Sunflower Breeding for Resistance to Abiotic and Biotic Stresses

Due to a specific structure of its main organs (root, stem, leaves, and head), sunflower can be successfully grown on marginal soils and in semiarid conditions, and it is more resistant to abiotic stresses, than other field crops. Unfortunately, it is very sensitive to biotic stresses

Efekat gena i kombinacione sposobnosti za visinu biljke i prečnik glave kod suncokreta

Plant height and head diameter are important parameters which effect on a yield in sunflower. Six restorer Rf lines, three tester A lines and their 18 Fl hybrids were studied, using line x tester method. Significant differences were found between restorer lines and testers and their Fl hybrids for plant height and head diameter. Regarding the inheritance of examined characteristic, super dominance and dominance of better parent occurred, and the intermediary too. Tester line HA-48A (188.25 cm) and Fl hybrid HA-48A x RHA-SELEUS (245.10 cm) had the highest mean value for plant height, and the lowest value had line RHA-BRE-1 (105.35 cm) and hybrid L-19A x RHA-BRE-1 (147.9 cm). For head diameter, the highest mean value had line L-19A (19.02 cm) and Fl hybrids HA-48A x RHA-TR-20 and L-19A x RHA-TR-20 (24.55 cm), and the lowest line RHA-BRE-1 (13.10 cm) and hybrid HA-26A x RHA-M-72 (20.25 cm). Based on the results, the following conclusion is that lines RHA-BRE-1 for plant height and RHA-SELEUS for head diameter have the best GCA, and the best SCA have hybrids L-19A x RHA-BRE-1 for plant height and HA-26A x RHA-SELEUS for head diameter. Analyzing components of genetic variance, the nonadditive component played the main role in the inheritance of plant height and the additive of head diameter. The largest average contribution in the expression of plant height had the tester A-lines (83.17%) and for head diameter Rf lines had the greatest influence (58.13%).Visina biljke i prečnik glave su značajni parametri koji utiču na visinu prinosa kod suncokreta. Metodom linija x tester ispitano je šest restorer linija, tri tester A linije i njihovih 18 F1 hibrida. Utvrđene su značajne razlike između restorer linija i testera i njihovih F1 hibrida za visinu biljke i prečnik glave. U nasleđivanju ispitivanih svojstava ispoljile su se superdominacija i dominacija boljeg roditelja, ali i intermedijarnost. Najveću srednju vrednost za visinu biljke su imali tester linija HA-48 A (188,25 cm) i Fj hibrid HA-48A x RHA-SELEUS (245,1 cm), a najmanju linija RHA-BRE-1 (105,35 cm), odnosno hibrid L-19A x RHA-BRE-1 (147,9 cm). Kod prečnika glave najveću srednju vrednost su imali tester linija L-19A (19,95 cm) i F, hibridi HA-48 A x RHA-TR-20 i L-19A x RHA-TR-20 (24,55 cm), a najmanju linija RHA-BRE-1 (13,10 cm) i hibrid HA-26A x RHA-M-72 (20,25 cm). Na osnovu dobijenih rezultata može se zaključiti da najbolje OKS imaju linije RHA-BRE-1 za visinu biljke i RHA-TR-20 za prečnik glave, a najbolje PKS, hibridi L-19A x RHA-BRE-1 za visinu biljke i HA-26A x RHA-SELEUS za prečnik glave. Analiziranjem komponenti genetske varijanse, neaditivna komponenta je imala najveći uticaj na nasleđivanje visine biljke, a aditivna na prečnika glave. Najveći prosečni doprinos u ekspresiji visine biljke dale su A-tester linije 83,17%, a za prečnik glave najveći uticaj su imale restorer linije 58,13%

Komponente varijanse i efekat gena morfoloških svojstava suncokreta (Helianthus annuus L.)

In order to enable progress in sunflower breeding, an increasing amount of attention has to be paid to the morpho-physiological traits (petiole angle and length) of this crop that have a significant effect on its seed yield and oil concentration. In the inheritance of petiole angle and petiole length the additive component of genetic variance had the predominant role in the F1 and F2 generation. The mean degree of dominance (H1/D)1/2 and the intersection of the expected regression line with the Wr axis indicated partial dominance in the inheritance of petiole angle and petiole length. Broad sense heritability for petiole angle was 88% and for petiole length 85%.Da bi se obezbedio napredak u selekciji suncokreta potrebno je obratiti veću pažnju na morfo-fiziološke osobine (ugao lisne drške i dužinu lisne drške) koje značajno utiču na prinos semena i sadržaj ulja. Radi proučavanja nasleđivanja, efekta gena, komponenti genetske varijanse i heritabilnosti ugla i dužine lisne drške šest genetski divergentnih inbred linija suncokreta u F1 i F2 generaciji primenjena analiza dialelenih ukrštanja za kombinacione sposobnosti, Griffing, 1956 metod 2, model I. Za ocenu komponenti genetske varijanse i regresionu analizu korišćen je metod MATHER and Jinks (1982). Ocena heritabilnosti u užem smislu je rađena po formuli MATHER and Jinks (1971). U nasleđivanju ugla i dužine lisne drške aditivna komponenta genetske varijanse je bila predominantna u F1 i F2 generaciji. Prosečan stepen dominacije (H1/D)1/2 i presek očekivane linije regresije sa Wr osom ukazuje na parcijalnu dominaciju u nasleđivanju ugla i dužine lisne drške. Heritabilnost u užem smislu za ugao lisne drške iznosi 88%, a za dužinu lisne drške 85%

Linija X tester analiza morfoloških svojstva i njihova međuzavisnost sa prinosom i sadržajem ulja suncokreta (Helianthus annuus L.)

One of the primary tasks of sunflower breeding is the development of inbred lines by interspecific hybridization for the purpose of obtaining high-yielding, stable hybrids that are characterized by altered plant appearance and the ability to produce a higher number of plants per unit area under intensive agriculture conditions. Studied in this paper by the line x tester method were seven new divergent cms inbred lines (A) lines, three Rf restorers utilized as testers, and 21 F1 hybrids developed. Significant differences in the mean values of all the traits studied were observed. Highly significant GCA and SCA values were obtained for petiole length (PL) and total leaf area per plant (TLA). The nonadditive component of genetic variance played the main role in the inheritance of both these traits. This was confirmed by the GCA/SCA ratios for PL and LA in the F1 generation, which were below the value of one (0.43 and 0.07, respectively). The greatest average contribution to the expression of PL (49.9%) and TLA (57.1%) was found in the female A lines. A positive correlation was found between seed yield (SY) and PL (0.374*) and TLA (0.630**), while seed oil content (SOC) and TLA were found to be negatively correlated (-0.520**). The findings of this study can be used in the development of new high-yielding sunflower hybrids with high yields based on interspecific hybridization.Jedan od primarnih zadataka oplemenjivanja suncokreta je stvaranje inbred linija putem interspecijes hibridizacije radi dobijanja visokoprinosnih i stabilnih hibrida promenjenog izgleda koji u uslovima intenzivne agrotehnike omogućavaju povećanje broja biljaka po jedinici površine. Za linija x tester analizu korišćeno je sedam novih divergentnih (A) citoplazmatski muško sterilnih inbred linija nastalih interspecijes hibridizacijom, tri Rf-restorer linije kao testeri i 21 hibrid F1 generacije. Dobijene su značajne razlike u srednjim vrednostima za sva ispitivana svojstva. Izračunate su visoko značajne vrednosti OKS i PKS za dužinu lisne drške (DLD) i ukupne lisne površine po biljci (ULP). Glavnu ulogu u nasleđivanju oba svojstva ima neaditivna komponenta genetske varijanse. To potvrđuje i odnos OKS/PKS u F1 generaciji koji je manji od jedinice i iznosi 0.43 za DLD i 0.07 za ULP. Najveći prosečan doprinos u ekspresiji ovih svojstava imale su A-linije majke i to (49.9%) za DLD i (57.1%) za ULP. Ustanovljena je pozitivna međuzavisnost prinosa semena (PS) sa DLD (0.374*) i ULP (0.630**). Između sadržaja ulja u semenu (SU) i ULP ustanovljena je značajna negativna međuzavisnost (-0.520**). Ova istraživanja mogu biti od značaja za stvaranje novih visoko prinosnih genotipova suncokreta na bazi interspecies hibridizacije

Efekat heterozisa za prinos semena i komponente prinosa suncokreta

The development of new high-yielding and stable sunflower hybrids based on interspecific hybridization requires information on the heterotic effects for agronomically important traits in the F, generation. Heterotic effects for seed yield, plant height and head diameter were studied in interspecific sunflower hybrids developed by the line x tester method. The female inbred lines were developed by interspecific hybridization, while the male restorer inbreds with good combining abilities were used as testers in the form of fertility restorers. F, hybrids were obtained by crossing each tester with each female inbred. The inbred lines and their F, hybrids differed significantly in their mean values of the traits under study. Heterosis values for seed yield per plant were positive and highly significant relative to both the parental mean (98.4-274.1%) and the better parent (54.8-223.2%). Significantly less heterosis was recorded in the case of plant height relative to parental mean (19.0-66.0%) and better parent (-3.9-51.6%). With head diameter, the heterotic effect ranged from 19.0 to 55.6% (parental mean) and from 7.8 to 36.6% (better parent). The results of this study may be used for the development of new high-yielding and stable sunflower hybrids based on interspecific hybridization.Stvaranje visoko prinosnih i stabilnih hibrida suncokreta na bazi interspecijes hibridizacije zahteva posedovanje informacije o efektu heterozisa za agronomski važna svojstva u F, generaciji. Efekat heterozisa za prinos semena. visinu biljke i prečnik glave proučavan je kod interspecijes hibrida nastalih ukrštanjem primenom linija x tester metoda. Inbred linije majke nastale su interspecijes hibridizacijom, a restorer inbred linije oca dobrih kombinacionih sposobnosti korišćene su kao testeri u formi restauratora fertilnosti. Hibridi F1 generacije nastali su ukrštanjem svakog testera sa svakom inbred linijom majke. Vrednosti heterozisa za prinos semena po biljci bile su pozitivne i visoko značajne u odnosu na roditeljski prosek (98.4-274.1%) i u odnosu na boljeg roditelja (54.8-223.2%). Znatno niži efekat heterozisa ustanovljen je za visinu biljke (19.0-66.0%) u odnosu na roditeljski prosek i u odnosu na boljeg roditelja (6.1-51.6%). Kod prečnika glave vrednosti heterozisa su se kretale od 19.0% do 74.7% u odnosu na roditeljski prosek i od 11.6-36.6% u odnosu na boljeg roditelja

Komponente fenotipske varijabilnosti za prečnik glave suncokreta

Sunflower is the main crop species for the production of edible oil in many countries of the world, including ours. Plant height and head size, form and position on the stem as well as the number of leaves, their size, duration and distribution on the plant all play an important role in defining optimal plant architecture in sunflower hybrids (Škorić, 1975, 1989, 2002). In order to monitor the mode of inheritance and gene effects for head diameter in the F1 and F2 generations, half diallel crosses were made in six genetically divergent sunflower inbreds. The mean values of the trait in question differed significantly. The mode of inheritance of head diameter in the F1 generation was superdominance in all but four crosses, which had dominance instead. In the F2 generation, on the other hand, the prevailing mode was dominance, while superdominance was recorded in four cases. The dominant component accounted for the bulk of genetic variance, and the mode of inheritance of head diameter taking into account both the F1 and F2 generations was superdominance. These findings may prove valuable for developing high-yielding sunflower genotypes.Suncokret je u mnogim zemljama u svetu i kod nas osnovna biljka za proizvodnju jestivog ulja. Visina biljke, veličina, forma i položaj glave na stablu, broj listova, njihova veličina, trajanje i raspored na biljci imaju važnu ulogu u definisanju optimalne arhitekture hibrida suncokreta (Škorić 1975; 1989; 2002). U cilju praćenja načina nasleđivanja i efekta gena prečnika glave suncokreta u F1 i F2 generaciji izvršena su dialelna ukrštanja isključujući recipročna sa šest genetski divergentnim inbred linijama suncokreta. Dobijene su značajne razlike u srednjim vrednostima za ispitivano svojstvo. Prečnik glave se u F1 generaciji nasleđivao superdominantno jedino se u četiri ukrštanja javila dominacija, dok se u F2 generaciji nasleđivao dominantno, a superdominacija se zadržala u četiri kombinacije. Glavni deo genetske varijanse čini dominantna komponenta, a način nasleđivanja prečnika glave je superdominacija uzevši u obzir sve kombinacije ukrštanja u obe generacije (F1 i F2). Ova istraživanja mogu biti od značaja u stvaranju visoko prinosnih genotipova suncokreta

Genetska varijansa komponenti prinosa suncokreta - Heliantus annuus L.

The main goals of sunflower breeding in Yugoslavia and abroad are increased seed yield and oil content per unit area and increased resistance to diseases, insects and stress conditions via an optimization of plant architecture. In order to determine the mode of inheritance, gene effects and correlations of total leaf number per plant, total leaf area and plant height, six genetically divergent inbred lines of sunflower were subjected to half diallel crosses. Significant differences in mean values of all the traits were found in the F1 and F2 generations. Additive gene effects were more important in the inheritance of total leaf number per plant and plant height, while in the case of total leaf area per plant the nonadditive ones were more important looking at all the combinations in the F1 and F2 generations. The average degree of dominance (Hi/D)1/2 was lower than one for total leaf number per plant and plant height, so the mode of inheritance was partial dominance, while with total leaf area the value was higher than one, indicating super dominance as the mode of inheritance. Significant positive correlation was found: between total leaf area per plant and total leaf number per plant (0.285*) and plant height (0.278*). The results of the study are of importance for further sunflower breeding work.Oplemenjivanje suncokreta u svetu i kod nas usmereno je na povećanje prinosa semena i sadržaja ulja po jedinici površine, otpornosti prema bolestima insektima i stresnim. uslovima optimalizacijom arhitekture biljke. U cilju utvrđivanja načina nasleđivanja, efekta gena i međuzavisnosti ukupnog broja listova po biljci, ukupne lisne površine po biljci i visine biljke, izvršena su dialelna ukrštanja isključujući recipročna sa šest genetski divergentnih inbred linija suncokreta. Dobijene su signifikantne razlike u srednjim vrednostima za sva ispitivana svojstva F1 i F2 generaciji. Aditivni efekat gena je bio od većeg značaja u nasleđivanju ukupnog broja listova po biljci i visini biljke dok je neaditivni efekat gena bio značajniji kod ukupne lisne površine po biljci uzevši u obzir sve kombinacije ukrštanja u F1 i F2 generaciji. Prosečan stepen dominacije (H1/D)1/2 je kod ukupnog broja listova po biljci i visine biljke manji od jedinice iz toga se može zaključiti da je način nasleđivanja parcijalna dominacija, a kod ukupne lisne površine je veći od jedinice što ukazuje na superdominaciju. Značajna pozitivna međuzavisnost ustanovljena je između ukupne lisne površine po biljci i ukupnog broja listova po biljci (0.285*), visine biljke (0.278*). Rezultati ovih istraživanja imaće značaja u daljem radu na oplemenjivanju suncokreta