Phytotoxicity of herbicides applied in post transplanting of seedlings of yellow passion fruit

Abstract

Brazil is the world’s leading producer of passion fruit. However, for this crop, there are no records of herbicides for weed control. Thus, the aim of this study was to evaluate the effects of herbicide application after transplanting of yellow passion fruit seedlings during growth and phytotoxicity of the crop. Twenty-one herbicides with different mechanisms of action were tested by application at 35 days after transplanting (DAT). Phytotoxicity of the crop by the herbicides was evaluated at 63 DAT, and assessments of damage to seedlings were held at 70 days DAT. No herbicide caused damage to the root system of the passion fruit plants. The herbicides glyphosate, imazapic, metsulfuron-methyl and glufosinate-ammonium reduced plant height gain. The herbicides atrazine, linuron, metribuzin, diuron, tebuthiuron and bentazon reduced leaf dry matter, stem dry matter and total dry matter of the plants. Fluazifop-p-butyl reduced height gain and leaf dry matter. Herbicides that caused the greatest damage to seedling growth also caused the greatest phytotoxicity. The herbicides oxadiazon, fenoxaprop-ethyl, tembotrione, chlorimuron-ethyl and isoxaflutole did not hinder growth and did not intoxicate the seedlings; they were the most promising for use in the total area.