Combined effects of Wx and SSIIa haplotypes on rice starch physicochemical properties.
BACKGROUND
Wx and SSIIa are central genes for determining starch physicochemical properties and rice endosperm starch is composed of linear amylose, which is entirely synthesized by granule bound starch synthase I (GBSSI, encoded by Wx) and branched amylopectin. In the present study, different haplotypes of rice were examined to investigate the combined effects of pivotal genes in the metabolic chain of starch, Wx and SSIIa.


RESULTS
Wx haplotypes differed in terms of apparent amylose content (AAC) and gel consistency (GC). The I-3 [haplotype I (Int1T/Ex10C) of Wx and haplotype 3 (A-G-TT) of SSIIa] and the I-4 combinations of rice had better eating and cooking qualities (ECQs) with lower AAC, lower gelatinization temperature (GT) and softer GC.


CONCLUSIONS
The characteristic parameters of Rapid Visco-analyser (RVA) could distinguish differences in AAC and GC but not GT. The I-3 and I-4 haplotype combinations of Wx and SSIIa represent key targets for the production of rice with better ECQs. © 2016 Society of Chemical Industry.
Laboratory of Plant Molecular Genetics and Breeding, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China.|Engineering Research Center for Biomass Resource Utilization and Modification of Sichuan Province, 59 Qinglong Road, Mianyang, 621010, China.
Xunchao
X
Xiang
Laboratory of Plant Molecular Genetics and Breeding, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China.
Cuifang
C
Kang
Laboratory of Plant Molecular Genetics and Breeding, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China.
Shunju
S
Xu
Laboratory of Plant Molecular Genetics and Breeding, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China.
Bowen
B
Yang
D000687:Amylopectin / Q000378:metabolism; D000688:Amylose / Q000096:biosynthesis*; D003296:Cooking; D002523:Edible Grain / Q000378:metabolism / Q000592:standards; D056625:Endosperm / Q000378:metabolism*; D005782:Gels; D017343:Genes, Plant; D006239:Haplotypes; D006801:Humans; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D013213:Starch / Q000378:metabolism / Q000592:standards; D013214:Starch Synthase / Q000235:genetics* / Q000378:metabolism; D013696:Temperature
D005782:Gels; D010940:Plant Proteins; C060756:waxy protein, plant; D013213:Starch; D000688:Amylose; D000687:Amylopectin; C434607:granule-bound starch synthase I; D013214:Starch Synthase
Wx gene and SSIIa gene; combined effect; haplotype; rice eating and cooking qualities; starch physicochemical properties