Agriculture Reference
In-Depth Information
Table 6.3
Leaves analysis guide for diagnosing micronutrient status of citrus adult trees. (Legaz
et al.
1995
)
Ranges (dry matter basis; ppm)
Deficient
Low
Optimum
High
Excess
Fe
3560
61-100
101-200
< 35
> 200
Zn
14-25
26-70
71-300
< 14
> 300
Mn
< 12
12-25
26-60
61-250
> 250
B
21-30
31-100
101-260
< 21
> 260
Cu
< 3
3-5
6-14
15-25
> 25
Mo
0.06-0.09
0.10-3.0
3.1-100
< 0.06
> 100
Table 6.4
Leaves analysis guide for diagnosing macronutrient status of citrus adult trees. (Legaz
et al.
1995
)
Ranges (dry matter basis; %)
Deficient
Low
Optimum
High
Excess
Sweet orange
N
< 230
2.30-2.50
2.51-2.80
2.81-3.00
> 3.00
P
0.10-0.12
0.13-0.16
0.17-0.20
< 0.10
> 0.20
K
0.50-0.70
0.71-1.00
1.01-1.30
< 0.50
> 1.30
Clementine Mandarin
N
2.21-2.40
2.41-2.70
2.71-2.90
< 2.20
> 2.90
P
0.09-0.11
0.12-0.15
0.16-0.19
< 0.09
> 0.19
K
< 0.50
0.50-0.70
0.71-1.00
1.01-1.30
> 1.30
Satsuma Mandarin
N
2.40-2.60
2.61-2.90
2.91-3.10
< 2.40
> 3.10
P
< 0.10
0.10-0.12
0.13-0.16
0.17-0.20
> 0.20
K
0.40-0.60
0.61-0.90
0.91-1.15
< 0.40
> 1.15
All species
Ca
1.60-2.90
3.00-5.00
5.10-6.50
< 1.60
> 6.50
Mg
0.15-0.24
0.25-0.45
0.46-0.90
< 0.15
> 0.90
S
0.14-0.19
0.20-0.30
0.31-0.50
< 0.14
> 0.51
lost from the soil. Clementine mandarins are very prone to Zn and Mn deficien-
cies, whereas Navel oranges demand high amounts of N. Accordingly, a number of
studies regarding fertilization programmes have been carried out (Embleton et al.
1973
; Legaz and Primo-Millo
1988
). We present a fertilizer programme by Legaz
and Primo-Millo (
1988
) (Table
6.5
), and a yearly distribution of a macronutrients
fertigation programme for the Spanish Mediterranean Area (Table
6.6
).
Cultural Practices
In most citrus producing countries, grafting is a common practice and is performed
by placing a number of buds on suitable scaffold branches with the purpose that the
foliage renewal occurs as soon as possible. It is an expensive cultural practice be-
cause it involves about two crops and around 4 years until the tree reaches its former
size. During the changing process care must be taken with pruning, irrigation and
