Aluminium
aluminum is one of the primary factors that reduce the growth of plants on acidic soils. In acid soils the concentration of toxic Al3+ cations increases and disturbs the growth and function of the root. It is generally harmless to plant growth in pH-neutral soils. Wheat has developed a tolerance to aluminum. It releases organic compounds that bind to harmful aluminum cations. Sorghum is thought to have the same method of tolerating aluminum.