Waxy allelic diversity in common millet （Panicum miliaceum L.） in China

摘要

cqvip:A set of 132 accessions of common millet,Panicum miliaceum L.,from 12 provinces of China were assessed for endosperm starch type(waxy or non-waxy)using I_2-KI staining,amylose and amylopectin contents using the dual-wavelength colorimetric method,and genotype of Waxy genes conditioning amylose content by gene sequencing.Endosperm starch content varied from57.69%to 74.70%,while the amylose and amylopectin contents of the starch ranged from 0 to23.29%and from 41.99%to 70.24%,respectively.Sequencing two Wx genes,including Wx-L(intron 5-exon 7 and intron 8–9)and Wx-S(exon 9–intron 10)revealed several polymorphisms(S_0,S_(-15),L_C,L_F,L_Y).Marker M5-R11 linking to the Wx-S gene may be used to discriminate waxy common millet accessions from non-waxy ones.Among the 132 accessions,68 with the S_(-15)allele had waxy endosperm starch with the amylose content range 0–2.58%and 64 accessions with the S_0allele had non-waxy endosperm starch with amylose content range 3.94%–23.29%.Five genotypes including S_(-15)/L_F(45%of the accessions),S_0/L_F(25%),S_0/L_Y(12%),S_0/L_C(11%),and S_(-15)/L_Y(7%)were identified.Six new SNPs were detected at the Wx-L locus.These results will facilitate common millet breeding,especially of cultivars free of amylose.