Genetic and physiological traits for internal phosphorus utilization efficiency in rice

• Published in: PloS one Vol. 15; no. 11; p. e0241842
• Main Authors: Adem, Getnet Dino, Ueda, Yoshiaki, Hayes, Patrick Enrico, Wissuwa, Matthias
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 05.11.2020; Public Library of Science (PLoS)
• Subjects: Agricultural production; Agricultural research; Aquatic ecosystems; Biology and Life Sciences; Biomass; Efficiency; Environmental impact; Experiments; Fertilizers; Galactolipids; Gene expression; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Genes; Genetic aspects; Genotype; Genotypes; Humidity; Leaves; Lipids; Livestock; Mineral metabolism; Nonrenewable resources; Oryza - genetics; Oryza - growth & development; Oryza - metabolism; Phospholipids; Phosphorus; Phosphorus (Nutrient); Phosphorus - metabolism; Physiological aspects; Physiology; Plant biochemical genetics; Plant growth; Plant Leaves - genetics; Plant Leaves - growth & development; Plant Leaves - metabolism; Plant metabolism; Plant Proteins - genetics; Plant Roots - genetics; Plant Roots - growth & development; Plant Roots - metabolism; Renewable resources; Research and Analysis Methods; Rice; Rock phosphate; Seeds; Japan
• DOI: 10.1371/journal.pone.0241842
• ISSN: 1932-6203

Phosphorus (P) is an essential macronutrient for plant growth and development. Phosphorus is usually applied as fertilizer obtained from rock phosphate which is a non-renewable resource. Therefore, developing rice varieties that can use P more efficiently is crucial. Here, we investigated genotypic differences in traits related to internal Phosphorus Utilization Efficiency (PUE) in five rice genotypes grown under P-deficient conditions. P-efficient rice genotypes showed higher total biomass. This was partly due to higher root biomass, which in turn relied on preferential allocation of P to roots in these genotypes. Changes in P content and tissue P concentrations were analyzed in individual leaves at different time points. Genotypes belonging to the high-PUE group responded more quickly to P starvation in terms of reducing leaf P concentrations and they were able to reduce these concentrations to a lower level compared to the low-PUE group. Changes in P concentrations were reflected in gene expression levels for genes involved in lipid remodeling. Sulfolipid ( OsSQD2 ) and galactolipid ( OsMGD and OsDGD ) synthesis-related genes were generally induced due to P starvation with most pronounced up-regulation in OsDGD1 and OsMGD3 , but patterns differed between genotypes. A significantly higher expression of OsDGD5 and OsMGD1 & 2 was detected in the youngest fully expanded leaf of the high-PUE genotype group, whereas expression levels were reversed in older leaves. This pattern would confirm that P efficient genotypes react faster to P starvation in terms of freeing P for redistribution to growing tissues and replacing phospholipids with galactolipids in younger leaves may contribute to this aspect.