What Influences Manganese Availability in Turfgrass? Soil pH.Soil pH has a big impact on the solubility of Manganese in turfgrass. This is because the solubility of Mn falls by 100* for every unit increase in the soil pH. The converse occurs as soil pH decreases.As the soil pH increases Mn becomes less available. High OM, sandy and overlimed soils are all potentially likely to have this issue. Manganese is less available in high pH soils. At a high soil pH Calcium and Magnesium dominate exchange sites leaving no space for Mn. Mn is much more soluble and available to plants in acid soils (pH <5.5).In low pH soils, Mn can become toxic.You are likely too see Mn toxicity where Mn is present in low pH soils, there is a high OM content, soil minerals contain Mn, and the soil tends to be waterlogged.Soil Aeration.In aerated soils, Manganese is less available. In wet soils it is more available. Organic Matter.As soil OM increases, exchangeable Mn decreases, and in high OM soils with a soil pH > 6.5 you often see Mn deficiency.Many turf managers often add organic amendments to their turf. In this situation applications of OM tend to reduce Mn availability as it binds to this additional organic matter. You often see low levels of soil oxygen in wet soils, and soils with a combination of high soil OM levels plus warm temperatures. These conditions favour microbial activity that reduces the supply of oxygen.This fall in soil oxygen means that the oxide form of soil Manganese reduces to the soluble Manganese (Mn++) form. This increase in soluble Manganese causes an increase in the amount of plant available Manganese.The result is that a waterlogged soil is more prone to Mn toxicity. Iron Levels.High tissue iron levels tend to limit the uptake of Manganese in turf and cause a deficiency.
About Gilba Solutions
Gilba Solutions Pty Ltd are Sydney based independent sports turf consultants and turfgrass agronomists. We operate in Sydney, NSW, and the ACT.
Jerry Spencer has written over 100 articles & a book on turf nutrition. These are on topics ranging from turf fertilisers & aquatic weed management to using turf pigments & why turf herbicides sometimes don’t work. He also publishes a turf blog.
The Role Of Manganese in
Turfgrass
Nutrient Use
Manganese helps with the
uptake and utilisation of nutrients
like N and P
Root growth and Nutrient
uptake
Root growth, elongation and
lateral growth
Enhances Nutrient uptake
Iron Uptake
Helps Iron uptake and
distribution
Enzyme Activation
Is a cofactor for many enzymes
Crucial for enzyme activation &
functions.
Plant Defence
Influences the metabolism of
plant defence compounds
Helps turf resist pathogens
Stress Tolerance and anti-
oxidants
Manganese is important in the
activity of antioxidant enzymes
Reduces the damage caused
by reactive oxygen species
(ROS)
Nitrogen metabolism
Manganese plays a role in the
conversion of ammonia to
urea
Helps with the uptake and
utilisation of N
Chlorophyll Production
Manganese contributes to
chlorophyll synthesis and
production
Helps facilitate electron transfer
during the light dependent
reactions of photosynthesis
The Role of Manganese in Turfgrass
Carbohydrate Metabolism
Plays a role in sugar and
starch metabolism
Influences the breakdown and
uptake of carbohydrates
Cell Growth
Influences cell growth
Maintains cell function and
ensures optimal growth
Turfgrass
Nutrient Use
Manganese helps with the
uptake and utilisation of nutrients
like N and P
Root growth and Nutrient
uptake
Root growth, elongation and
lateral growth
Enhances Nutrient uptake
Iron Uptake
Helps Iron uptake and
distribution
Enzyme Activation
Is a cofactor for many enzymes
Crucial for enzyme activation &
functions.
Plant Defence
Influences the metabolism of
plant defence compounds
Helps turf resist pathogens
Stress Tolerance and anti-
oxidants
Manganese is important in the
activity of antioxidant enzymes
Reduces the damage caused
by reactive oxygen species
(ROS)
Nitrogen metabolism
Manganese plays a role in the
conversion of ammonia to
urea
Helps with the uptake and
utilisation of N
Chlorophyll Production
Manganese contributes to
chlorophyll synthesis and
production
Helps facilitate electron transfer
during the light dependent
reactions of photosynthesis
The Role of Manganese in Turfgrass
Carbohydrate Metabolism
Plays a role in sugar and
starch metabolism
Influences the breakdown and
uptake of carbohydrates
Cell Growth
Influences cell growth
Maintains cell function and
ensures optimal growth