Boron deficiency is a widespread agricultural concern, but certain global regions are particularly affected due to their predominant soil types, climate, and geological history.
South and Southeast Asia are among the most severely affected regions. In
Bangladesh, widespread boron deficiency has been documented across floodplain soils, where sandy alluvial deposits and intensive cropping deplete available boron. In
Pakistan, field surveys of calcareous alkaline soils have found 35 to 56 percent of agricultural fields to be boron deficient.
Sub-Saharan Africa faces extensive boron deficiency linked to highly weathered
Ferralsols and
Acrisols that have undergone intense leaching over geological timescales. Countries across West Africa and East Africa report low soil boron levels affecting cereal and legume production. In
South America, the
Cerrado region of
Brazil is particularly vulnerable due to its acidic, highly weathered
Oxisols with low organic matter content. Boron deficiency is a recognized constraint for soybean, eucalyptus, and coffee cultivation in these soils.
Northern and Western Europe experience boron deficiency primarily in leached sandy and
podzolic soils, particularly in
Scandinavia, the
Baltic states, and parts of the
United Kingdom. These soils have low cation exchange capacity and organic matter, leading to boron leaching under high rainfall conditions.
Arid and semi-arid regions with calcareous soils, such as parts of the
Middle East, northern
Africa, and the
Mediterranean Basin, also exhibit boron deficiency. Although total soil boron may be adequate, high soil pH and calcium carbonate content reduce plant-available boron through adsorption and precipitation reactions. ==Boron requirements==