Influence of Soil Works on the Damage by the Western Corn Rootworm ( Diabrotica Virgifera Virgifera Leconte ) in Grain Maize in the Banat’s Plain

Because of the damage caused currently by the Western corn rootworm (Diabrotica virgifera virgifera LeConte) we need to pay particular attention to all its control methods. In this respect, soil works, together with crop rotation, play an important role. In the field, the mean values of damage on maize roots on different lands differentiated from the point of view of soil works had a lower span (0.06). Ploughing caused a span of 0.51 associated with a mean variability(15.47%), i.e. a significantly higher attack in 2010 than in 2011 and 2012. The damage on the grubbered lands showedvalues ranging between 1.69 in 2011 and 2.13 in 2010, with a span of 0.44 and a variability of 14.36%. In disked land,there were damage values between 1.67 in 2011 and 2.09 in 2010 on the background of lower variability (11.96%)than on previous lands. In the field, under an isolator, there were no significant differences in maize root damage. Thus, on the land ploughed, in the conditions of 2012, the attack was 15-27% significantly lower than in 2011 and 2010. In the disked variant, maize root damage reached a span of 0.97, inferior to the other two lands, with limits between 1.67 in 2012 and 2.64 in 2010. The level of the attack on the grubbered land had a span of 1.13, with limits between 1.63 in 2012 and 2.76 in 2010.