EFFECT OF WATER STRESS ON IMBIBITION, GERMINATION AND SEEDLING GROWTH OF MAIZE CULTIVARS

A Laboratory experiment was conducted to evaluate the effect of four level of water potential (ø) viz., 0.00, -4.09, -8.18, and -12.28 bars on the imbibitions (water absorption), germination, and seedling growth of six cultivar of maize (Zea mays L.). Mannitol was used as an osmoticum. Results showed that water stress treatments significantly (P 0.05) influenced the root-shoot length, their fresh and dry weights (except root oven dry weight) of different cultivars of maize i.e., Agaithi-72, Azam, Composite-15, Ehsan, Synthetic-551 and Yousafwala E.V. 1081. Similarly, significant variations in seedling growth were obtained among cultivars. However, interactions between water stress and cultivars for root-shoot length, and shoot fresh dry weights were also found as highly significant (P 0.01). Results also showed that increase in water stress level decreases imbibition, germination and seedling growth. Reduction in imbibition, germination and root-shoot fresh and dry weights were recorded in the highest water stress level (-12.28 bars). Results further exhibited that on the basis of total or cumulative drought tolerance index, maize cv. Azam could be ranked as drought tolerant and cv. Agaithi-72 as drought sensitive. While cultivars viz., Composite-15, Synthetic-551, Ehsan and Yousafwala E.V. 1081 were ranked as drought intermediate in response, respectively.