Troubleshooting Corn

22 Feb

Troubleshooting Corn

By Corn 0 Comments

Magnesium, an Essential Plant Nutrient

  • Mobile within the plant Critical for several functions:
  • Central element in the chlorophyll molecule
  • Transport of phosphorus
  • Enzyme activation
  • Nutrient uptake functions
  • Oil and fat production
  • Translocation of starch

Magnesium Deficiency Symptoms

  • Often confused with other nutrient inadequacies May be positively identified by:
  • Visual and physiological symptoms
  • Soil chemical analysis
  • Plant mineral (tissue) analysis
  • Visual and Physiological Symptoms:
  • Interveinal chlorosis (yellow to white)
  • Necrotic edges
  • Purpling of the lower (older) leaves
  • Interveinal beading
  • Shorting of the internodes (in severe cases)

Favorable Conditions

  • Soil Physical and Chemical Properties That May Favor Magnesium Deficiencies:
  • Low cation exchange capacity (CEC) (sandy/silty soils)
  • Low to moderate pH (< 6.5)
  • High cation levels K+, NH4+, Na+, Ca2+, Al3+, Fe2+
  • Low soil temperatures
  • Highly permeable soils with excessive soil moisture
  • It may take more than one of the specific situations above to induce magnesium deficiency
  • Soil is a dynamic system and can change rapidly – spatially and temporally
  • Magnesium deficiencies can be dependent on year-to-year or month-to-month changes in growing conditions or fertilizer additions (K+, NH4+) 

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