Evaluation of maize seed treatments for Pratylenchus zeae control

Abstract

The objective of this study was to evaluate the effects of maize (Zea mays) seed treatments for the control of Pratylenchus zeae under glasshouse conditions. Seeds of the maize hybrid DKB390 treated with thiametoxam, thiametoxam + abamectin and imidacloprid + thiodicarb were used as treatments. The treated maize seeds were sown in plastic cups containing soil inoculated with 200 nematodes (juveniles and females). Two of the four experiments that were done were evaluated at 60 and 90 days after sowing (DAS). The first experiment was evaluated 30, 60 and 90 DAS, and the fourth experiment only at 90 DAS. Fresh root mass and total nematodes extracted and counted from roots of each plant were used as the assessment criteria. All seed treatments tested showed a degree of efficacy in reducing the reproduction rates of P. zeae under glasshouse conditions. The imidacloprid + thiodicarb treatment showed consistent results in all replications of all four experiments, often being the one resulting in the lowest P. zeae density. The thiametoxam + abamectin treatment was also effective in reducing nematode numbers and differed significantly from the control treatments for all four experiments. Thiametoxam used on its own as a seed treatment proved to be as effective as the mixture with abamectin in two of the four experiments and does not provide consistent results in terms of reducing P. zeae population levels.