Résumé :
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Two separate experiments, in clay loam and loamy sand (prepared by mixing the clay loam with washed sand), were performed to determine the effects of sowing method and sodicity on the survival, ion uptake, grain yield and yield components of spring wheat (Triticum aestivum L.) cv. Kharchia-65. Three sodicity levels (control, exchangeable sodium percentage (ESP) 5-7; low (ESP 18-20); high (ESP 39-40)) and four sowing methods (sowing dry and pre-germinated seed and transplanting of 16 and 21-day-old seedlings) were tested. In the control and at low sodicity, sowing method had no effect on plant survival, grain and straw dry weight per plant. However at high sodicity, these variables were lower in plants established from pre-germinated seed than in plants established from dry seed, the farmers' normal practice. In contrast, transplanted seedlings showed increased survival and had significantly higher grain and straw dry weight than plants established by solving dry seed. Differences in grain yield between sowing method and sodicity treatments were mainly due to differences in the number of grains per plant. Although increasing sodicity was associated with higher concentration of Na+, and lower concentrations of K+, Ca2+, Mg2+ and lower K+/Na+ ratio in flag leaf sap, ion concentrations were unaffected by sowing method.
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