| Přispěvatelé: |
Živanović, Tomislav, Dodig, Dejan, Prodanović, Slaven, Branković, Gordana, Kandić, Vesna |
| Popis: |
Istraživanje biljaka u ranim fazama porasta postalo je uobičajena praksa jer ima potencijal da se na brži i lakši način identifikuju genotipovi sa poželjnim osobinama korena i stabla, kao i sa boljom tolerantošću na stres. Pokazano je da brži rani porast kod biljke pšenice doprinosi većoj sezonskoj iskoristljivosti vode, što utiče na povećanje ukupne biomase, i na kraju na povećanje prinosa zrna. Cilj ovog istraživanja je bio da se izvrši ocena 101 genotipa hlebne pšenice na osnovu osobina korena i stabla klijanaca u hidroponskoj kulturi u kontrolisanim uslovima fitotrona, kako bi se izdvojili oni sa bržim ranim porastom korena i stabla kao preduslov za kasniju veću tolerantnost na stres. Odabrani genotipovi su zatim međusobno ukrštani i zajedno sa F1 potomstvom testirani na otpornost na veštački izazvan osmotski stres. Rezultati ispitivanja u fazi klijanaca su verifikovani u realnijim uslovima sredine, u zemljišnom supstratu u stakleniku, u fazi bokorenja. Varijabilnost osobina korena u fazi klijanaca bila je veća u odnosu osobine stabla. Ispitivani genotipovi su se najviše razlikovali u osobinama koje opisuju arhitekturu korenovog sistema – grananje, ugao i broj bočnih korenova. Genotipovi iz Srbije pokazali su niske vrednosti dužine i težine korena i stabla, ali visoke vrednosti osobina arhitekture korenovog sistema. F1 potomstvo je imalo duži primarni koren i širi ugao rasta seminalnih korenova u odnosu na roditelje. Takođe, F1 potomstvo bilo je otpornije na osmotski stres u odnosu na roditelje. U fazi bokorenja kod većeg dela nove germplazme došlo je do povećane preraspodele suve materije u koren u odnosu na stablo. Dve kombinacije ukrštanja koje su se u ovom istraživanju izdvojile kao superiorne u pogledu nadzemnih osobina i osobina korena su Euklid x CHI-4 i WWBMC2 x Ingenio. Iz ovih kombinacija bi se u daljem procesu selekcije moglo očekivati izdvajanje boljih linija od roditeljskih u pogledu ranog porasta, kako u povoljnim tako i u stresnim uslovima sredine. Veliko slaganje rezultata u fazi klijanaca i fazi bokorenja može pružiti prednost oplemenjivačima, s’obzirom da je selekcija u fazi klijanaca lakša, jeftinija i manje zahtevna od selekcije biljaka u kasnijim fazama razvoja na polju. Research of plants in the early stages of growth has become a common practice because it makes it possible to identify genotypes with desired root and shoot traits and better tolerance to stress in a faster and easier way. It was shown that faster early growth of wheat plants contributes to higher seasonal usability of water which affects the increase of total biomass and eventualy the grain yield. The aim of this research was to evaluate 101 genotypes of bread wheat based on root and shoot traits of seedlings in hydroponic culture under controlled phytotron conditions, in order to select those with higher early root and shoot growth as a precondition for later higher tolerance to stress. The selected genotypes were then interbred and together with F1 progeny tested for resistance to artificially induced osmotic stress. Research results in the seedling stage were verified in the more realistic environmental conditions, in the greenhouse soil substrate, in the booting phase. Variability of root traits in the seedling phase was higher compared to that of shoot traits. The examined genotypes differed mostly in those properties which describe the architecture of the root system – branching, angle and number of seminal roots. Genotypes from Serbia showed low values regarding length and weight of root and shoot, but the values regarding the architecture of the root system were high. F1 progeny had longer primary roots and wider growth angles of seminal roots compared to parents. Also, F1 progeny had higher tolerance to osmotic stress compared to parents. In the booting phase most of the new germplasm had increased redistribution of dry matter into the root compared to the shoot. Two crossbreeding combinations in this research that stood out as superior with regard to aboveground and root properties are Euklid x CHI-4 and WWBMC2 x Ingenio. In terms of early growth in favourable as well as in stressful environmental conditions better lines than parental ones could be expected to stand out in the process of further selection from these combinations. High correlation between results in the seedling phase and the booting phase can give advantage to breeders, as selection in the seedling phase is easier, cheaper and less demanding than the selection of plants in the later development phase in the field. |
