Efficacy of the New Herbicide Clomazone Against Weeds in Potato (Solanum tuberosum L.), Its Effect On Quality and Its Residues in Tubers and Soil

Weeds represent a main limiting factor in potato production. In this study, the efficacy of clomazone against broadleaf and grass weeds in potato was assessed. Its effect on yield and quality and its residues in tubers and soil were also determined. Two field experiments were conducted on potato cultivar “Spunta” in winter 2020 and 2021. Treatments comprised clomazone sprayed preemergence at 1152 g a.i ha⁻¹, hand hoeing, and unweeded control. Clomazone showed an excellent performance against broadleaf and grass weeds compared to the unweeded and hoed plots. Foliar phytotoxicity symptoms were observed in the potato plants and appeared to negatively affect their growth during the two seasons. The herbicide increased the tuber yield and the sugar and starch contents compared with the untreated control, but to a lower extent than the hoeing treatment. The clomazone residues in soil and tubers were determined using HPLC-DAD. Data revealed that no detectable residues (< 0.01 mg.kg⁻¹) of clomazone were found in either tubers or the soil at harvest time. The results suggest that clomazone is a potential alternative herbicide to metribuzin for the effective control of weeds in potato and could be integrated with manual hoeing as a useful tool. However, more research is needed on the safety and efficacy of clomazone under different conditions, in different situations, and in other potato varieties.