Genetička osnova nasleđivanja visine biljke kukuruza

The aim of this study, on the grounds of direct and reciprocal diallel crossing of five inbred lines of maize, was to determine: variability, heterosis, combining ability and genetic basis of plant height inheritance. The experiment was based on the principle of randomized block design in four repetitions during two years. Analysis of variance of combining abilities for plant height indicates the significance of general and specific combining abilities. The GCA/SCA ratio shows that for the inheritance of these traits non-additive genes are the most important. Variations between direct and reciprocal crossing of this trait were highly significant in all combinations except in combination of ZPL-11/6 x NS-1445, with the largest effect of reciprocity established in combination of ZPL-11/6 x BL-47 in both years. This indicates that regarding the inheritance of plant height, apart from nuclear genes, plasma genes are involved as well. Eight out of ten hybrid combinations had highly significant positive values of SCA. The high value of SCA for this trait was noticed in the case of a hybrid combination of F-7R and lines that were generally bad combiners (ZPL-11/6 and BL-47; hybrid combinations where one parent was with high GCA and the other with low GCA), which was probably due to interactions between parents' genes.Cilj ovog istraživanja je bio da se na osnovu direktnog i recipročnog dialelnog ukrštanja pet inbred linija kukuruza utvrde: varijabilnost, heterozis, kombinacione sposobnosti i genetička osnova nasleđivanja visine biljke. Ogled je postavljen po metodu slučajnog blok sistema u četiri ponavljanja u toku dve godine. Analiza varijanse kombinacionih sposobnosti za visinu biljke ukazuje na značajnost i opštih i posebnih kombinacionih sposobnosti. Odnos OKS/PKS pokazuje da u nasleđivanju ove osobine značajniju ulogu imaju neaditivni geni. Razlike između direktnog i recipročnog ukrštanja za ovu osobinu bile su visoko značajne kod svih kombinacija, osim kombinacije ZPL-11/6 x NS-1445, a najveći efekat reciprociteta ustanovljen je kod kombinacije ZPL-11/6 x BL-47 u obe godine ispitivanja. Ovo nam ukazuje da u nasleđivanju visine biljke, osim nuklearnih učestvuju i plazma geni. Visoko značajne pozitivne vrednosti PKS imalo je osam od ukupno deset hibridnih kombinacija. Visoke vrednosti PKS za ovu osobinu imale su hibridne kombinacije F-7R i linije koje su bile loši opšti kombinatori (ZPL-11/6 i BL-47; hibridne kombinacije gde je jedan roditelji sa visokom OKS, a drugi sa niskom OKS), što je verovatno posledica interakcije između gena roditelja