The stability of productivity and fruit quality traits of ‘Fuji’ apples on different Rootstocks

Simple item page
dc.contributor.advisorSiboza, Xolani en_ZA
dc.contributor.advisorTheron, Karen en_ZA
dc.contributor.authorNgindi, Buhleen_ZA
dc.contributor.otherStellenbosch University. Faculty of Agrisciences. Dept. of Horticulture.en_ZA
dc.date.accessioned2024-03-04T13:24:38Z
dc.date.accessioned2024-04-26T21:21:58Z
dc.date.available2024-03-04T13:24:38Z
dc.date.available2024-04-26T21:21:58Z
dc.date.issued2024-03
dc.descriptionThesis (MScAgric)--Stellenbosch University, 2024. en_ZA
dc.description.abstractENGLISH ABSTRACT: Rootstocks of apple trees are essential for productive and economical orchards. Rootstocks influence tree architecture, yield, and fruit quality. Most of the current rootstocks used in South African apple orchards lack precocity, are vigorous and not able to overcome some of the challenges faced in these orchards. Some of these challenges include poor soils, lack of winter chill as well as the prevalence of pests and diseases. Thus, productivity is negatively affected. The Geneva rootstocks are being bred to confer pest and disease resistance/tolerance, a range of tree vigour, but highly precocious. In this study, rootstock genotypes were planted in two separate but adjacent plantings, i.e., vigorous rootstocks and dwarfing rootstocks. The Fuji cultivar was evaluated on these genotypes in three different environments across South Africa – Oak Valley Estate and Breëvlei, both in Grabouw, Western Cape, and Helderwater, Eastern Cape. These environments differed in climatic conditions, soil conditions and management practices such as training systems used, irrigation and pruning strategies. The vigorous plantings consisted of MM.109, M.793, M.7 EMLA (control), G.778, G.228 and G.202. The dwarfing plantings comprised of M.9 EMLA, M.9 Nic29, M.7 EMLA (control), G.222, G.778/G.222, G.778/M.9 EMLA, MM.109/G.222, MM.109/M.9 EMLA, M.793/G.222 and M.793/M.9 EMLA. The influence of rootstocks on tree vigour, yield and yield efficiency, and fruit quality traits (mass, diameter, ground colour, red foreground colour, firmness, total soluble solids (TSS) and starch breakdown) was determined. The tendency of ‘Fuji’ apples planted on different rootstocks to bear alternately was investigated from the first year of harvest (2016/2017) to 2020. Rootstock productivity maybe influenced by the genotype (i.e., rootstock and scion), the environment and the interaction between the genotype and environment (GEI). The environment includes soil, climate and management factors. The influence of GEI on tree vigour and productivity was investigated. The presence of GEI complicates selection and requires that the stability and adaptability of genotypes be assessed to select for the most stable and adaptable rootstock genotypes. Stability refers to a genotypes’ ability to behave predictably against environmental fluctuations whilst adaptability refers a genotype’s ability to show high and constant yields in certain environments. For the vigorous rootstocks, GEI was significant (p < 0.001) for all yield traits and was non-significant for tree vigour. The most stable and high-yielding genotype was G.778 based on 2016/20 cumulative yield (149.00 kg/tree) and 2016/20 cumulative yield efficiency (2.39 kg/cm2 TCSA). For the dwarfing rootstocks, the GEI was significant for all yield traits and tree vigour. The most stable and high-yielding dwarfing genotype combinations based on 2016/20 cumulative yield and 2016/20 cumulative yield efficiency were G.778/G.222 and G.778/M.9 EMLA. ‘Fuji’ apples are prone to the development of internal browning during long-term storage. Since rootstocks may influence fruit maturity, the rootstock genotype may influence the occurrence and severity of internal browning. Thus, the influence of rootstocks on the occurrence of internal browning and postharvest fruit quality was investigated. Fruit were stored under controlled atmosphere conditions for 5 months at -0.5 °C, then subsequently moved to regular atmosphere conditions for 6 weeks, after which fruit were subjected to shelf-life conditions. A significant GEI (p < 0.001) on the occurrence of internal browning was obtained. As such, the environment also influenced the occurrence of internal browning. Fruit from trees on Geneva rootstocks (including those with interstems) had higher and more severe incidences of internal browning compared to the industry standards due to the more advanced maturity.en_ZA
dc.description.abstractAFRIKAANSE OPSOMMING: Die gebruik van onderstamme by appelbome is onontbeerlik vir produktiewe en ekonomiese boorde. Onderstamme beïnvloed boomargitektuur, opbrengs en vruggehalte. Die meeste van die onderstamme wat in Suid-Afrika gebruik word, toon ʼn gebrek aan vroegrypheid, is groeikragtig en kan nie sommige van die uitdagings in boorde oorkom nie. Hierdie uitdagings sluit in swak grond, gebrek aan winterkoue, en die teenwoordigheid van peste en plae. Produktiwiteit word derhalwe negatief beïnvloed. Die Geneva-onderstamme word tans gekweek om weerstand/verdraagsaamheid teen die peste en siektes te verhoog, om groeikrag te beheer, en vroegryp te wees. In hierdie studie, genotipes van onderstamme is in twee afsonderlike maar aaneenliggende blokke in boorde gevestig, nl. groeikragtige onderstamme en dwergonderstamme. ‘Fuji’ is geokuleer op hierdie genotipes en is in drie afsonderlike streke in Suid-Afrika geëvalueer nl. op Oak Valley Estate en Breëvlei, beide in Elgin, Wes-Kaap, en Helderwater, Langkloof, Oos-Kaap. Hierdie omgewings het verskil in klimaatstoestande, grondtoestande en bestuurspraktyke soos opleidingstelsels wat gebruik is, besproeiing en snoeistrategieë. Die groeikragtige onderstamme wat gebruik is was MM.109, M793, M.7 EMLA (kontrole), G.778, G.228 en G.202. Die dwergonderstamme was M.9 EMLA, M.9 Nic29, M.7 EMLA (kontrole), G.222, G.778/G.222, G.778/M9 EMLA, MM.109/G.222, MM.109/M.9 EMLA, M.793/G.222 en M.793/M.9 EMLA. Die invloed van die onderstam op boomgroeikragtigheid, opbrengs en opbrengseffektiwiteit, asook vruggehalte-eienskappe (massa, deursnee, agtergrondkleur, rooi voorgrondkleur, fermheid, totale opgeloste vaste stowwe (TSS) en stysel-afbreking) is bepaal. Die neiging van ‘Fuji’-appels wat op die verkillende onderstamme geokuleer is omoor te slaan, is ondersoek, vanaf die eerste jaar van oes (2016/2017) tot 2020. Onderstamproduktiwiteit kan dalk beïnvloed word deur die genotipe (d.w.s. onderstam en bostam), die omgewing en die interaksie tussen die genotipe en die omgewing (GEI). Die omgewing sluit grond, klimaat en bestuursfaktore in. Die invloed van GEI op boom-groeikragtigheid en produktiwiteit is nagevors. Die teenwoordigheid van GEI kompliseer seleksie en vereis dat die stabiliteit en aanpasbaarheid van genotipes geassesseer word om die mees stabiele en aanpasbare onderstamgenotipes te identifiseer. Stabiliteit verwys na 'n genotipe se vermoë om voorspelbaar teen omgewingsskommelinge op te tree, terwyl aanpasbaarheid verwys na 'n genotipe se vermoë om hoë en konstante opbrengste in sekere omgewings te toon. Vir die groeikragtige onderstamme is GEI betekenisvol (p < 0.001) vir al die oeseienskappe, en is nie-betekenisvol vir boomgroeikragtigheid nie. Die mees stabiele genotipe met die hoogste opbrengs gebaseer op kumulatiewe opbrengs en kumulatiewe opbrengseffektiwiteit, was G.778. Onder die dwergonderstamme was GEI betekenisvol oor alle eienskappe en boomgroeikragtigheid. Die mees stabiele dwerggenotipes, gebaseer op 2016/20 kumulatiewe opbrengs en kumulatiewe opbrengseffektiwiteit was G.778/G.222 en G.778/M.9 EMLA. ‘Fuji’-appels is geneig om interne verbruining te ondergaan tydens langtermyn opberging. Aangesien onderstamme vrugrypheid kan beïnvloed, kan die onderstam-genotipe die voorkoms en intensiteit van interne verbruining beïnvloed. Derhalwe is die invloed van onderstamme op die voorkoms van interne verbruining en ná-oesvruggehalte ondersoek. Vrugte is onder gekontroleerde atmosferiese toestande (-0.5 °C) vir 5 maande opgeberg, en daarna vir 6 weke onder normale raklewe toestande gestoor. ʼn Betekenisvolle GEI van die interne verbruining is verkry. Die omgewing het dus ook die voorkoms van interne verbruining beïnvloed. Vrugte van bome op Geneva onderstamme (insluitende die met tussenstamme) het hoër en ernstiger voorkoms van interne verbruining weens gevorderde rypheid getoon in vergelyking met wat in die industrie as vereiste gestel word.af_ZA
dc.description.versionMastersen_ZA
dc.identifier.urihttps://scholar.sun.ac.za/handle/10019.1/130541
dc.language.isoen_ZAen_ZA
dc.language.isoen_ZAen_ZA
dc.publisherStellenbosch : Stellenbosch Universityen_ZA
dc.rights.holderStellenbosch Universityen_ZA
dc.subject.lcshFuji apples -- Breedingen_ZA
dc.subject.lcshApples -- Rootstocks -- South Africaen_ZA
dc.subject.lcshOrchards -- Economic aspects -- South Africaen_ZA
dc.subject.lcshGenotype-environment interactionen_ZA
dc.subject.lcshClimate change mitigation -- Environmental aspectsen_ZA
dc.subject.lcshFruit trees -- Postharvest technologyen_ZA
dc.subject.lcshFruit -- Qualityen_ZA
dc.subject.lcshApples -- Storage -- Quality controlen_ZA
dc.subject.nameUCTDen_ZA
dc.titleThe stability of productivity and fruit quality traits of ‘Fuji’ apples on different Rootstocksen_ZA
dc.typeThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
ngindi_stability_2024.pdf
Size:
9.77 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Masters Degrees (Horticulture)