Weed Control J 2022; 21: e202200757

Research Article

Influence of straw source and amount on the selectivity of the herbicide fomesafen applied in contton pre-emergence

DOI: 10.7824/wcj.2022;21:00757

Abstract

Background

although efficient, there are still few options for selective treatments with herbicides applied in the pre-emergence of cotton, and treatments that result in injuries to the crop are often carried out.

Objective

to evaluate the influence of the amount of bean or oat straw on the selectivity of the fomesafen herbicide applied in pre-emergence of cotton.

Method

two experiments were carried out simultaneously in a greenhouse in a completely randomized design, with four replications. The experimental units were filled with sandy clay loam textured soil and the cultivar used was FMT 705. The evaluated treatments resulted from a 2 x 4 factorial arrangement, with factor A represented by two doses of fomesafen (0 and 500 g a.i. ha. ^-1 ) and factor B are four levels of straw (0, 2, 4 and 6 t ha ^-1 ). In the first experiment, common bean straw was used and in the second experiment, oat straw was used. At 30 days after emergence, the aerial part and roots of the cotton plants were collected to determine the dry mass.

Results

in general, where oat straw was used, the best results of cotton growth and less damage to the root system of the plant were observed. The bean straw reduced the dry mass of the aerial part and the root system of cotton plants.

Conclusion

this result showed that the coverage provided by the plant material also influenced the selectivity of the fomesafen herbicide.