Inheritance of quantitative traits in diallel hybrids of sunflower

Abstract

Sunflower is one of the most important oilseed crops in the world and primary source of edible oil in many countries. The main objectives in sunflower breeding are increased seed yield and oil content in seed and thus oil yield per unit area. To achieve this goal, it is necessary to possess appropriate genetic variability, as well as information about inheritance, heterosis, heritability and relationship between seed yield and other characteristics of the plant. Six sunflower varieties were crossed using diallel method. Seed yield per plant, 1000-seed weight, oil content, plant height and head diameter were studied. Analysis included mode of inheritance, combining abilities, components of genetic variance with regression analysis, heritability and correlation between seed yield per plant and other studied traits. The inheritance of seed yield per plant exhibited superdominance, dominance of the better and poorer parent, partial dominance of the better parent and the intermediary. Additive and nonadditive components were important in the inheritance of seed yield per plant and dominant genes prevailed in relation to recessive. Heritability estimates indicated that environment had great effect on seed yield per plant. The mode of inheritance of 1000-seed weight exhibited negative superdominance, dominance of the better parent, partial dominance of poorer and better parent as well as intermediary. Analysis showed that both, additive and nonadditive, components were important in the inheritance of 1000-seed weight. The frequency of dominant genes was higher than recessive for 1000-seed weight. It was found that environmental factors had great influence on the formation of 1000-seed weight. Superdominance was prevailing as a mode of inheritance for oil content. Nonadditive component of genetic variance played a significant role in the inheritance of oil content and the presence of dominant genes was higher than recessive. Estimation of narrow sense heritability indicated that selection for high oil content can be successful. Superdominance was the most common mode of inheritance for plant height. Additive component had greater importance in the inheritance of plant height, whereas the frequency of dominant genes was higher than recessive...

Suncokret je jedna od najvažnijih uljanih biljnih vrsta u svetu i u mnogim zemljama primaran izvor jestivog ulja. Osnovni ciljevi u oplemenjivanju suncokreta jesu povećanje prinosa semena i sadržaja ulja u semenu, a preko njih i prinosa ulja po jedinici površine. Za realizacija navedenog cilja neophodno je posedovanje odgovarajuće genetičke varijabilnosti, kao i informacije o načinu nasleđivanja, heterozisu, heritabilnosti i odnosu prinosa semena sa drugim osobinama biljke. Šest sorti suncokreta ukršteno je dialelnom metodom. Ispitivane su osobine prinos semena po biljci, masa 1000 semena, sadržaj ulja, visina biljke i prečnik glave. Analizirani su način nasleđivanja, kombinacione sposobnosti, komponente genetičke varijanse sa regresionom analizom, heritabilnost i korelacija između prinosa semena po biljci i ostalih ispitivanih osobina. U nasleđivanju prinosa semena po biljci ispoljile su se superdominacija, dominacija boljeg i lošijeg roditelja, parcijalna dominacija boljeg roditelja i intermedijarnost. Aditivna i neaditivna komponenta bile su od značaja u nasleđivanju prinosa semena po biljci, a dominantni geni su preovlađivali u odnosu na recesivne. Vrednost heritabilnosti ukazala je na velik uticaj spoljašnje sredine u formiranju prinosa semena po biljci. U nasleđivanju mase 1000 semena kao načini nasleđivanja ispoljili su se negativna superdominacija, dominacija boljeg roditelja, parcijalna dominacija lošijeg i boljeg roditelja kao i intermedijarnost. Analize su pokazale da su i aditivna i neaditivna komponenta bile od značaja u nasleđivanju mase 1000 semena. Frekvencija dominantnih gena bila je veća od recesivnih za masu 1000 semena. Utvrđeno je da na formiranje mase 1000 semena velik uticaj imaju faktori spoljašnje sredine. U nasleđivanju sadržaja ulja preovlađivala je superdominacija. Neaditivna komponenta genetičke varijanse imala je značajniju ulogu u nasleđivanju sadržaja ulja, a zastupljenost dominantnih gena bila je veća od recesivnih. Heritabilnost u užem smislu ukazala je da selekcija na visok sadržaj ulja može biti uspešna. Najčešći način nasleđivanja visine biljke bila je superdominacija...