Effects of Drought Stress on Seed Germination and Seedling Growth of Different Maize Varieties

Abstract

Maize is susceptible to drought stress, especially during germination. The experiment of seed germination and seedling growth of two maize varieties under different concentration of mannitol solution was carried out. Four mannitol concentrations were set: 0, 200, 400 and 600 mM, and the corresponding solution osmotic potential was: 0, -0.49, -0.99, and -1.49 Mpa. Results indicated that Zhengdan958 germinated more quickly and in greater numbers than Liansheng15. The germination rate, germination potential, shoot and root fresh weight, shoot and root length of two maize varieties both decreased under drought stress, but they decreased more in Liansheng15 than in Zhengdan958. However, the germination and vigor index of Zhengdan958 were obviously higher than that of Liansheng15 under the stress of 200, 400 and 600 mM mannitol. These results showed that the drought resistances of Zhengdan958 was higher than that of Liansheng15 by having more powerful root system and higher osmotic adjustment ability.