Improved resistance to preharvest sprouting in modern bread wheat (Triticum aestivum. L.) can be achieved via the introgression of grain dormancy and would reduce both the incidence and severity of damage due to unfavourable weather at harvest. The dormancy phenotype is strongly influenced by environmental factors making selection difficult and time consuming and this trait an obvious candidate for marker assisted selection. A highly significant Quantitative Trait Locus (QTL) associated with grain dormancy and located on chromosome 4A was identified in three bread wheat genotypes, two white- and one red-grained, of diverse origin. Flanking SSR markers on either side of the putative dormancy gene were identified and validated in an additional population involving one of the dormant genotypes. Genotypes containing the 4A QTL varied in dormancy phenotype from dormant to intermediate dormant. Based on a comparison between dormant red- and white-grained genotypes, together with a white-grained mutant derived from the red-grained genotype, it is concluded that the 4A QTL is a critical component of dormancy; associated with at least an intermediate dormancy on its own and a dormant phenotype when combined with the R gene in the red-grained genotype and as yet unidentified gene(s) in the white-grained genotypes. These additional genes appeared to be different in AUS1408 and SW95-50213.

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Abstract. Synthetic hexaploid wheat (SHW) represents a valuable source of new resistances to a range of biotic and abiotic stresses. Exploitation of these resistances in bread wheat breeding programs, however, is not necessarily straightforward and requires an assessment of potential negative effects on quality particularly from the genomes contributed by the durum parents used in the development of SHW. In particular, high-molecular-weight glutenin subunits (HMW-GS) 6+8 that are common in durum and SHW but, in bread wheat, are present at only a very low frequency in Chinese wheat cultivars and landraces and as a result there is only limited data on the effects of HMW-GS 6+8 on wheat processing quality and especially on dry, white Chinese noodles (DWCN). In this study, 131 recombinant inbred lines (RIL) were developed from a cross between a CIMMYT SHW 'Syn-CD780' and an elite Sichuan common wheat cultivar 'ChuanYu12'.The aim of this study was to investigate the effect of the HMW glutenin allele, Glu-B1d (6+8), from SHW on quality-related characteristics and DWCN making quality compared with the alternate allele Glu-B1u (7*+8). The RIL and parents were grown in three environments and analysed for 21 quality and noodle test parameters. Results showed the effect of Glu-B1d depended on both the parameters tested and glutenin subunit background contributed by alleles at the Glu-A1 and Glu-D1 loci. RIL with the Glu-B1d allele v. those with the Glu-B1u had significantly higher Zeleny sedimentation volume and falling number in the subunit backgrounds Glu-A1c/Glu-D1a and Glu-A1c/Glu-D1ah, significantly higher L* of dry flour in the background Glu-A1a/Glu-D1a; significantly higher dough development time, dough stability time, breakdown time and lower softness in both backgrounds Glu-A1c/Glu-D1a and Glu-A1c/GluD1ah; significantly higher values of most rapid visco analysis parameters, especially pronounced in the background GluA1c/Glu-D1a. The RIL with the Glu-B1d allele also showed significantly higher (P < 0.05) noodle total score (NTS) in the Glu-A1a/Glu-D1a background and significantly higher (P < 0.01) NTS and most components of sensory assessment in the Glu-A1c/Glu-D1a background. Overall, the results indicate that the allele Glu-B1d, 6+8, from synthetic hexaploids could, in general, have a positive influence on most bread wheat quality parameters and DWCN noodle-making, particularly when combined with particular glutenin subunits at Glu-A1 and Glu-D1.Additional keywords: high-molecular-weight glutenin subunit, recombinant inbred line, synthetic hexaploid wheat.

Abstract:Sichuan is an important wheat producing province of China where severe stripe rust epidemics occur annually. Developing high-yielding wheat varieties with good and stable stripe rust resistance is a foremost breeding objective of all breeding programs. Because minor gene based adult-plant resistance (APR) is considered durable, a shuttle breeding program between Sichuan Academy of Agricultural Sciences (SAAS) and CIMMYT was initiated in 2000 to transfer APR identified in CIMMYT wheats to wheat germplasm adapted in Sichuan. During 2007-2009, a total of 669 advanced generation lines obtained from this shuttle breeding effort were provided to the Plant Protection Research Institute, SAAS for official multi-environment stripe rust tests, and 231 elite lines were characterized for yield performance by the agronomists at the Crop Research Institute, SAAS. Between 11-39% lines were highly resistant depending on the year of testing and 17 (7.3%) lines had 5% or higher yields than the check mean. The adapted resistant lines are being used by various breeding programs to enhance resistance diversity, and three lines are being tested in National or Provincial Yield Trials for possible releases.

High cost of microalgae harvesting impeded the development of algae biofuel technology and wastewater treatment to commercial practicality. Filamentous fungi and microalgae could form pellets under certain culture condition and the symbiosis system is a novel method to reduce the cost of microalgae harvesting. In this paper, effects of glucose and yeast cream content on the pelletization behaviors of fungi and fungi-Chlorella sp. symbiosis system are investigated. The results show that the fungi are easier to form pellets with introduction of glucose or yeast cream.