For the modern maize hybrids in Brazil the increases in grain yield were contributed from enhanced density tolerance with planting density increasing from 71 ×104 plants ha-1 in the 1970s to 85 ×104 p

For the modern maize hybrids in Brazil, the increases in grain yield were contributed to by enhanced density tolerance, with planting density increasing from 7.1 ×104 plants ha-1 in the 1970s to 8.5 ×104 plants ha-1 in the 1990s.