Integrated weed control: combination of white cabbage (Brassica oleracea L.) with reduced herbicide doses on redroot pigweed (Amaranthus retroflexus L.) and maize

The aim of the study was to minimize environmental impacts by reducing the amount of herbicides and at the same time to positively affect plant health. In this study, a combination of white cabbage (Brassica oleracea L.) extract known to have allelopathic effect with reduced doses of Foramsulfuron + Iodosulfuron Methyl-Sodium + Isoxadifen-Ethyl (Safener) was investigated against maize (Zea mays L.) and redroot pigweed (Amaranthus retroflexus L.). The study was conducted at the Department of Plant Protection, Van Yüzüncü Yıl University, from 2019 to 2020. In the study, the aqueous extract of white cabbage (15, 30, 45 and 60%), the licensed dose (2000ml/ha of herbicide with active ingredient Foramsulfuron + Iodosulfuron Methyl-Sodium + Isoxadifen-Ethyl (Safener) and reduced doses of this herbicide were used as 100, 50 and 250 ml/ha. In addition, reduced doses were administered with cabbage extracts. According to the results, no phytotoxic effect of applications was observed in maize. In addition, it was determined that there was no statistical difference between the all treatments and control groups. On the other hand, when the dry weight values of redroot pigweed were evaluated statistically, 60% concentration of white cabbage extract was in the same group with 1/4 and 1/8 reduced doses of Foramsulfuron + Iodosulfuron Methyl-Sodium + Isoxadifen-Ethyl (Safener). In addition, the combination of all extract concentrations and reduced herbicide doses was in the same group with 0.03 g dry weight value in 1/2 reduced herbicide application. In conclusion, the use of white cabbage extract, both alone and in combination with reduced herbicide doses, demonstrated potential as an alternative weed management strategy, effectively suppressing redroot pigweed without causing phytotoxic effects on maize. It is thought that the results obtained will provide a more sustainable and environmentally friendly weed control strategy in agricultural production by offering advantages such as reducing the cost of herbicide use, slowing the development of resistance and increasing food safety by reducing the risk of chemical residues.