Soil Nutrient management
Micronutrients
Manganese
The primary form of manganese uptake is manganous ion (Mn2+). Other ionic forms (Mn⁺, Mn4+) may also exist under varying soil physical and chemical conditions.
Manganese, like many other micronutrients, is immobile in plants. This is an important point because it means that deficiency symptoms will first appear on younger leaves since the plant cannot easily scavenge manganese from older tissue. Most crops deficient in manganese become yellowish to olive green.
Manganese toxicity is not likely to occur on most soils except those that are extremely acidic when the soil pH is less than 5.0.
Manganese is a fairly mobile element in soil and can be leached, particularly on sandy soils. Manganese availability depends on soil pH, organic matter, and waterlogging. Manganese deficiency is highly unlikely on soils that have a pH below 6.8, but become toxic at pH below 5.0. On the other hand, it may be deficient on calcareous soils or on soils that have been over limed.
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