Growth, seed yield and nutritional characteristics of pigeonpea grown under elevated CO2 atmosphere

In the present study, we have analyzed the seed yield and seed quality of pigeonpea grown under elevated CO2. Pigeonpea was grown for its complete life cycle in open top chambers under elevated CO2 (600 µmol/mol) and atmospheric ambient CO2 (400 µmol/mol). The growth, biomass and seed yield were increased under elevated CO2 when compared to plants grown at ambient CO2 concentrations. The mature seeds were collected after 120 days for various biochemical analyses to determine their nutritional quality. The biochemical analyses indicated that elevated CO2 grown pigeonpea seeds did not show any significant decrease in nitrogen and protein contents but showed an increase in total carbohydrates. The metabolomics of seeds revealed changes in sugars, amino acids, organic acids and fatty acid levels under elevated CO2 growth. The seeds collected from elevated CO2 grown pigeonpea showed higher levels of essential amino acids inferring their better nutritional quality. The total proteome of pigeonpea seed was studied through label-free quantification and recorded an increase in several seed specific proteins including certain stress related proteins in elevated CO2 grown pigeonpea seeds. The proteome and metabolome data demonstrate better seed vigor in elevated CO2 grown pigeonpea.