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Below is a cotton (Gossypium hirsutum 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 youngest fully expanded leaf, often the 4th or 5th from the top) and are derived from agricultural research, such as guidelines from the University of Georgia, Mississippi State University, and other cotton-growing regions, adjusted for cotton physiology.
Growth stages are categorized as:
- Vegetative (seedling to squaring)
- Reproductive (first square to first bloom)
- Boll Development (bloom to peak boll fill)
- Maturation (boll opening)
- 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 |
|
|
Vegetative |
4.00 |
5.00 |
0.30 |
0.60 |
2.50 |
3.50 |
0.30 |
0.60 |
1.00 |
2.00 |
0.30 |
0.50 |
|
Reproductive |
3.50 |
4.50 |
0.30 |
0.50 |
2.00 |
3.00 |
0.30 |
0.60 |
1.50 |
2.50 |
0.30 |
0.50 |
|
Boll Development |
3.00 |
4.00 |
0.20 |
0.50 |
2.00 |
3.50 |
0.30 |
0.70 |
2.00 |
3.00 |
0.20 |
0.40 |
|
Maturity |
2.50 |
3.50 |
0.20 |
0.30 |
1.50 |
2.50 |
0.30 |
0.60 |
2.00 |
3.00 |
0.20 |
0.40 |
|
Harvest |
2.00 |
3.00 |
0.20 |
0.30 |
1.50 |
2.50 |
0.20 |
0.50 |
1.50 |
2.50 |
0.15 |
0.30 |
|
B (ppm) |
Zn (ppm) |
Mn (ppm) |
Fe (ppm) |
Cu (ppm) |
Mo (ppm) |
|||||||
|
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
Min |
Max |
|
|
Vegetative |
20 |
40 |
20 |
60 |
30 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Reproductive |
25 |
50 |
20 |
60 |
30 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Boll Development |
30 |
60 |
20 |
60 |
30 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Maturity |
20 |
40 |
20 |
60 |
30 |
100 |
50 |
150 |
5 |
15 |
0.10 |
1.00 |
|
Harvest |
20 |
40 |
15 |
40 |
20 |
75 |
30 |
100 |
4 |
10 |
0.10 |
0.80 |
|
LWC |
BRIX |
|||||||||||
|
Min |
Max |
Min |
Max |
|||||||||
|
Vegetative |
85 |
90 |
8 |
12 |
||||||||
|
Reproductive |
80 |
88 |
10 |
15 |
||||||||
|
Boll Development |
78 |
85 |
12 |
18 |
||||||||
|
Maturity |
75 |
82 |
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.
