In vitro and micro-plot predatory activity of the mite Caloglyphus mycophagus against populations of nematode larvae of agricultural importance

The present study evaluated the in vitro and micro-plot predatory activity of the mite Caloglyphus mycophagus against Haemonchus contortus (L₃) and Nacobbus aberrans (J₂). To determine the in vitro predation of the mite, four groups were formed in Petri dishes: (1) 5,000-H. contortus, (2) 1,000-N. aberrans (3) 5,000-H. contortus and 5 mites and (4) 1,000-N. aberrans and 5 mites. The plates were kept for 15 days at 28 °C. For the evaluation of micro-plots with mites against nematodes, Italian ryegrass was used, and additionally, micro-plots with faeces-ivermectin/nematodes/mites were used over 15, 30 and 45 days. At each time, two control groups were formed containing 5,000 larvae of H. contortus and 1,000 s-stage juveniles of N. aberrans, respectively, and two treated groups containing the same amounts of nematodes as the controls and 5 mites on each micro-plot. The results showed an in vitro reduction of 72.86% for N. aberrans and 42.17% for H. contortus. For the micro-plot experiment at 45 days, the percentage of reduction was 78.95 and 63.16% for H. contortus and N. aberrans, respectively. In the case of the micro-plots with ivermectin, mite mortality was 100%. The mite C. mycophagus showed activity in vitro and in the micro-plot against H. contortus and N. aberrans. In addition, we provide evidence that ivermectin in cattle faeces leads to a 100% mortality for C. mycophagus in micro-plots.