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Fe and Zn deficiency are widespread worldwide. As wheat is the primary food for the majority of the world people, producing wheat grains with high mineral content can ameliorate the problem of mineral hunger. However, the genetic variation available for breeders is limited. The aim of this study was to assess the genetic variation in grain Fe and Zn contents in 47 synthetic hexaploid wheats and to identify marker loci associated with Fe and Zn contents. We measured the grain Fe and Zn contents using inductively coupled plasma atomic emission spectroscopy and performed genotyping using SSR markers. The results showed considerable genetic variation for these minerals. We identified three lines with high Fe and Zn contents and six quantitative trait loci of which three were associated with Fe content and the other three with Zn content. The minerals showed positive phenotypic and genotypic correlation and high heritability (>60%). The ratio of the σg² to the σgxe² was ≥1 for the two mineral contents indicating that breeding for increasing mineral content within the synthetic lines is possible. The synthetic wheat lines identified in this study are valuable genetic resources, and can be utilized for breeding wheat cultivars with high mineral content. [ABSTRACT FROM AUTHOR]

Kernel texture (grain hardness) in common wheat (Triticum aestivumL.) is of primary technological importance and is largely determined by puroindoline gene sequence and expression. We investigated the puroindoline haplotypes of 246 Asian common wheat varieties. All but three were conclusively characterized for puroindoline a and b haplotypes. Of the total, 174 possessed the soft Pina-D1a/Pinb-D1a?wild-type? gene sequences with SKCS hardness indexes (HI) ranging from 13.5 to 61.8. Among the remaining 72 varieties with HIs of 56.1?97.8, nearly half (30) were Pina-D1a/Pinb-D1b, 4 were Pina-D1a/Pinb-D1c, 19 were Pina-D1a/Pinb-D1p, 10 were Pina-D1b/Pinb-D1a(?a-null?), 3 were Pina-D1l/Pinb-D1a, 2 possessed a new C-to-T SNP mutation at position 382, which is tentatively designated Pinb-D1ab, 1 was a ?double null? with neither puroindoline a nor b expressed and no PCR-detectable gene sequence, and 3 had undetermined/ambiguous puroindoline a sequence but possessed Pinb-D1a. The double null was the hardest of all varieties tested with an HI of 97.8. The frequency of soft and hard varieties and puroindoline hardness haplotype varied depending on the origin of the varieties. The lowest frequency of hard varieties occurred in Korea and south-western Japan. Tibet and Pakistan also had low frequencies of hard varieties. The highest frequency of hard varieties appeared in north-east China followed by north-west China and Nepal. Within Asia, the Pinb-D1pallele appears in a region extending from north-eastern China through Inner Mongolia, north-western China, Xinjiang and Tibet, with the greatest frequency in north-western China. This allele was also present in Pakistan and Afghanistan, but not found in Japan, and may have been dispersed along the ?Silk Road?. All three Pina-D1lvarieties came from China. The newly discovered SNP originated in Afghanistan and the ?double null? in Xinjiang. [ABSTRACT FROM AUTHOR]