RRC ID 19669
Author Kusumi K, Hirotsuka S, Kumamaru T, Iba K.
Title Increased leaf photosynthesis caused by elevated stomatal conductance in a rice mutant deficient in SLAC1, a guard cell anion channel protein.
Journal J Exp Bot
Abstract In rice (Oryza sativa L.), leaf photosynthesis is known to be highly correlated with stomatal conductance; however, it remains unclear whether stomatal conductance dominantly limits the photosynthetic rate. SLAC1 is a stomatal anion channel protein controlling stomatal closure in response to environmental [CO(2)]. In order to examine stomatal limitations to photosynthesis, a SLAC1-deficient mutant of rice was isolated and characterized. A TILLING screen of N-methyl-N-nitrosourea-derived mutant lines was conducted for the rice SLAC1 orthologue gene Os04g0674700, and four mutant lines containing mutations within the open reading frame were obtained. A second screen using an infrared thermography camera revealed that one of the mutants, named slac1, had a constitutive low leaf temperature phenotype. Measurement of leaf gas exchange showed that slac1 plants grown in the greenhouse had significantly higher stomatal conductance (g (s)), rates of photosynthesis (A), and ratios of internal [CO(2)] to ambient [CO(2)] (C (i)/C (a)) compared with wild-type plants, whereas there was no significant difference in the response of photosynthesis to internal [CO(2)] (A/C (i) curves). These observations demonstrate that in well-watered conditions, stomatal conductance is a major determinant of photosynthetic rate in rice.
Volume 63(15)
Pages 5635-44
Published 2012-9-1
DOI 10.1093/jxb/ers216
PII ers216
PMID 22915747
PMC PMC3444276
MeSH Amino Acid Sequence Anions / metabolism Carbon / analysis Carbon / metabolism Carbon Dioxide / metabolism Molecular Sequence Data Mutation Nitrogen / analysis Nitrogen / metabolism Oryza / genetics* Oryza / metabolism Oryza / physiology Phenotype Photosynthesis / physiology* Phylogeny Plant Leaves / genetics Plant Leaves / metabolism Plant Leaves / physiology Plant Proteins / genetics Plant Proteins / metabolism* Plant Shoots / genetics Plant Shoots / metabolism Plant Shoots / physiology Plant Stomata / genetics Plant Stomata / metabolism Plant Stomata / physiology Plant Transpiration / physiology* Seedlings / genetics Seedlings / metabolism Seedlings / physiology Sequence Alignment Thermography
IF 5.908
Times Cited 69
Rice Induced Mutation Lines