Symptoms
Mn deficient plants show chlorotic spots and streaks which turn brown/gray-white, coalesce and may expand over the older leaves. Strongly affected leaf blades bend.
Reasons
Manganese deficiency
It is characteristic that Mn deficiency chlorosis occurs in irregular patches within the stand. The chlorotic mottling is seen first on youngest fully expanded leaves.
The susceptibility for manganese deficiency raises with high pH, high humus content, loose soil structure.
Often occurs in early spring as it is too cold for manganese deoxidizing bacteria.