Role of genetic resources from different geographic and climatic regions in simultaneous breeding for high quality protein maize (HQPM) and stress tolerance

Abstract

Due to the low biological value of proteins of common maize, it was reinitiated breeding for high protein quality maize (HQPM) using three genetic systems, namely: opaque-2 gene, endosperm modifier genes and enhancer genes, which are increasing lysine and tryptophan content in opaque-2 background In order to alleviate effect of abiotic and biotic stress factors, the genotypes with tolerance to those factors were included. Genetic resources originating from North, Central and South America, then West, Central and Southern Africa and gene bank of Maize Research Institute 'Zemun Polje' were used. Combining breeding approaches in selection of genetic resources, field plot techniques and laboratory analysis, it was created large number of early QPM varieties, inbred lines and hybrids with modified endosperm and high yield potential under poor and good growing conditions. Created lines exhibited high combining ability in conventional and non-conventional hybrids. Yield trials showed that QPM hybrids are competing with commercial hybrids of common maize.

Zbog niske biološke vrednosti proteina zrna standardnog tipa kukuruza se pristupilo stvaranju sorata i linija kukuruza visokog kvaliteta proteina (VKP) korišćenjem tri genetička sistema: opaque-2 gena, gena modifikatora endosperma i gena enhansera koji povećavaju sadržaj lizina i triptofana u opaque-2 osnovi. Da bi se istovremeno ublažilo i delovanje abiotskih i biotskih faktora stresa uključeni su i genotipovi sa tolerantnošću na ove faktore. Korišćeni su genetički resursi poreklom iz Severne, Centralne i Južne Amerike, zatim Zapadne, Centralne i Južne Afrike i resursi iz banke gena Instituta za kukuruz 'Zemun polje'. Kombinovanjem selekcionih pristupa u izboru genetičkih resursa, tehnika u poljskim i laboratorijskim uslovima stvoren je veliki broj ranih sorata, inbred linija i hibrida VKP, modifikikovanog endosperma i visokog potencijala rodnosti pod lošim i normalnim uslovima gajenja. Takođe, stvorene inbred linije su ispoljile visoku kombinacionu sposobnost u nekonvencionalnim i konvencionalnim hibridima. Poljski ogledi su pokazali da VKP hibridi konkurišu po prinosu najboljim komercijalnim hibridima standardnog tipa kukuruza.