Enhancement of salinity tolerance in wheat through soil applied calcium carbide

Calcium carbide (CaC2) has been reported to increase growth and yield of crops under normal soil conditions. This study assessed its capacity to enhance salinity tolerance in wheat (Triticum aestivum L.; cv-1076) under saline conditions. Three levels of salinity: 0, 7 and 12 dS m(-1) were created using NaCl. Nitrogen, phosphorus and potassium were applied as ammonium sulphate and KH2PO4 at 50 and 25 mg kg(-1) soil, respectively. The encapsulated calcium carbide (ECC) at 45 mg kg(-1) soil produced 1291.8 mu mols of acetylene (C2H2) and 257.5 ae mols of its product ethylene (C2H4) over a period of 80 days. The results of the pot study indicated that ECC increased the weight of spike, weight of grains per spike, length of spike, total water concentration, root/shoot ratio and relative leaf water content up to 17, 23, 22, 35, 33 and 3%, respectively, over the control. Contrary to this, salinity (at 12 dS m(-1)) decreased all these parameters up to 68, 60, 26, 30, 28 and 8%, respectively, compared to the control. These results indicate that ECC enhances salinity tolerance in wheat by improving uptake of nutrients through enhanced root growth, increased hydraulic conductivity and hormonal action of ethylene released by ECC. Total water concentration was positively correlated (0.73) with grains spike(-1) at P = 0.05.