The Influence of Salt-fertilizer Coupling on Corn Seed Germination and Seedling Growth

Through the indoor hydroponics and outdoor pot experiment, the effects of different concentrations of mixed salts(containing 93% Na2SO4, 5% of NaCl, 2% of NaHCO3) and different fertilizer levels coupled were explored, which have big influences for seed germination and seedling growth. The results show that: with the increasing concentration of salt, the corn's germination rate decreased, the salt injury index increased. In the same salinity level, with increasing amounts of fertilizer, salt injury index showed a trend of increased first and then decreased, when the NP total concentration was 0.036%, the salt injury index minimum. The corn seed's shoot length, root length, and number of roots decreased when the salt concentrations increased. The salt damage for roots was greater than buds. With the increased amount of fertilizer, the shoot length, root length, and root number decreased compared to the control, and the magnitudes of decrease for root was greater than bud. With the increased salinity, the plant height of corn seedlings decreased. In the 27 days of corn growth, the height was decreasing with an increasing fertilizer. When the corn growth was between 36d and 45d, the salinity was less than 0.4%. Using Nitrogen 60.75kg/ hm2, and Phosphate 186.75kg/hm2, promoted the corn growth effectively. When the salinity was more than 0.6%, using Nitrogen 60.75kg/hm2, and Phosphate 186.75kg/hm2began to significantly inhibit the growth of corn.