Competition between weeds and crops results in a lower availability of some resources to crop species, which causes
deficiencies, such as water and nutritional deficiencies and low light quality or quantity. The aims of this study were to
evaluate the effects of
Urochloa brizantha
(Hochst. ex A. Rich.) R.D. Webster, cv. Xaraés (brachiaria) emergence times
comparing with corn (
Zea mays
L.), in addition to the fertilization and application of different nicosulfuron and atrazine
herbicides levels, on the physiological characteristics of intercropped species. The physiological characteristics
Brachiaria
plants that were treated with herbicides were negatively affected. The emergence time of
Brachiaria plants in comparison
with corn altered the physiological characteristics of both. The
Brachiaria plants that emerged before corn presented higher
photosynthetic and transpiration rates and reduced the intensity of these characteristics in corn. Thus, the
Brachiaria plants
that emerged before the corn crop presented a higher physiological efficiency, and they were more competitive than the
weeds that emerged during other seasons.
