Registration of Common Wheat Germplasm with Mutations inSBEIIGenes Conferring Increased Grain Amylose and Resistant Starch Content.
Starch present in the endosperm of common wheat (Triticum aestivumL.) grains is an important source of carbohydrates worldwide. Starches with a greater proportion of amylose have increased levels of resistant starch, a dietary fiber that can provide human health benefits. Induced mutations inSTARCH BRANCHING ENZYME II(SBEII) genes in wheat are associated with increased amylose and resistant starch. Ethyl methane sulfonate mutations inSBEIIaandSBEIIbparalogs were combined in the hexaploid wheat cultivar Lassik. Four mutant combinations were generated:SBEIIa/b-AB (Reg. No. GP-997, PI 675644);SBEIIa/b-A,SBEIIa-D (Reg. No. GP-998, PI 675645);SBEIIa/b-B,SBEIIa-D (Reg. No. GP-999, PI 675646); andSBEIIa/b-AB,SBEIIa-D (Reg. No. GP-1000, PI 675647). TheSBEIImutant lines were compared with a wild-type control in a greenhouse and field experiment. The quintuple mutant line (SBEIIa/b-AB,SBEIIa-D) presented significant increases in both amylose (51% greenhouse; 63% field) and resistant starch (947% greenhouse; 1057% field) relative to the control. A decrease in total starch content (7.8%) was observed in the field experiment. The quintuple mutant also differed in starch viscosity parameters. Registration of the hexaploid wheatSBEII-mutant lines by University of California, Davis can help expedite the development of common wheat cultivars with increased amylose and resistant starch content.
Dep. of Plant Sciences, Univ. of California, Davis, CA 95616.
André
A
Schönhofen
Dep. of Plant Sciences, Univ. of California, Davis, CA 95616.
Brittany
B
Hazard
Dep. of Plant Sciences, Univ. of California, Davis, CA 95616.
Xiaoqin
X
Zhang
Dep. of Plant Sciences, Univ. of California, Davis, CA 95616.
Jorge
J
Dubcovsky