Influence of maize hybrids and applayed insecticides on Ostrinia nubilalis Hbn. attack

Abstract

Ostrinia nubilalis Hbn. is a corn pest that can do great damage to plants in some seasons. The aim of this paper is to study the resistance / susceptibility of hybrids to the attack of European corn borer and the effects of different doses of insecticides and time of application in protection against pests on maize plants, but primarily the influence of hybrids on attack intensity. The six maize hybrids of different maturation groups (ZP 427, ZP 434, ZP 555, ZP 600, ZP 606 and ZP 666) used for study effect of attack of Ostrinia nubillalis Hbn., on control variant T1 without application of insecticide and on variant treated with two insecticides Fobos EC (bifentrin - 200 ml ha-1) and combination of Match 050 EC and Nurelle D (lufenuron 50 g l-1 and hlorpirifos 500 g l-1 + cipermetrin 50 g l-1), 0.75 l ha-1) in two terms (in the first generation of insect flying T2 and T3 and in the second generation of insect flying T4 and T5) in three replication. The results showed the highest intensity of Ostrinia nubilalis Hbn. attack and degree of damages on control variant and significant differences between treatments for investigated parameters. Observing all hybrids and treatments, there was no statistical significance between the six examined maize hybrids of different maturity groups. In the control variant, the greatest attack (damage) was in plants, namely in the hybrid ZP 666 (94.28%) and ZP 606 (93.90%) and among the variants of applied insecticides, the greatest damage was found in the treatment T5 with the applied combination of Match + Nurelle in hybrid ZP 555 and was 92.02%. On treatment T1-control variant without insecticides, the smallest attack with Ostrinia nubilalis Hbn. was found in the hybrid ZP 434 (from 88.76%) and among the variants of applied insecticides, the smallest attack was found on variant T2 with applied Phobos in the first generation of insect in hybrid ZP 434 and amounted to 77.12%. The attack of Ostrinia nubilalis Hbn. and variation of average mass of maize cob varied in dependence of maze of hybrids and variant of insecticides application.