Comparative efficacy of conventional and new rodenticides against Microtus arvalis (Pallas, 1778) in wheat and alfalfa crops

The average M. arvalis census numbers of 230/ha and 132/ha were found to cause 6.85% and 5.55% yield reduction in wheat, while the corresponding average counts of 285/ha and 253/ha caused 21.22% and 15.61% yield decrease in alfalfa crop. Twenty-eight days after treatment in wheat, the conventional rodenticides were found to reach average efficacy of 87% (bromadiolone), 95% (brodifacoum) and 82% (cholecalciferol), while the respective effectiveness in alfalfa was 81% (bromadiolone), 78% (cholecalciferol) and 95% (brodifacoum). Sodium selenite achieved 62% and 67% average efficacy in wheat and alfalfa, respectively, while cellulose reached the respective efficacies of 70% and 85%. Sodium selenite was less effective than either conventional rodenticides or cellulose. Repression M. arvalis with cellulose may significantly improve pest management programmes for rodent control in alfalfa crops.