Screening of wheat (Triticum aestivum) variesties tolerant to manganese- deficency stress

Abstract

Manganese deficiency is a problem in bread wheat (Triticum aestivum L. emend. Fiori & Paol.) production when
grown on highly permeable sandy soils cropped with rice (Oryza sativa L.) for 5 or more years. The variation in the
ability of wheat varieties to maintain yield on soils with limited Mn availability was investigated. A field experiment
was conducted during winter season (rabi) 1995-96 to study tbe tolerance of6 varieties of wheat to manganese stress
in a Mn-deficient field containing 2.2 mg DTPA-Mn/kg soil. The treanments included control and 3 foliar sprays of
0.5% manganese sulphate solution. All the varieties responded to foliar application of Mn and tbe increase in grain
yield varied from 0.30 to 0.85 tonnes/ha. The macaroni (Triticum durum Desf.) varieties of wheat responded more to
Mn (26.4-34.9%) than the Triticum aestivum varieties (7.9-23.0%). Based on tbe increase (%) in grain yield on foliar
application of Mn, the varieties were grouped least tolerant (,PBW 34' and 'PDW 215'), moderately tolerant (,PBW
226' and 'PBW 343') and tolerant (,WH 542' and 'HD 2329'). The grain yield was significantly related with both Mn
concentration in flag-leaf (r = 0.80*) and Mn uptake (r = 0.92**).