Impact of elevated CO2 and phosphorus nutrition on mineral composition and cooking quality of rice

• Published in: Plant Physiology Reports 2021-12, Vol.26 (4), p.687-698
• Main Authors: Raviteja, Doddagatta Hanumanthappa, Kumar, Tarun, Sharma, Sandeep, Kumar, Arun, Singh, Madan Pal, Pandey, Renu
• Format: Article
• Language: English
• Subjects: Biomedical and Life Sciences; Cell Biology; Life Sciences; Original Article; Plant Biochemistry; Plant Ecology; Plant Genetics and Genomics; Plant Physiology; Plant Sciences
• ISSN: 2662-253X; 2662-2548
• DOI: 10.1007/s40502-021-00623-y

To mitigate the adverse effects of nutrient stress under elevated atmospheric [CO 2 ] on grain mineral composition and cooking quality, selection of crop varieties that are productive and maintain grain nutritional quality is important. Rice ( Oryza sativa L.) varieties, IR64-Pup1.1, IR64, and Kasalath, were grown in open top chambers (OTC) with elevated [CO 2 ] (700 ± 50 ppm), OTC with ambient [CO 2 ], and open control-ambient [CO 2 ] with two levels of phosphorus (P), low (7.96 mg P kg −1 soil) and sufficient (22.9 mg P kg −1 soil) to study the interactive effects of P and [CO 2 ] on grain quality. Grain quality traits varied significantly among varieties under elevated [CO 2 ] but P nutrition effect was not significant. The concentration of N reduced significantly but P, K, Mg, and Ca increased under elevated [CO 2 ] compared to open control-ambient [CO 2 ]. Micronutrients Cu, Mn, Ni, and Zn increased significantly except Fe, while Al increased by > 50% under elevated [CO 2 ] compared to open control-ambient [CO 2 ]. Free sugars (glucose, fructose, and maltose) increased 3 to 5-folds but protein decreased significantly as C:N ratio altered at elevated [CO 2 ]. Among cooking qualities, elevated [CO 2 ] increased amylose and gel consistency resulting in increased viscosity of cold paste gel of cooked rice and boiling time of rice grain. Grain dimension was not affected by elevated [CO 2 ] or P level. Among varieties, IR64-Pup1.1 performed better under elevated [CO 2 ] irrespective of P levels as compared to Kasalath and IR64. Ours is the first report on grain quality assessment of IR64-Pup1.1 under elevated [CO 2 ] and low P availability.