Influence of moisture stress and growth substances on germination and seedling growth of wheat (Triticum aestivum L.)

With the objective of mitigating adverse effects of moisture stress on germination and seedling growth of wheat, four growth substances viz. ethephon, paclobutrazol, succinic acid, triademifon with varying concentrations and distilled water were used as seed treatment in a lab experiment. Moisture stress of -0.4 MPa induced with the application of mannitol significantly reduced speed of germination and suppressed root, shoot and coleoptile elongation. However, due to less adverse effect of water stress on root growth, root-shoot ratio was increased. Thus, decline in speed of germination, root elongation, shoot growth and coleoptiles length was 51, 5.70, 58 and 2.85 percent, respectively. Eventually, maximum speed of germination (23.98), root length (10.00 cm), shoots length (24.57 cm) and coleoptiles (5.09 cm) were found in case of control; whereas values of these parameters were minimum under moisture stress with no treatment. Pre-sowing seed treatment in ethephon, paclobutrazol, succinic acid, Triademifon and distilled water considerably accelerated speed of germination. Different concentrations of growth substances exhibited varied effect on these parameters. Seedling growth was further checked by the application of growth substances but seedlings were healthier than the untreated ones. Ethephon application @ 400 mg l-1 under moisture stress had more pronounced and ameliorating effect on speed of germination.