Poor quality underground irrigation water occurs in most arid and semiarid regions. This water contains not only excessive amounts of soluble salts but also fluoride (F) from traces to 30 mg/1 in India, but usually the concentration of F is below 5 mg/1 (Gupta, 1979). The effect of F on plants is not well known but plants accumulate it when it is present in the soil or applied through irrigation water. Singh, Chhabra & Abrol (1980) found that soil-applied F at 50 mg/kg was toxic to rice and 32 mg/kg tissue content of F was toxic to wheat. Paliwal (1972) found that F content in berseem increased from 18·1 to 52·7 mg/kg when the crop was irrigated with F contaminated water. He further found that 10 mg F/kg inhibited germination and growth of wheat seedlings, and whilst low concentrations of F may not be toxic to plants they may be hazardous to animals continuously fed on fodders containing fluoride.

The effect of fluoride-rich saline water on the yield and F content of fodder oats has therefore been determined.