Effect of Seed Priming on Maize (Zea mays L.) Seed Germination and Seedling Growth under Salt Stress

Seeds of two maize(Zea mays L.) hybrid combinations of A060233×D123-42(T,a high salt-tolerant cross combination) and D168-83×A06148(S.a salt-susceptible cross combination) were primed with 80 mmol·L~(-1) NaCl.The primed seeds were subjected to salt stress of 4 NaCl concentrations(0、120、200 and 250 mmol·L~(-1)) in a sand culture experiment.The effects of the seed priming and NaCl stress on seed germination and seedling growth under salt stress were investigated.The results show that with or without priming,seed emergence rate declined.The growth of seedling was inhibited while the accumulation of dry weight reduced.Compared with unprimed seeds under the same NaCl concentration,primed seeds had higher emergence rate,higher height of seedlings and length of roots,higher leaf areas,higher dry weight of seedlings and dry weight of roots,higher salt resistance index,higher contents of chlorophyll and proline,higher ratio of K~+/Na~+in shoots and roots of seedlings.