Phenotypic Differences in Accumulation


Historical Information
  Determination of Essentiality
Function in Plants
  Metabolic Processes
  Fruit Yield and Quality
Diagnosis of Magnesium Status in Plants
  Symptoms of Deficiency and Excess
    - Symptoms of Deficiency
    - Symptoms of Excess
  Environmental Causes of Deficiency Symptoms
  Nutrient Imbalances and Symptoms of Deficiency
    - Potassium and Magnesium
    - Calcium and Magnesium
    - Nitrogen and Magnesium
    - Sodium and Magnesium
    - Iron and Magnesium
    - Manganese and Magnesium
    - Zinc and Magnesium
    - Phosphorus and Magnesium
    - Copper and Magnesium
    - Chloride and Magnesium
    - Aluminum and Magnesium
  Phenotypic Differences in Accumulation
  Genotypic Differences in Accumulation
Concentrations of Magnesium in Plants
  Magnesium Constituents
    - Distribution in Plants
    - Seasonal Variations
    - Physiological Aspects of Magnesium Allocation
  Critical Concentrations
    - Tissue Magnesium Concentration Associations with Crop Yields
    - Tabulated Data of Concentrations by Crops
Assessment of Magnesium in Soils
  Forms of Magnesium in Soils
  Sodium Absorption Ratio
  Soil Tests
  Tabulated Data on Magnesium Contents in Soils
    - Soil Types
Fertilizers for Magnesium
  Kinds of Fertilizers
  Effects of Fertilizers on Plant Growth
  Application of Fertilizers
The uptake and accumulation of magnesium may change during different stages of physiological development. Knowledge of these changes is important in managing nutritional regimes for plant growth and for sampling of plants to assess their nutritional status. In poinsettias, magnesium accumulation was greatest from the period of flower induction to the visible bud stage, but then accumulation decreased during the growth phase of visible bud to anthesis (130). With cotton (Gossypium hirsutum L.), maximum daily influx of magnesium into roots occurred at peak bloom (175). Accumulation (net influx) of magnesium in annual ryegrass (Lolium multiflorum Lam.) decreased with increasing plant age (176,177). Similarly, magnesium uptake rates by tomato decreased from 68 to 17.5 � eq g-1 fresh weight per day as the plants aged from 18 to 83 days (110).

With anthurium (Anthurium andraeanum Lind.), changes in the allocation of magnesium to different organs with increased plant age were attributed to transport of nutrients from lower leaves to the flowers, resulting in a lowering of magnesium concentrations in the lower leaves (178). Tobacco (Nicotiana tabacum L.) showed decreasing concentrations of leaf magnesium from base to top of the plants over the growing season, and stem magnesium concentrations also fell with plant age (179). Sadiq and Hussain (180) attributed the decline in magnesium concentration in bean (Phaseolus vulgaris L.) plants to a dilution effect from plant growth. However, Jiménez et al. (181) reported no significant differences in shoot-tissue magnesium concentrations throughout the different growth stages of different soybean cultivars.