Crescimento de Brachiaria plantaginea e Raphanus raphanistrum em convivência com híbridos de milho submetidos a períodos de controle das plantas daninhas

The objective of this experiment was to evaluate the effects of corn hybrid cultivation and weed control periods on the population and growth of the weeds B. plantaginea and R. raphanistrum. The trial was set at Universidade Estadual the Sao Paulo (UNESP), Botucatu Campus, Sao Paulo - Brazil. A completely randomized block design with four replications was used. The treatments were arranged in a factorial scheme with four corn hybrids (C701, DINA170, XL678, and C125) and four manual weed control periods [a. 15 days after emergence (DAE); b. 15 and 30 DAE; c. 15, 30 and 45 DAE, and d. weedy]. The hybrids DINA170 and C125 significantly decreased the density of B. plantaginea. The hybrids C701, DINA170 and XL678 affected the growth of the plants, but they did not affect the emergence of new plants of R. raphanistrum. Hand-hoeing at 15 DAE decreased the dry matter weight of the weeds B. lantaginea and R. raphanistrum by 93.1%, 95.4% and 89.2%, respectively, at harvest of the four hybrids.