No QTL was previously found on chromosomes 1DL, 4AL and 7BL in common wheat, implying that the present QTL for content of A-type starch Apoptosis Compound Library in vivo granules are new. However, the QTL were not consistently detected across environments and thus other populations or materials should be used in QTL or association mapping to validate these findings. It was concluded that A-type and B-type starch granules were controlled by different genes[32]. Although the relative quantity reflects the granule size distribution and is relatively easy to estimate. Percentage volume is not a suitable parameter for direct comparison of QTL conferring
the two types of granules. Therefore, the specific diameters, numbers and weights of A-type and B-type starch granules should be examined in the future. Starch granule size and RVA parameters are important factors in determining starch function. In a previous study, RVA parameters were mapped with the same RIL population selleck chemicals [31]. Compared to the previous results, Qga.caas-1DL was located near
QTL for sedimentation value and mixograph parameters and the marker for Dx5 + Dy10, where a QTL for palate, stickiness and smoothness of Chinese dry noodle was also mapped [33], indicating that these parameters are related to each other and may have pleiotropic effects on noodle quality. The QTL for both starch properties and dough tolerance may contribute to quality improvement. In addition, Batey et al. [24] mapped a QTL for peak viscosity on chromosome 7BL in the same interval as Qga.caas-7BL. Therefore, content of A-starch granules is closely related to RVA parameters. Many enzymes are involved in starch biosynthesis.
The genes for the key enzyme involved in amylose synthesis, granule-bound starch synthase I (GBSS I), were identified on chromosomes 7AS, 4AL and 7DS [34]. It was reported that partially waxy and waxy wheats had less A-type starch granules and more B-type starch granules than non-waxy wheats [35]. GBSS I was found to be responsible for the ratio of A-type to B-type starch granules [1]. In this study, however, both PH82-2 and O-methylated flavonoid Neixiang 188 have wild type Wx-A1, Wx-B1 and Wx-D1 alleles and no QTL was found at these loci. Soluble starch synthase may control starch granule size distribution in the early stage of grain filling [1]. SS III and SS IV (soluble starch synthase) genes were located on common wheat homoeologous group 1 chromosomes [36] and [37], and it was reported that SS IV affected starch granule formation in Arabidopsis thaliana [38]. In addition, the genes for ADP-glucose pyrophosphorylase low subunit, SS I and SS II, and branching enzymes (SBE I and SBE II) were located on homoeologous group 7 chromosomes [39], [40], [41] and [42]. Starch branching enzymes were associated with A-type starch granules [7].