Plant material : Seeds from the Zea mays variety
Piranão were planted in a non fertilized soil, free
from insecticides and other chemicals in an
experimental field of the "Universidade Federal de
Pernambuco ", Recife, located in a tropical area
in the northeast Brazil during the summer and
plants were sampled 7, 14 and 21 days after the
emergence. Only plants exhibiting healthy
vegetative growth were used.