Manejo da fitotoxicidade de herbicidas pós - emergentes na cultura do milho ( Zea mays L.)

Abstract

This work aimed to evaluate whether the use of herbicides such as glyphosate and atrazin, alone or in mixture, can cause damage to the crop, in addition to combinations with foliar fertilizers to reduce these damages. Thus, a completely randomized design (CRD) was used, with 10 treatments and 4 repetitions. All applications were carried out using a back sprayer when the plant had 4 permanent leaves and following the dosages indicated for each of the products. With the exception of stem diameter, all other parameters analyzed showed statistical differences (plant height, green matter weight, ear insertion height, ear weight, weight of a thousand grains and yield), with T1 (without weeding) , T5 (glyphosate), T2 (without weeding + foliar), T6 (glyphosate + foliar), T3 (without weeding + foliar), T10 (glyphosate + atrazin + foliar) and T9 (glyphosate + atrazin) the treatments with the worst averages obtained, as an example productivity: T1 (2.72 kg/6.3 m2); T5 (2.89 kg/6.3 m2); T2 (3.04 kg/6.3 m2); T6 (3.08 kg/6.3 m2); T3 (3.42 kg/6.3 m2); T10 (3.49 kg/6.3 m2); T9 (3.69 kg/6.3 m2) and T4 (weeding + foliar), T7 (atrazin) and T8 (atrazin + foliar) the treatments with the best averages: T4 (4.09 kg/6.3 m2); T7 (3.84 kg/6.3 m2); T8 (3.79 kg/6.3 m2), indicating that atrazin was more efficient in controlling weeds, less phytotoxic and that the foliar was efficient in reducing these injuries when combined with the treatment.