Chemical control of rodents and its impact on rodent infestations during subsequent cropping season

Abstract

The control of rodent pests with novel rodenticides is an important strategy subsequently they are cost-effective in reduction of agriculture damage in the urban environment. The current field study was conducted to test the efficiency of newly formulated baits of zinc phosphide (2%) and brodifacoum (0.005%) in combination and alone mixed with additives for the control of field rats prevailing wheat-groundnut cropping system of the Pothwar region, Pakistan. Burrow baiting and bait stations were employed at the early flowering stages of the respective crops, and continued through three growth stages (germination, peg formation/flowering and maturity). Treatment efficacy of the trials was assessed through counts of active rodent burrows before and after treatments at the three growth stages of these crops. The results indicated variable degrees of reduction in burrow activities following the three bait applications. The reductions in rodent activity in wheat were 88.8% at germination, 92.0% at flowering/grain formation and 95.5% at maturity stage. In groundnut, the rodent activities were reduced by 91.8%, 93.5% and 95.8% at germination, peg formation, and maturity stages, respectively. The estimated mortality at all three growth stages of both wheat and groundnut ranged between 60 and 85%. A significant impact of three rodenticides treatments on the reduction of rodent burrow density in both wheat and groundnut crops (P < 0.05) was observed. Nonetheless, comparison of the mean values reveals that the number of burrows reduced at the maturity stages (P > 0.05). The results revealed that this combination of rodenticides have more potential in enhancing bait acceptance and could be benefit to the agricultural ecosystem and may reduce the impact of secondary poisoning and environmental risks.