Research-PGR: Decoding the Volatile Aroma of Tomato Fruits

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

Tomatoes are an important source of nutrition worldwide, providing vitamins and minerals to the diet. Although tomatoes are a critical part of a balanced diet, consumers are often displeased with the flavor of modern tomatoes purchased from supermarkets. Better tasting tomatoes result in increased consumption and improved overall consumer health. Different tomatoes vary tremendously in flavors with some that are highly liked or not at all by consumers. This natural diversity is largely found in tomatoes that are unsuitable for large-scale production because of reduced fruit size, yield and plant appearance that negatively impact profitability for growers. Key components of tomato flavor are the volatile aroma compounds. However, the genetic inheritance and the biochemistry of many aroma compounds in tomato are unknown. This project will aim to find novel characteristics of volatile production in ripe fruit which will ultimately lead to better tasting tomatoes. Identifying these missing components will facilitate breeding efforts for modern varieties with improved flavor. In addition, the next generation of scientists will be trained in current methods of biochemistry, genetics and genomics. Bioinformatics workshops for high school biology and math teachers will improve education and create interest in careers in STEM fields. Survival of the species in terms of seed dispersal is critically dependent on the metabolic pathways that regulate specialized volatile accumulation in ripening fruits. In tomato, genes affecting these pathways often encode metabolic enzymes that differ in gene structure and activity among related red-fruited species. A subset of these are also targets of selection during domestication and improvement of tomato. Yet, key enzymes and regulatory genes in pathways to volatiles that are derived from branched chain amino acids, phenylalanine, and those that belong to the acetate ester category are not well known. The main goal of this research project is to validate, characterize and valorize novel genes in tomato fruit volatile production in the selected pathways by applying integrative genetic, molecular, and biochemical approaches. The information from improved GWAS and bi-parental mapping studies will be used to prioritize candidate genes for specific fruit volatile loci. Candidate genes will be validated by enzymatic assays, CRISPR knockouts and fine mapping of loci in segregating populations. Outreach to high school math and biology teachers will include a workshop on bioinformatics methods. High school students will be exposed to bioinformatics, creating interest in careers in STEM fields. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.