The main objective underlying sunflower breeding programs is to develop high-yielding productive F 1 hybrid cultivars. This study was conducted to investigate the genetic control of some agro-morphological traits of new sunflower F 1 hybrids. For this purpose, fourteen inbred lines of sunflower were crossed with three male sterile inbred lines. Their hybrids (14 hybrids) were then evaluated against three control cultivars. The data thus obtained were analyzed using the nested model (North Carolina Design І) as a completely randomized block design (CRBD) with four replications. Analysis of variance showed that the hybrids were significantly different in all the traits studied, except for head and stem diameters. From among the hybrids evaluated, Cms19 × Rn1-81 was found to have the highest seed yield and oil content. Cluster analysis classified the hybrids into four different groups. Genetic analysis showed that days to maturity, seed weight, and oil content (%) were under the additive gene action. Breeding strategies based on selection could be suggested for the improvement of these traits. Head angle, head diameter, seed yield, and oil yield were under the dominance gene action; breeding based on hybridization methods is, therefore, proposed for these traits. Finally, both additive and dominance gene actions were observed to play important roles in the genetic control of plant height and stem diameter.Key words: additive, dominance effect, evaluation of hybrids, oil content, sunflower, yield
IZVLEČEK
GENETSKA ANALIZA AGRO-MORFOLOŠKIH LASTNOSTI PRI OBETAJOČIH KRIŽANCIH NAVADNE SONČNICE (Helianthus annuus L.)Glavni cilj žlahniteljskih programov navadne sončnice je razvoj visoko produktivnih F 1 hibridnih sort. V raziskavi smo preučevali genetsko kontrolo nekaterih agro-morfoloških lastnosti nekaterih novih F 1 hibridov navadne sončnice. V ta namen smo opravili križanja 14 inbridiranih linij navadne sončnice s tremi moško sterilnimi inbridiranimi linijami. Dobljeni križanci (14 hibridov) so bili ovrednoteni glede na tri kontrolne sorte. Tako pridobljeni podatki so bili analizirani z vgnezdenim modelom (North Carolina Design І) v bločni zasnovi s štirimi ponovitvami. Analiza variance je pokazala, da so bili križanci značilno različni v vseh preučevanih lastnostih, z izjemo premera koška in premera stebla. Izmed ovrednotenih križancev je imel križanec Cms19 × Rn1-81 največji pridelek semena in največjo vsebnost olja. Klastrska analiza je razvrstila križance v štiri skupine. Genetska analiza je pokazala, da so bile lastnosti, kot so število dni do zrelosti, masa semena in vsebnost olja (%), pod aditivno gensko kontrolo. Za izboljšanje teh lastnosti priporočamo žlahniteljsko strategijo zasnovano na selekciji. Lastnosti kot so naklon koška, premer koška, pridelek semena in pridelek olja so bile dominantno dedovane, zato za te lastnosti priporočamo žlahtnenje na osnovi križanja. Pri lastnostih kot sta višina stebla in njegov primer smo opazili pomembni vlogi tako aditivnega kot dominantnega delovanja genov.Ključ...
