Concomitant phytonutrient and transcriptome analysis of mature fruit and leaf tissues of tomato (<i>Solanum lycopersicum</i> L. cv. Oregon Spring) grown using organic and conventional fertilizer

Enhanced levels of antioxidants, phenolic compounds, carotenoids and vitamin C have been reported for several crops grown under organic fertilizer, albeit with yield penalties. As organic agricultural practices continue to grow and find favor it is critical to gain an understanding of the molecular underpinnings of the factors that limit the yields in organically farmed crops. Concomitant phytochemical and transcriptomic analysis was performed on mature fruit and leaf tissues derived from Solanum lycopersicum L. ‘Oregon Spring’ grown under organic and conventional fertilizer conditions to evaluate the following hypotheses. 1. Organic soil fertilizer management results in greater allocation of photosynthetically derived resources to the synthesis of secondary metabolites than to plant growth, and 2. Genes involved in changes in the accumulation of phytonutrients under organic fertilizer regime will exhibit differential expression, and that the growth under different fertilizer treatments will elicit a differential response from the tomato genome. Both these hypotheses were supported, suggesting an adjustment of the metabolic and genomic activity of the plant in response to different fertilizers. Organic fertilizer treatment showed an activation of photoinhibitory processes through differential activation of nitrogen transport and assimilation genes resulting in higher accumulation of phytonutrients. This information can be used to identify alleles for breeding crops that allow for efficient utilization of organic inputs.已有研究表明，施用有机肥的多种作物其抗氧化物质、酚类化合物、类胡萝卜素及维生素C含量均显著提升，但此类种植模式往往伴随产量损失。随着有机农业实践持续发展并获得广泛认可，解析限制有机种植作物产量的分子机制，已成为至关重要的研究课题。本研究针对有机肥料与常规肥料种植条件下培育的番茄（Solanum lycopersicum L.）‘俄勒冈春’品种的成熟果实及叶片组织，同步开展植物化学组与转录组分析，以验证如下两项假说：其一，与植物生长相比，有机肥土壤管理模式会将更多光合来源的资源分配至次生代谢产物的合成；其二，有机肥管理模式下参与植物营养素积累变化的基因会呈现差异表达，且不同肥料处理的种植条件会诱导番茄基因组产生差异化响应。两项假说均得到验证，表明植物会针对不同肥料类型调整其代谢与基因组活性。有机肥处理通过差异激活氮转运与同化基因，激活了光抑制过程，进而提升了植物营养素的积累量。本研究结果可用于筛选可高效利用有机投入物的作物育种等位基因。