title: An indica rice genotype showed a similar yield enhancement to that of hybrid rice under free air carbon dioxide enrichment.
abstract: Although the rice growth response to FACE (free-air CO2 enrichment) has been widely studied and is considered important within the scientific community, few studies have attempted to examine the effects of FACE on the yield of indica rice, which is typically the parent of indica hybrids in China. The effects of FACE on the yield, yield components, biomass, N uptake and leaf photosynthesis of Yangdao 6 Hao (an indica rice) in China were examined over 2 years. The grain yield increased over 30%, the panicle number increased 12.4% on average, and the spikelet number per panicle also showed an average increase of 8.2% at elevated CO2. FACE caused a significant enhancement in both the filled spikelet percentage (+5.9%) and the individual grain weight (+3.0%). Compared with three prior FACE studies on rice, a similar enhancement of yield in hybrid indica was shown under FACE, with much a higher value than for the japonica rice cultivar (approximately + 13%) because of indica's stronger sink generation and N uptake capacity, which help coordinate the C/N balance to avoid photosynthetic acclimation. The high enhancement of the indica rice yield under FACE holds promise for improved cultivar selection for future food security.
authors.affiliation: 1] State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, East Beijing Road, Nanjing, 210008, PR China [2] International Center for Ecology, Meteorology and Environment, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China.
authors.forename: Chunwu
authors.initials: C
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, East Beijing Road, Nanjing, 210008, PR China.
authors.forename: Xi
authors.initials: X
authors.lastname: Xu
authors.affiliation: International Center for Ecology, Meteorology and Environment, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: International Center for Ecology, Meteorology and Environment, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, East Beijing Road, Nanjing, 210008, PR China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
mesh_terms: D018533:Biomass; D002245:Carbon Dioxide; D002678:Chimera; D002681:China; D005838:Genotype; D009584:Nitrogen / Q000378:metabolism; D012275:Oryza / Q000235:genetics* / Q000254:growth & development* / Q000502:physiology; D010788:Photosynthesis; D018515:Plant Leaves / Q000502:physiology; D018520:Plant Shoots / Q000254:growth & development
chemical_list: D002245:Carbon Dioxide; D009584:Nitrogen