Recommended sprays
one
10
8
Ca (mg/fruit)
6
Gala
Spartan
4
Fuji
2
0
150 170 190 210 230 250 270 290
June July August September October
Neilsen et al., 2001

62. CaCl2 penetration in Golden D. fruit
45
120
100
80
Penetration (%)
60
40
20
0
0 20 40 60 80 100 120 140
Days after full bloom
(Schlegel e Schöenherr, 2002)

63. fertilizer POD Solubility weight
(%) (g l-1) (g mol-1)
CaCl2 . 6 H2O 33 2790 219
Ca(NO3)2 . 4 H2O 56 6600 236
NH4NO3 63 1183 80
KH2PO4 95 33 136
KNO3 95 133 101
Schönherr, 2002

64. At bud breack root uptake may be impaired and N
storage not sufficient

65. Leaf age
16 *
14
*
NDF uptake (mg m-2)
12 *
*
10
8
6 Apical
4 Basal
2
0
1 5 24 48 120
Ore

66. 19
%
www.ruhr-uni-bochum.de

67. Mg deficiency

68. Courtesy of Dr. Tagliavini

71. Pear
Mg Mn
Fertilizer (mg kg-1 ss) (mg kg-1 ss)
Control 0.34b 70a
Sulphate (0.48g/l) 0.38a 864c
Complexed 0.38a 716b
Significance *** *
N. Treatments
4 0.33 469
7 0.38 631
Significance *** *

72. Fertigation allows the
optimal fertilizer
distribution

73. Fertigation benefits:
 Nutrient application in the soil with the highest root
density
 Minimize the risk of deficiency or excess
 Increase mobility of nutrient such as K, P, Mg
 High nutrient efficiency = low rate = low leaching rate
(NO3-N)
 Low costs
 Low environmental impact

74. Clay soil loam soil sandy soil
pepperfriends.com netafimitalia.com

75. Fast and constant yield
• The restricted volume of soil wet by drip affect
tree physiology
• High number of secondary roots and root tips with
an increase of absorbing surface and root:soil
interface
• Higher nutrient and water uptake efficiency
• Increse synthesis of endogenous hormons like
Cytokinines and Gibberellins that promote flower
differentiation (Bravdo, 2000).

76. Critical points
 fertilizer: pure, soluble and mixable
 pH: 5.5-7, higher pH = Ca and Mg salt precipitation
 Concentration of the solution <2‰
 Sulphates react with Ca2+ to make gypsum
(CaSO4), that precipitate
 micronutrients (Fe & Zn) precipitate with
phosphates and carbonates

77. Water solubility

78. Fertilizer mixability

79. Apple fertigation
(kg/ha)
N P K Mg
APRIL 2 2.8 1.0 0
MAY 6 8.4 3.0 0
JUNE 15 2.3 8.2 5.9
JULY 15 4.9 24.3 3.0
AUGUST 10 4.8 32.0 1.1
SEPTEMBER 8 1.8 31.5 0
total 56 25 100 10

80. Conclusions
• Apple trees have low N requirement
• High K requiremenet
• Fertigation increases nutrient
efficiency
• Foliar sprays (N, Ca, Mg, K) can
increase nutrient efficiency
• Application of high quality composted
organic material is recommendable

83. N-NO3- (kg/ha)
0
2
4
6
8
10
12
14
21-May
03-Jun
18-Jun
02-Jul
16-Jul
30-Jul
13-Aug
27-Aug
Date
kg 51.7
10-Sep
24-Sep
08-Oct
22-Oct
Nitrate Leaching in 1996
05-Nov
19-Nov
03-Dec
17-Dec

85. Leaf applied N partitioning
Leaves Fruits Shoot Twigs Total
DW (g) 12.2 41.3 10.7 -
3.5
1.64 0.44 0.1 2.25
N (mg/organ)
15
0.08
73 19 5 100
N (%)
15
3

86. Salinity
Secndary salinization, application of salts with irrigation
Fertigation increases E.C., that must be <1,8dS/m