The effect of abamectin application in combination with agronomic measures on the control efficacy of cucumber root-knot nematodes and the cucumber yield

BACKGROUNDAs a registered non-fumigant nematicide, abamectin has been widely used as a soil treatment against many cash crop nematode diseases. In a previous study, we found that soil adsorption hindered the stable performance of abamectin against root-knot nematodes in the field. RESULTSIn this study, an efficient and labor-saving application method of soil blending abamectin combined with rotary tillage, a common agronomic measure, was developed to improve the efficacy of abamectin against root-knot nematode disease. We revealed the role of four parameters in this application method. At an abamectin dose of 750 g a.i. ha(-1), spray water volume of 675 L ha(-1) and rotation depth of 20 cm, abamectin was well distributed in the 0-20 cm soil layer at a concentration of 0.41-0.46 mg kg(-1), the efficacy against root-knot nematode disease was 72.12%, and the cucumber yield was 51.93 t ha(-1). At the same dosage, root irrigation and flood irrigation measures resulted in only 29.28% and 33.43% control, with cucumber yields of 42.96 and 44.73 t ha(-1), respectively. CONCLUSIONTo control root-knot nematode disease with abamectin, a soil blending application combined with rotary tilling is superior to leaching application combined with the agronomic measure of irrigation. The former application method can improve the dispersion of abamectin in the soil, enhance the efficacy of abamectin against root-knot nematodes and maintain a stable cucumber yield. In addition, the increased labor required for application combined with agronomic measures is negligible and has excellent application prospects. (c) 2023 Society of Chemical Industry.