Research on the attack produced by Ostrinia nubilalis HBN. larvae at different genotypes of maize in the conditions of Central Moldova

Abstract

During the maize vegetation period, Ostrinia nubilalis larvae causes production losses by producing attack on the stem, cob or inflorescence. To reduce losses, are chosen maize hybrids that are tolerant to larval attack. But the attack depends on the climatic conditions at the time of eggs laying and the appearance of larvae, the phenophase in which the crop is infested and the numerical pressure of the population in that region. This paper presents the results obtained from the observations and determinations made on the attack produced by the larvae of Ostrinia nubilalis Hbn. to several romanian and foreign maize genotypes, in the conditions of Central Moldova. The average frequency of attack produced by the Ostrinia nubilalis Hbn. larvae were 29.76%, the minimum value of the attack being 17.50% and the maximum reached to 47.67%. Among the genotypes studied, Deliciul verii recorded very significant values of all monitoring parameters, the frequency of attack was 47.67%, the most numerous holes (2.63) and galleries (2.14) were identified, and the larvae created galleries with an average length of 22.46 cm. An average, 0.73 holes/plant were register, the larvae created 0.65 galleries/plant with a length of 8.38 cm and were identified 0.38 larvae/plant.