Author
FATIMA, TAHIRA - FORMER ARS EMPLOYEE | |
SOBOLEV, ANATOLY - NATIONAL RESEARCH COUNCIL - ITALY | |
TEASDALE, JOHN - FORMER ARS EMPLOYEE | |
Kramer, Matthew | |
Bunce, James | |
HANDA, AVTAR - PURDUE UNIVERSITY | |
Mattoo, Autar |
Submitted to: Metabolomics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/4/2016 Publication Date: 5/11/2016 Citation: Fatima, T., Sobolev, A., Teasdale, J.R., Kramer, M.H., Bunce, J.A., Handa, A.K., Mattoo, A.K. 2016. Fruit metabolite networks in engineered and non-engineered tomato genotypes reveal fluidity in a hormone and agroecosystem specific manner. Metabolomics. 12:103. Interpretive Summary: Multiple strategies have been explored throughout the world to meet food security. These include molecular breeding, transgenic genotype development, reduced-tillage crop production, modification of the soil environment with cover crops or polyethylene mulches and tunnels, and organic farming. Understanding gene-environment interactions (“crosstalk”) is necessary for the next wave of advances to meet food security. This manuscript addresses our objective to assess the influence of genetic background, agroecosystem environment, and their interaction on the growth and primary metabolism of transgenic lines. To provide an index of cellular metabolism, we assessed the impact and compatibility of select agroecosystems including the reduced-till cover crop based alternative system on the genotype-specific metabolomic variables in seven tomato genotypes. Also, we developed a statistical approach based on characterizing the changes in the simple correlations between metabolite pairs among subsets of data using both formal statistics and graphics for visualizing changes in the networks. We show here that specific metabolite relationships and networks in tomato fruit metabolites are fluid and are influenced both by the genotype and the agroecosystem environment. This research on metabolic changes reinforces the need to take into account the variations imposed by agroecosystems on ‘novel’ and other engineered genotypes for variables like yield, metabolite/nutrient content and longevity. Such studies can contribute the needed information to agricultural sustainability by segregating genotypes that have robust agronomic and other traits under different agroecosystems. This research is valuable to geneticists, agronomists, horticulturists and physiologists as well as to other scientists conducting basic research on connection between genes and metabolism. Technical Abstract: Multiple strategies have been explored throughout the world to meet food security. These include molecular breeding, transgenic genotype development, reduced-tillage crop production, modification of the soil environment with cover crops or polyethylene mulches and tunnels, and organic farming. Understanding gene-environment interactions (“crosstalk”) is necessary for the next wave of advances. Using isogenic reverse genetic mutations and selected mulch based cropping systems, we evaluated the influence of crosstalk between the genetic background (high polyamine lines; low methyl jasmonate line; low ethylene line; and isogenic genotypes carrying double transgenic events) and environments (different mulching systems) on the tomato fruit metabolome. We show that enhanced spermidine/spermine (Spd/Spm) exhibit strong effects on amino acids, Krebs cycle intermediates and energy charge (ADP + ATP) in ripening fruits; these effects are also seen when growing these genotypes under different mulches (hairy vetch, bare soil, plastic black mulch and rye). Univariate, multivariate, and network analyses suggested that the metabolic response to high polyamine genotypes was similar to the response to hairy vetch cover crop mulch. Changes in primary metabolites of genotypes mutated for the deficiency of ethylene or methyl jasmonate were unique under all growth conditions and, as expected, opposite of results in the high polyamine genotypes. Analysis of the isogenic genotypes carrying double transgenic events demonstrated that high Spd/Spm trait dominates the low ethylene and low jasmonate mutations under field conditions. An inverse relationship of several metabolites occurred for low ethylene versus low methyl jasmonate genotypes. The metabolite network analysis used in this study differs from those done previously because we focused on how the relationships among metabolites changed under different conditions; we show that these networks are more dynamic than previously believed. |