Effect of Biostimulants and Glyphosate on Morphophysiological Parameters of <i>Zea mays</i> (L.) Seedlings under Controlled Conditions

Abstract

Maize (Zea mays L.) is the major produced crop in South Africa, but numerous abiotic/biotic stressors threaten its production. Herbicides are mainly in the agricultural sector to minimise crop yield losses caused by weed competition. However, with most weeds becoming resistant to glyphosate, South African farmers have used higher herbicide concentrations than typically recommended. This study was conducted to determine the effect of two biostimulants (brassinosteroids and KELPAK) and glyphosate on the morphophysiological parameters of maize seedlings. Experiments were carried out in the glasshouses of the Department of Soil, Crop, and Climate Sciences at the University of the Free State in Bloemfontein for eight weeks over two seasons, 2017/2018 and 2018/2019. The treatments did not significantly affect all maize morphological parameters except the plant dry mass. Compared to the control, plant dry mass was significantly (p p −1) and KELPAK (5% ai ha−1)—alone and in combination in glyphosate-resistant maize cultivars treated with glyphosate to aid maize seedlings.

Keywords

• brassinosteroids
• herbicides
• seaweed extract
• weed control