One of the main causes of low corn yield in Brazil is low seed quality that affects stand establishment and yield. The main goals of this research were to determine the effect of seed quality and seeding rate on corn stand establishment and yield. Four seed lots of hybrid corn BRS 201, with initial germination of 95%, 90%, 85% and 75% were sown at three seeding rates: 50, 60 and 70 thousand seeds/ha at Embrapa Milho and Sorgo, Sete Lagoas, MG, in 1996/97 and 1997/98. The parameters evaluated were: field emergence at 10 days after sowing, rate of emergence, ear number/ha, plant population/ha, ear production/ha and kernel yield/ha. Low seed vigor markedly reduced field emergence, plant vigor, number of plants, and yield. Increasing seeding rate did not overcome seed quality. There was a yield gain of 30% for seed quality improvement of 15%. Based on the results of this trial, we recommend that corn growers use seed lots with germination over 90% and seeding rate between 50 and 60.000 seeds/ha.
Zea mays; vigor; germination; emergence; seeding rate; plant population
