Plants absorb manganese through their roots in sub-acid and neutral pH soil conditions, like Mn2+.
It's maximum concentration can be found near the meristems and all the highly active metabolic tissues. It has also a relation with vitamin metabolism.
Together with magnesium it acts as an activator of many enzymes: in fact it plays an important role in the Krebs cycle, avoiding accumulation of organic acids, that beyond a certain threshold, cause damage to cell walls. It is therefore linked to photosynthesis in the plant and allows a correct sugar fixation and therefore accumulation in the fruits.
It has also a fundamental role in the lipid metabolism, catalysing the production of some of their precursors. For this reason it is necessary for the constitution of the cell membranes, basic structures for the plants' survival: manganese deficiency appear as a leaf yellowing due to a lack of chloroplast synthesis.
Also amino acid synthesis has a relation with manganese: it catalyses the peptidase for the organication of nitrates and nitrites.
INN Manga PS a water soluble powder formulation based on monohydrate manganese sulphate with 32 % manganese.
INN Manga Chel a water soluble powder formulation based on manganese chelated with EDTA with 13% manganese.