Study On The Aroma Components Of Apple Red Bud Sports And The Enzyme Activity Related To Fatty Acid Metabolism

Bud sport selection breeding is selecting the best and is the effective way to improveexisting varieties of individual adverse characters. Red bud sport varieties accounted for morethan70%in the bud sport varieties which having been reported.Depth study of the red budmutation mechanism had great significance to the effective improvement of the applevarieties. To this end, based on a number of red strains change and its control material, wefirst identified them by molecular markers in this study,We also analyzed and evaluated thearoma compounds and studied the metabolic mechanism and regularity of the flavoringsubstances. All of this was aim to provide basic information for exploring the red bud sportsapple mechanism and provided a reference for quality apple bud sport breeding. The mainresults were as follows:1. The29materials were identified by AFLP molecular markers technique.64pairs ofprimers augmented1512stripes;using the SimQual program solves the DICE similaritycoefficient matrix for the original matrix and achieved the similarity coefficient matrix forreceiving the dendrogram. It could be judged by dendrogram, the sport and the mother plantshad clearly separation. We have identified its bud sport to provide a molecular basis forfollow-up sport of selection.2.Apple aroma components were analyzed using solid phase microextraction (SPME)and gas chromatography-mass spectrometry (GC/MS) technologies. The effects on the resultsunder different conditions such as fibers, extraction temperature, extraction time anddesorption time were discussed here. The results showed:①The selected scheme for thearoma contraction in apple fruits was using DVB/CAR/PDMS(50/30um) fiber, under50℃for35min, then desorpted at a high temperature for2min, by which the aroma could beabsorbed effectively.②Reproducibility analysis of the selected scheme showed that thevariation factors of the main aroma components were less than10%,most of which were5%.The results showed good reproducibility.3.Using the selected scheme, the aroma components in the ripe apples were comparedbetween4red bud sports derived from ‘Fuji’,‘Ralls’ and ‘Red fuji’ and their mother treesrespectively. These work provided some fundamental materials for the study on the sportsformation mechanisms and their identification. The results showed:①8categories,including116types of aroma components were identified from the ripe fruits in the8applecultivars. There were67types of esters, which accounted for57.8%of all the components. ②There were no regular changes in the types of aroma components between the bud sportsand their mother trees, excepted that the contents of common components of the8applecultivars, total contents of characteristic aroma components, esters contents and total contentsof aroma were significantly higher in the bud sports than their mother trees respectively. Theresults were accordant with the tasting identification.4Four kinds of related enzyme activities and accumulation of fatty acids of Aromasynthesis of fatty acids metabolic pathways were measured on Ralls apple and its red budsport.①There were little changes or volatility trend which could rise and fall sometims inLOX、HPL、ADH on Ralls apple and its red bud sport, The trend of the activity of AAT wasfirst slightly increased then decreased on Ralls apple, but gradual advanced on its red budsport, The four enzyme activities in mature stage were increased and higher than that ofcontrol, the control had a downward trend on its red bud sport;②The fatty acidaccumulation displayed each period of each sample of unsaturated fatty acids weresignificantly higher than that of the saturated fatty acid content during fruit development onRalls apple and its red bud sport,the red bud sport and the control of the total fatty acidaccumulation volume showed decreased first and then increased again downward tendency,bud sport finally declined more rapidly;③In the late stage of fruit development of red budsport,the four enzyme activities showed a rising trend and higher than the control, While theenzyme activity increased accelerated pathway of fatty acid metabolism, and this was alsoassociated with the total fatty acid accumulation declined in bud fruit at the same time.