A diallel study of Secale cereale

Moller, Ernst Lodewicus (2016-12)

Thesis (MSc)--Stellenbosch University, 2016.

Thesis

ENGLISH ABSTRACT: Rye (Secale cereale) originated and was domesticated in the fertile cresent in the Middel East. It has been part of the human staple diet for thousands of years in those areas as well as Eastern Europe. It is known for its ability to grow and produce grain and animal feed in harsh environments. Therefore, as a result of its hardiness, rye is cultivated in many countries across the globe. In a rapid changing environment, due to climate change and human population growth, the importance of food security cannot be over emphasised. Therefore, this study aimed to select superior parent lines for the following characteristics: days to heading, plant length, spike number, thousand kernel weight and yield to be used in the Stellenbosch University’s Plant Breeding programme. In the first part of the study seed, from eight randomly selected plants from a synthetic population, were planted in planting pots. Due to it’s outbreeding nature and high degree of inbreeding depression, the first filial from each individual plant are half-siblings. DNA from three half-siblings from each parent line was extracted to determine variance at molecular level. Eight clones were made from the half-sibling showing the greatest variance for each line. In the second part of the study these clones were planted according to a Griffing full diallel mating design in all possible combinations. The progeny of these crosses was planted in a random block design with three repititions and the results were measured and compared to determine the general as well as specific combining ability of the diverent lines. Althouth no significant differences were observed, promising general combiners were identified for days to heading, plant length, spike number, thousand kernel weight and yield. One line may also be considered as a potential parent line for use in a synthetic population to improve qualities for animal fodder and yield. It was also found that one cross performed better than the means for four of the five traits and may therefore be considered for use in a hybrid production program.

AFRIKAANS OPSOMMING: Die oorsprong en domestikasie van Rog (Secale cereale) kan gevind word in die vrugbare halfmaangebied van die Midde Ooste. Dit is alreeds vir duisende jare deel van die mens se stapelvoedsel in hierdie streek, sowel as Oos-Europa en is bekend vir die vermoë om graan en dierevoer in moeilike omgewings te produseer. As gevolg van sy gehardheid, word rog in baie lande regoor die wêreld verbou. In 'n snelveranderende omgewing, as gevolg van klimaatsverandering en menslike bevolkingsgroei, kan die belangrikheid van voedselsekuriteit nie oorbeklemtoon word nie. Hierdie studie is dus daarop gemik om beter ouerlyne vir die volgende eienskappe te selekteer: dae tot aarvorming, plant lengte, aantal are per plant, duisend korrel massa en opbrengs vir verdere gebruik in die Universiteit Stellenbosch se Planteteelt program. In die eerste deel van die studie is saad, van agt lukraak gekose plante uit 'n sintetiese bevolking, in plant potte geplant. As gevolg van die kruistelende aard van die gewas, asook die hoë mate van inteelt depressie is die eerste filiaal van elke individuele plant dus half sibbe. DNA ekstraksies vanuit drie half sibbe van elke ouerlyn is gemaak om variansie op molekulêre vlak te bepaal. Die halfsib, van elke ouerlyn, wat die grootste variasie getoon het is agt keer gekloon. In die tweede deel van die studie was hierdie klone geplant volgens 'n Griffing volle dialeel kruisingsplan in alle moontlike kruisings kombinasies. Die nageslag van hierdie kruisings is geplant in ewekansige blok ontwerp met drie herhalings en die resultate is gemeet en vergelyk om die algemene- sowel as spesifieke kombinerings vermoë van die onderskeie lyne te bepaal. Alhoewel geen betekenisvolle verskille gevind is nie, is die belowendste algemene kombineerdes geïdentifiseer vir dae tot aarvorming, plant lengte, aantal are per plant, duisend korrel massa en opbrengs. Een lyn, met beter eienskappe vir dierevoer en opbrengs is ook geïdentifiseer as 'n potensiële ouerlyn vir gebruik in 'n sintetiese populasie. Daar is ook bevind dat een van die kruisings beter presteer vir vier van die vyf eienskappe en kan daarom oorweeg word vir gebruik as ‘n ouerlyn vir baster produksies.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/100091
This item appears in the following collections: