Apple

{Malus sylvestris}
Brown spots associated with boron deficiency.

Spotting a Boron Deficiency

Brown spots associated with boron deficiency.

Apple Brown Spots with Peeled Flesh

Spotting a Boron Deficiency

Brown spots associatated with boron deficiency. Note that the spots continue through from the surface into the flesh.

Bad apple with brown spots

Spotting a Boron Deficiency

Brown spots associatated with boron deficiency.

Boron deficient fruit on the left, regular fruit on right.

Spotting a Boron Deficiency

Boron-deficient fruit on the left, regular fruit on right.

Comparison of the inside of deficient and healthy apples

Spotting a Boron Deficiency

Brown spots caused by boron deficieny (right) are evident inside fruit as well as on surface.

Malformed Apple with Brown Spots

Spotting a Boron Deficiency

Malformed fruit and brown spots caused by boron deficiency.

Apple cracking and brown malformed fruit

Spotting a Boron Deficiency

Cracking and brown malformed fruit caused by boron deficiency.

Boron Deficiency in Apples

Boron deficiency commonly causes cracking and external cork symptoms on the fruit even though there may be no symptoms on the foliage, such as rosetting of thickened brittle leaves and dieback of the growing points. Premature fruit drop occurs and fruit quality can be badly impaired by the cork formation. When the internal cork develops early in the season, the affected fruit will become badly deformed.

In severe cases, dead areas appear in the bark of young branches (apple measles). The bark may be rough and cracked. Boron deficiency may affect the translocation of calcium in the tree, and in this way boron deficiency may be associated with “bitter pit.”

Soil Application (Suggested rates of application)

  Granubor 2 Fertibor
LBS./ACRE 7-21 7-21
KG/HA 7.88 - 23.63 7.88 - 23.63

Foliar Application (Suggested rates of application)

  Solubor
LBS./ACRE 0.5-1
KG/HA 0.5625 - 1.125

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