Calcium deficiency/ internal browning-Potatoes

Symptoms
Young shoot tips are deformed as the young leaflets are not developed properly. Remaining leaf stubs show dark brown necrosis. Calcium deficiency is seldom seen on the leaves, as most soils contains enough calcium for leaf growth.

Reasons
Calcium deficiency Boron deficiency causes similar symptoms, but necrosis is normally seen between the veins and not only at the edge of the leaf as with calcium deficiency. Potassium deficiency causes necrosis at the edge of the leaf, but symptoms are first visible on the older leaves. The leaves with potassium deficiency normally do not curl up.

Potatoes - Deformation

Symptoms
The margins of young, fully developed leaflets are cupped upwards. Calcium deficiency is seldom seen on the leaves, as most soils contain enough calcium for leaf growth.

Reasons
Calcium deficiency

Calcium deficiency/ internal browning made worse by

Acidic soils
Sandy or light soils (leaching)
Acid peat soils
Soils rich in sodium
Soils rich in aluminium
Drought conditions
Fruit high in nitrogen or potassium
Large fruit

Calcium is important for

Healthy green foliage
Improved yield and quality
Better storage potential of tubers

Yara recommended fertilizers for Calcium

YaraTera CALCINIT

Potatoes: Fertigate 250 Kg/ha between Hilling up and Tuber Initiation. Refer to Yara crop program @ www.yara.com.au as a guide or contact your local Yara sales agronomist for advice.

YaraLiva NITRABOR

Potatoes: Spread 150-200 Kg/ha before Hilling up. Contact your local Yara sales agronomist for advice.

UNIKA CALCIUM

Potatoes: Spread 200-250 Kg/ha at Tuber Initiation. Refer to Yara crop program @ www.yara.com.au as a guide or contact your local Yara sales agronomist for advice.