Boron toxicity

[Home] Insect and mite pests ] Diseases ] Nematodes ] Environmental Causes ] Nutrient disorders ] [Glossary ]


Yellowing between leaves, brown lesions and downward cupping of older leaves are symptoms of  B toxicity (J. O'Sullivan). 

Diagnostic summary

  • What you see on plants

- older leaves develop conspicuous necrotic spots in interveinal areas, usually preceded by pale patches.

- affected leaves tend to cup downward (cultivars with deeply divided leaf shape may cup upward)

- affected leaves eventually turn yellow and fall off.

  • Most likely to occur on saline and alkaline soils, or following the application of irrigation water high in boron.

Characteristics and occurrence


Confusion with other symptoms

Diagnostic  tests




View full fact sheet