Inverkan av transgena grundstammar på fruktkvaliteten hos icke-transgena äppelsorten ’Jonagold’

Abstract: Gene technology has become more and more attractive in plant breeding during the last twenty years. This is probably because it can readily improve the existing commercial cultivars that have only one or a few drawbacks by modifying one or a few genes without changing the main genetic constitution. In this regard, gene technology is more effective than conventional breeding.The aim of this project was to analyze the fruit quality of the non-transgenic apple scion ‘Jonagold’ grafted on non-transgenic and rolB-transgenic apple rootstocks. The rootstocks used were M9-rolB1, M9-rolB2, M26-rolB and non-transgenic controls M9 and M26. The fruit quality parameters analyzed were size, weight, colour, firmness, total soluble sugar (TSS), acid (TA) content, the ratio of TSS to TA, vitamin C and total phenols.The results showed that M26-rolB had larger fruits than the control M26, while M9-rolB1 and M9-rolB2 had higher sugar content, and M9-rolB1 showed higher firmness. These differences are positive for the fruit quality. The rest of the analyzed parameters did not differ significantly between the transgenic rootstocks and the control. It is uncertain that the differences observed are due to rolB or other factors such as crop load and micro climate. Further studies are required to confirm this.The conclusion from this study is that rolB does not obviously influence the fruit quality of apple cultivar ‘Jonagold’ grafted on the transgenic rootstocks of M9 and M26 .Therefore the gene could be used for improving the rooting capacity of rootstocks for commercial production, consequently increasing the production efficiency.