Metabolite profiling of nutrient-deficiency tolerant and nutrient-deficiency sensitive maize genotypes

4^th International Conference and Exhibition on Metabolomics & Systems Biology

April 27-29, 2015 Philadelphia, USA

Arshid Hussain, Altaf Ahmad and Muhammad Iqbal

Posters-Accepted Abstracts: Metabolomics

Abstract :

We have reported differential metabolic profiling of nutrient-deficiency and nutrient-deficiency sensitive maize (Zea mays L.) genotypes under the regimes of nitrogen (N) and phosphorus (P) deficiency and recovery conditions. The plants were grown hydroponically with +N+P, -N-P, +N-P and -N+P conditions. Metabolites profiling of leaf was carried using GCMS and LC-MS. The results showed that there are significant changes in the metabolite profiling by nutrient stress. While the accumulation of di- and trisaccharides (maltose, sucrose and raffinose) increased, and the level of phosphate containing sugars like glucose-3-PO4, fructose-1,5-bisphosphate and inositol-1-PO4 decreases. It may be due to less consumption of phosphorus and rescue phosphorus from small phosphorus containing metabolites like organic acids. It was also observed that there is sharp increase in almost half of the amino acids mostly asparagine and glutamine and reduction in the levels of aspartate and glutamate, this may be due to protein degradation and repression of protein synthesis. During nitrogen limiting condition plants produce ammonia by converting asparagine, glutamine and glycine into aspartate, glutamate and serine respectively and hence acclimatize in the nutrient stress condition. The same trend was found in the amino acid content as reveled from the quantitative analysis of amino acids by HPLC. This study will help us how plants adapt to nutrient deficient conditions and survive by partitioning metabolites. Thus, we will be able to minimize the use of nitrate and phosphorus fertilizers and help in preventing the nitrate pollution and eutrophication of water bodies caused by inflow of phosphorus into them. In summary, plant metabolomics is a priceless tool for studying the plant genotypes that are exposed to different perturbations (genetic, environmental or modified genome).