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Below is a wheat (Triticum aestivum L.) tissue nutrient sufficiency table by growth stage, including macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium, sulfur), micronutrients (boron, copper, iron, manganese, zinc, molybdenum), leaf water content (LWC), and Brix values. These values are based on leaf tissue analysis (typically the flag leaf or uppermost fully expanded leaf) and are derived from agricultural research, such as guidelines from Kansas State University, University of Nebraska-Lincoln, and other wheat-growing regions, adjusted for wheat physiology.
Growth stages follow the Feekes scale, simplified into key phases:
- Feekes 1–5 (Vegetative, emergence to tillering)
- Feekes 6–10 (Stem Elongation, jointing to boot)
- Feekes 10.1–10.5 (Reproductive, heading to flowering)
- Feekes 11.1–11.4 (Grain Fill to Maturity, milk to ripening)
- Harvest
Nutrient concentrations are in percentages (%) for macronutrients and parts per million (ppm) for micronutrients, with LWC as a percentage of fresh weight and Brix (°Bx) as soluble solids in sap.
|
Growth Stage |
N (%) |
P (%) |
K (%) |
Mg (%) |
Ca (%) |
S (%) |
||||||
|
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
|
|
Feekes 1-5 |
4.00 |
5.00 |
0.30 |
0.50 |
2.50 |
3.50 |
0.20 |
0.40 |
0.20 |
0.50 |
0.20 |
0.40 |
|
Feekes 6-10 |
3.00 |
4.00 |
0.20 |
0.40 |
2.00 |
3.00 |
0.20 |
0.40 |
0.30 |
0.60 |
0.20 |
0.30 |
|
Feekes 10.1-10.5 |
2.00 |
3.00 |
0.20 |
0.40 |
1.70 |
2.50 |
0.20 |
0.40 |
0.30 |
0.60 |
0.20 |
0.30 |
|
Feekes 11.1-11.4 |
1.50 |
2.50 |
0.10 |
0.30 |
1.50 |
2.00 |
0.20 |
0.40 |
0.30 |
0.60 |
0.10 |
0.30 |
|
Harvest |
1.00 |
3.00 |
0.10 |
0.30 |
1.00 |
2.00 |
0.20 |
0.40 |
0.30 |
0.50 |
0.10 |
0.20 |
|
B (ppm) |
Zn (ppm) |
Mn (ppm) |
Fe (ppm) |
Cu (ppm) |
Mo (ppm) |
|||||||
|
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
|
|
Feekes 1-5 |
6 |
25 |
20 |
70 |
20 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Feekes 6-10 |
6 |
25 |
20 |
70 |
20 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Feekes 10.1-10.5 |
6 |
25 |
20 |
70 |
20 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Feekes 11.1-11.4 |
6 |
25 |
20 |
70 |
20 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Harvest |
5 |
20 |
15 |
50 |
20 |
75 |
30 |
100 |
4 |
10 |
0.10 |
0.80 |
|
LWC |
BRIX |
|||||||||||
|
Min |
Max |
Min |
Max |
|||||||||
|
Feekes 1-5 |
85 |
90 |
8 |
12 |
||||||||
|
Feekes 6-10 |
80 |
88 |
10 |
15 |
||||||||
|
Feekes 10.1-10.5 |
78 |
85 |
12 |
18 |
||||||||
|
Feekes 11.1-11.4 |
70 |
80 |
8 |
14 |
||||||||
|
Harvest |
70 |
78 |
8 |
12 |
||||||||
Scanning Recommendation:
- Ensure that over 25% of the scan bed is covered with a single layer of vegetation.
- Leaf selection should be similar to this illustration.
