title: Genetic diversity and QTL mapping of thermostability of limit dextrinase in barley.
abstract: Limit dextrinase (LD) is an essential amylolytic enzyme for the complete degradation of starch, and it is closely associated with malt quality. A survey of 51 cultivated barley and 40 Tibetan wild barley genotypes showed a wide genetic diversity of LD activity and LD thermostability. Compared with cultivated barley, Tibetan wild barley showed lower LD activity and higher LD thermostability. A doubled haploid population composed of 496 DArT and 28 microsatellite markers was used for mapping Quantitative Trait Loci (QTLs). Parental line Yerong showed low LD activity and high LD thermostability, but Franklin exhibited high LD activity and low LD thermostability. Three QTLs associated with thermostable LD were identified. The major QTL is close to the LD gene on chromosome 7H. The two minor QTLs colocalized with previously reported QTLs determining malt-extract and diastatic power on chromosomes 1H and 2H, respectively. These QTLs may be useful for a better understanding of the genetic control of LD activity and LD thermostability in barley.
authors: †Department of Agronomy, Zhejiang Key Lab of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
authors: Xiaolei
authors: X
authors: Wang
authors: †Department of Agronomy, Zhejiang Key Lab of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
authors: Xuelei
authors: X
authors: Zhang
authors: †Department of Agronomy, Zhejiang Key Lab of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
authors: Shengguan
authors: S
authors: Cai
authors: †Department of Agronomy, Zhejiang Key Lab of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
authors: Lingzhen
authors: L
authors: Ye
authors: §Tasmanian Institute of Agriculture, University of Tasmania, P.O. Box 46, Kings Meadows, TAS 7249, Australia.
authors: Meixue
authors: M
authors: Zhou
authors: ‡School of Science and Health, University of Western Sydney, Penrith, NSW 2751, Australia.
authors: Zhonghua
authors: Z
authors: Chen
authors: †Department of Agronomy, Zhejiang Key Lab of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
authors: Guoping
authors: G
authors: Zhang
authors: †Department of Agronomy, Zhejiang Key Lab of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
authors: Fei
authors: F
authors: Dai
mesh_terms: D002874:Chromosome Mapping; D003912:Dextrins / Q000378:metabolism; D004795:Enzyme Stability; D014644:Genetic Variation; D006026:Glycoside Hydrolases / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D001467:Hordeum / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D018895:Microsatellite Repeats; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D040641:Quantitative Trait Loci
chemical_list: D003912:Dextrins; D010940:Plant Proteins; D006026:Glycoside Hydrolases
keywords: Tibetan wild barley; barley (Hordeum vulgare L.); limit dextrinase; quantitative trait locus; thermostability