Severe magnesium deficiency can reduce yields by up to 15%. Regular use of magnesium on an annual basis has provided yield increases of 1 to 10% in trials. Adequate magnesium is needed during tuber bulking. If dry soil conditions restrict uptake, then foliar sprays can be very effective.
Trials in UK also show the effect magnesium has on yield.
Low levels of magnesium will reduce the starch content of tubers and protein levels that affect the taste of the cooked potato. Trials in Australia confirm the positive benefits of magnesium on specific gravity.
Magnesium also benefits tuber dry matter, as trials in Holland show.
Low magnesium levels can increase susceptibility to enzymatic discolouration, as studies in Katahdin (USA) show.
Uptake of magnesium is dependent upon the cation exchange capacity of the soil and its balance with the other cations, especially potassium. High concentrations of potassium in the soil can induce magnesium deficiency. In such cases, foliar applications of magnesium are beneficial.
|Magnesium at potato growth stages|
|Planting||For plant development|
|Tuber initiation||Bigger tubers|
|Bulking||Maintain tuber growth|