POVEZANOST ISHRANE KUKURUZNOGA MOLJCA SA SADRŽAJEM DUŠIKA U LISTU U SKLOPU RAZLIČITE POLJOPRIVREDNE PRAKSE

One of the most destructive maize pest in Croatia is European corn borer (Ostrinia nubilalis Hübner) (ECB). The aim of this study was to determine the influence of irrigation, nitrogen fertilization, different maize genotypes and nitrogen leaf content on ECB feeding activity. The experiment was set up in Osijek, Croatia under field conditions during 2012-2013 vegetation season. Experiment treatments were as follows: three irrigation levels (A1 - control, A2 from 60% to 80% field water capacity - FWC and A3 from 80% to100% FWC), three nitrogen fertilizer levels (B1 - 0, B2 - 100 and B3 - 200 kg N/ha) and four different genotypes (C1 - OSSK 596; C2 - OSSK 617; C3 - OSSK 602 and C4 - OSSK 552). Ear weight, number of larvae in stem and shank, tunnel length and nitrogen leaf content were evaluated. Genotype C1 was the most susceptible for following the tested variables of ECB feeding: tunnel length (TL), larvae in stalk (LS) and total number of larvae (TNL) at P<0.05 probability level. By raising the level of irrigation, European corn borer feeding activity was reduced while by raising the level of nitrogen fertilization feeding activity was increased. These results suggest that good production practices can significantly affect the susceptibility of maize to European corn borer.Jedan od najznačajnijih štetnika na kukuruzu je kukuruzni moljac (Ostrinia nubilalis Hübner) (ECB). Cilj ovog istraživanja bio je utvrditi utjecaj navodnjavanja, dušične gnojidbe, različitih genotipova i sadržaja dušika u listu kukuruza na ishranu kukuruznog moljca. Pokus je postavljen u Osijeku, Hrvatska, u poljskim uvjetima, tijekom vegetacijske sezone 2012.-2013. Tretmani pokusa su sljedeći: tri razine navodnjavanja (A1 – kontrola, A2 – 60%-80% poljskoga vodnoga kapaciteta-PVK i A3 - 80%-100% PVK), tri razine dušične gnojidbe (B1 – 0 kg N/ha, B2 - 100 kg N/ha i B3 - 200 kg N/ha) i četiri genotipa (C1 - OSSK 596; C2 - OSSK 617; C3 - OSSK 602 i C4 - OSSK 552). Ocjenjivana svojstva bila su: masa klipa, broj ličinki u stabljici i dršci klipa, dužina oštećenja te sadržaj dušika u listu kukuruza. Genotip C1 bio je najosjetljiviji za ispitivane varijable: dužinu oštećenja (TL), broj ličinki u stabljici (LS) i ukupan broj ličinki po biljci (TNL), na razini značajnosti P