Linking biochemistry and genetics in celery to taste and flavour perceived by consumers: developing a more acceptable product

芹菜特征芹菜Apium Graveolens变种。赛卡金因其独特的风味和质地，作为一种新鲜的产品而广受欢迎。它最初适应沼泽条件，因此倾向于产生中空的茎和叶柄。对这种作物的驯化导致了更多可食用的品种的选择，减少了苦味和强烈的味道。芹菜是饮食中维生素C、K、钠和钾的良好来源(美国农业部，2012年)，并对结直肠癌有很强的保护作用(金福等人，1991年)。它富含类黄酮和酚类化合物(Lin等人，2007年)；后者的氧化会导致切面采后褐变。芹菜中的主要风味化合物是邻苯二甲酸酯，其次是萜烯。Van Wassenhove等人(1990)使用GCMS发现了33种化合物，这些化合物存在于所有四个被测试的热烫芹菜品种中。该项目的目的是开发育种品系和相关的分子标记，以培育出具有更好的采后表现和风味属性的芹菜品种。项目计划。A L Tozer有限公司共有52条线路可供项目使用。我们将选择30个覆盖多样性的品系，并在雷丁的受控环境中种植它们。我们将使用GCMS确定挥发性化合物(如萜类和邻苯二甲酸酯)和非挥发性化合物(如酚类和糖类)的风味特征。从这些数据中，我们将选择6个极端品系=里程碑1(9个月)。我们将进行感官小组评估所选择的极端品系，从而验证生物化学与人类感知的里程碑2(12个月)。我们将开始基于代表生物化学和味道感知广度的连锁亲本生成图谱种群。如果第一次杂交是在第一年，我们应该在第三年=里程碑3(30个月)的F2代。这六个极端品系将于第二年在西班牙和英国种植，从而测试不同环境、土壤类型和季节对选择的生化和感官特性的影响。这项工作将能够评估环境对芹菜风味的影响=里程碑3(24个月)。在第三年，该项目将检查不同植物发育/田间保持时间的风味和生化变化，从而提供关于哪些品系可能提供季节性和感官稳定性的信息=里程碑4(36个月)。消费者小组将被用来评估亲本芹菜品系的喜好(或不喜欢)，亲本世代的转录组测序将被用来组装芹菜基因组。将在F2群体中对SNPs进行评分，并将在第4年制作工作图=里程碑5(40个月)该项目将与G‘s合作，通过其商业加工线在F2代作图群体中加工亲本系和F2代的芹菜。采后品质(坚实度、失重、褐变、茎空洞)和风味生物化学将被分析并用作可被绘制为里程碑6(45个月)的性状。这些特征将提供广泛的QTL，并可能与基于转录组的标记相关联，Tozer可以提炼和推广这些标记，使其超越博士的生命。即使找不到基于转录组的标记，该项目仍将提供生物化学和所需风味特征之间的强烈关联，从而有可能开发基于代谢物特征的新品系。

Celery characteristicsCelery Apium graveolens var. secalinum is popular as a fresh product due to its characteristic flavour and texture. It was originally adapted to marshy conditions, hence its tendency to produce hollow stems and petioles. Domestication of the crop has resulted in the selection of more edible varieties with reduced bitter and strong flavours. Celery is a good source of Vitamins C, K, sodium, and potassium in the diet (USDA, 2012) and has a strong protective effect against colorectal cancer (Jinfu et al., 1991). It is rich in flavonoids and phenolics (Lin et al., 2007); oxidation of the latter causes postharvest browning of cut surfaces. Key flavour compounds in celery are phthalides, and to a lesser degree the terpenes. Van Wassenhove et al (1990) found 33 compounds using GCMS that were present in all four varieties of blanching celery tested. The aim of the project is to develop breeding lines and associated molecular markers that can give rise to a celery variety with improved postharvest performance and flavour attributes. Project plan.A L Tozer Ltd have 52 lines in total available to the project. We will select 30 lines that cover the diversity and grow them in controlled environment at Reading. We will determine flavour profiles of volatile compounds e.g. terpenes and phthalides using GCMS and non-volatile compounds such as phenolics and sugars using LCMS. From these data we will select 6 extreme lines = Milestone 1 (month 9).We will conduct sensory panels to evaluate the selected extreme lines, thus validating the biochemistry against human perception = Milestone 2 (month 12).We will start to generate mapping populations based on linked parents that represent the breadth of biochemistry and flavour perceptions. If the first crosses are made in year 1 we should be at F2 generation by year 3 = Milestone 3 (month 30). The six extreme lines will be grown in Spain and the UK in year 2, thus testing the impact of different environments, soil types and seasons on the biochemical and sensory properties of the selections. This work will enable evaluation of the environmental impact on celery flavour = Milestone 3 (month 24).In year three the project will examine changes in flavour and biochemistry at different plant development/field holding times, thus providing information on which lines are likely to impart seasonal and sensory stability = Milestone 4 (month 36). Consumer panels will be used to assess liking (or otherwise) of the parental celery lines.Transcriptome sequencing of the parental generations will be used to assemble a celery genome. SNPs will be scored in the F2 population and a working map will be produced = Milestone 5 (month 40)In year 4 the project will collaborate with G's to process celery from the parental lines and in the F2 generation of the mapping population through their commercial processing line. Postharvest quality (firmness, weight loss, browning, stem hollowing) and flavour biochemistry will be analysed and used as traits that can be mapped = Milestone 6 (month 45). These traits will give broad QTL, and possible association with transcriptome based markers that Tozer can refine and take forward beyond the life of this PhD. Even if transcriptome based markers cannot be found the project will still provide strong associations between biochemistry and desirable flavour profile, such that development of new lines based on metabolite profile will be possible.