Nutrients

N Nitrogen
P Phosphorus
K Potassium
Mg Magnesium
Ca Calcium
S Sulfur
B Boron
Cu Copper
Fe Iron
Mn Manganese
Mo Molybdenum
Zn Zinc

Soybean - Necrosis

Symptoms
Beginning on older leaves, numerous small brown spots give the plant a mottled appearance. Furthermore, the blotches expand and coalesce to irregularly shapened, light brown necrosis.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Soybean - Chlorosis

Symptoms
Interveinal yellow chlorosis, starting on the older leaf margins. The main veins remain green for some time.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Soybean - Chlorosis

Symptoms
Interveinal yellow chlorosis, starting on the older leaf margins. The main veins remain green for some time. As the yellowing progresses towards the leaf base, there appear brown marginal necroses.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Soybean - Chlorosis

Symptoms
Interveinal yellow chlorosis, starting on the older leaf margins. The main veins remain green for some time. As the yellowing progresses towards the leaf base, there appear brown marginal necroses. They may drie off and form a necrotic seam all along the leaf edge.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Soybean - Chlorosis

Symptoms
Interveinal yellow chlorosis, starting on the older leaf margins. The main veins remain green for some time. As the yellowing progresses towards the leaf base, there appear brown necrotic spots in the marginal area.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Soybean - Chlorosis

Symptoms
Already far advanced chlorosis. The leaf is almost completely bleached, only the midrib and the adjacent area are still green. As the chlorosis progresses towards the leaf base, there appear brown necrotic spots in the marginal area.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Soybean - Deformation

Symptoms
Already far advanced chlorosis. The leaf is almost completely bleached, only the leaf base, the midrib and its adjacent area are still green. As the chlorosis progresses towards the leaf base, there appear brown necrotic spots in the marginal area. Leaves are bent down.

Reasons
Potassium deficiency. Large amounts of K are necessary for adequate nutrition of soybeans.

Potassium deficiency made worse by

  • Acidic soils (low pH)
  • Sandy or light soils (leaching)
  • Drought conditions
  • High rainfall (leaching)
  • or heavy irrigation
  • Heavy clay (illite) soils
  • Soils with low K reserves
  • Magnesium rich soils

Potassium is important for

  • Increased activation of enzymes and co-enzyme functions
  • Improved protein synthesis
  • Better stomatal function, turgor potential

Yara recommended fertilizers for Potassium

NUTRA-PHOS Zn-K PLUS

NUTRA-PHOS Zn-K PLUS

Soya Bean: 2 to 10 lb. per acre per application. First application at bud to early-bloom stage, repeat in 2 to 3 weeks. Apply aerial applications in at least 5 gallons/acre and ground applications in at least 10 gallons/acre; however, when total application gallonage is 25 gallons per acre or less, DO NOT mix more than 1 lb. of this product per gallon of water.

Read more about NUTRA-PHOS Zn-K PLUS