Breeding for improved biomass yield in triticale

Mohamed, Mohammed Naweed (2020-04)

Thesis (MScAgric)--Stellenbosch University, 2020.

Thesis

ENGLISH ABSTRACT: Triticale (x Triticosecale Wittmack ex. A. Camus, AABBRR, 2n=6x=42) is the first manmade wheat developed through distant hybridization between rye [Secale cereale, RR, 2n=2x=14] and bread wheat (Triticum aestivum, AABBDD, 2n=6x=42). Triticale combines the qualities of its parents such as high degree of pest and disease resistance and potential to produce high yield gains when cultivated under drought and acid soil conditions. These and other characteristics sparked the attention paid to the crop. Triticale is being largely studied for its dual functionality, which includes its ability to serve as a grazing crop by producing biomass yields which are highly competitive with other forages and its ability to be used for grain production. Believed to be rich in fibre, producing large quantities of biomass material and requiring reduced amounts of management, this crop has the potential to be regarded as a high potential alternative to be included into crop rotations to supplement feedstocks. A multilocation research study was conducted over two years of which selected triticale entries were evaluated with a selection of barley, oats and rye crops as well as evaluated against advanced breeding triticale entries. A two-stage biomass sampling approach was utilised, sampling at 30 cm plant height (GS29-31) or milk stage and during the soft dough growth stage (GS69-71). Statistical analyses were conducted via Agrobase software, in which a General linear model approach was done with a randomised complete block design. A Nearest Neighbour Analysis (NNA) was conducted as well for increased accuracy. Triticale entries that were ranked among the best producers in terms of biomass yield during 2016 were included in 2017, whilst entries that were ranked the best during 2017 were further evaluated. Triticale on average produced a 1 000 kg ha-1 of biomass yield during the first cutting, indicative of its potential to offer grazing material and being superior to its other competitors in most cases. Within the soft dough stage biomass yields exceeded 12 000 kg ha-1. Heritability was measured among the trials for the trait of dry matter yield, with heritability values ranging from 0.14 to 0.88 across the trials during soft dough. The CV reported for the trials ranged from 7.95% to 24.8%. Among the top performing entries in terms of biomass yield at the end of the second year of the study, five oats, one barley and eight triticale entries were selected and analysed for nutritional value. The nutritional parameters analysed included ash, crude protein, fibre, fat, moisture and dry matter content. Certain triticale entries were among the top ranked entries in terms of both biomass yield as well as nutritional value. Through this study the hypothesis which considered triticale having high potential for consideration as an alternative crop to be included on rotations, is accepted. The entries "AgBeacon", "Snel", "US2017", "US2018" and "17USTRITEL020" have been selected potential crossing parents to be included into a formal breeding programme aimed at improving biomass yield. The need for further research to be conducted for further improvement of triticale is clear from this study. Further research aimed at increasing biomass yield of triticale as well as nutritional value will aid a greater uptake and utilization of the crop in the industry.

AFRIKAANSE OPSOMMING: Korog (x Triticosecale Wittmack ex. A. Camus, AABBRR, 2n = 6x = 42) was die eerste mensgemaakte kleingraan wat ontwikkel is deur middel van verbastering tussen rog (Secale cereale, RR, 2n = 2x = 14) en broodkoring (Triticum aestivum, AABBDD, 2n = 6x = 42). Korog is die kombinasie van sy ouers se eienskappe wat in hoe mate van plaag- en siektebestandheid het asook die potensiaal om hoë opbrengste te gee wanneer verbou word onder droogte en suur grondtoestande. Korog word grotendeels bestudeer vir sy dubbele funksionaliteit omdat dit vir graanproduksie gebruik kan word asook as 'n weidingsgewas kan dien, deurdat dit biomassa-opbrengste produseer wat die gewas baie meer mededingend maak in vergelyking met ander gewasse. Korog is ryk aan vesel en kan groot hoeveelhede biomassa produseer. Die gewas benodig 'n beperkte hoeveelheid aandag en het hoe potensiaal om as 'n alternatiewe gewas ingesluit te word in wisselbou. 'n Multi-lokateit navorsingstudie was oor twee jaar uitgevoer, waartydens geselekteerde korogkultivars vergelyk was met 'n seleksie van gars, hawer, rog en gevorderde korogteelmateriaal. Monsterneming was gedoen in twee groeifases waartyends die planthoogte 30 cm (GS29-31) was en in die sagte deeg/melkstadium (GS69-71). Statistiese ontledings was uitgevoer via Agrobase-sagteware, waarin 'n algemene liniere modelbenadering toegepas was op 'n ewekansige volledige blokontwerp. 'n "Nearest Neighbour Analysis" (NNA) was ook uitgevoer om die akkuraatheid van die statistiese ontleding te verhoog. Korog inskrywings wat in die 2016 proef die beste biomassa opbrengs gelewer het, was ingesluit in die proef van 2017. Die inskrywings wat verder goeie opbrengs geproduseer het, was geselekteer vir verdere evaluasie. Gedurende die eerste sny het korog 'n gemiddeld van 1 000 kg.ha-1 biomassa opbrengs gelewer, wat 'n aanduiding was van die gewas se potensiaal om as weidingsgewas te dien omdat dit in die meeste gevalle beter gedoen het as sy mededingers. In die sagte deegstadium het die biomassa-opbrengste 12 000 kg.ha-1 oorskry. Tydens die proewe was die oorerflikheid vir die eienskap droëmateriaalopbrengs gemeet, met oorerflikheidswaardes wat gewissel het tussen 0,14 tot 0,88 oor die tydperk van die sagte deeg stadium. Die KV van die proewe het gewissel van 7,95% tot 24,8%. Aan die einde van die tweede jaar van die studie was vyf hawer inskrywings, een gars en agt korog geselekteer om die voedingswaardes te evalueer. Die voedingsparameters waarvolgens die voedingswaarde geevalueer was, was proteïen, vesel, vet, vog en droëmateriaal. Sekere inskrywings was onder die top-inskrywings wat biomassa-opbrengs sowel as voedingswaarde betref. Deur hierdie studie word die hipotese aanvaar dat korog 'n hoë potensiaal het om as alternatiewe gewas te dien in gewasrotasies. Die inskrywings "AgBeacon", "Snel", "US2017", "US2018" en "17USTRITEL020" is geselekteer om as moontlike ouers ingesluit te word in 'n formele teelprogram wat daarop gemik is om die biomassa-opbrengs te verbeter. Uit hierdie studie blyk die behoefte aan verdere navorsing vir verdere verbetering van korog. Verdere navorsing is nodig wat gefokus is op die verhoging van die biomassa-opbrengs van korog sowel as verbetering van voedingswaarde, wat benutting van die gewas in die bedryf sal aanhelp.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/108021
This item appears in the following collections: