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Grains of 12 accessions of Triticum timopheevii (Zhuk.) Zhuk. ssp. timopheevii (AAGG, 2n = 4x = 28) and one bread wheat cultivar Chinese Spring (CS) and one durum wheat cultivar Langdon (LDN) grown across two years were analyzed for grain iron (Fe) and zinc (Zn) concentrations. All the 12 tested T. timopheevii ssp. timopheevii genotypes showed significantly higher concentration of grain Fe and Zn than CS and LDN. Aboundant genetic variability of both the Fe and Zn concentrations was observed among the T. timopheevii ssp. timopheevii accessions, averagely varied from 47.06 to 90.26 mg kg−1 and from 30.05 to 65.91 mg kg−1, respectively. Their grain Fe and Zn concentrations between years exhibited a significantly positive correlation with the correlation coefficients r = 0.895 and r = 0.891, respectively, indicating the highly genetic stability. Flag leaf possessed twice or three times higher concentrations for both Fe and Zn than grain, and a significantly high positive correlation appeared between the two organs with r = 0.648 for Fe and r = 0.957 for Zn concentrations, respectively, suggesting flag leaves might be indirectly used for evaluating grain Zn and Fe contents. Significant correlations occurred between grain Fe and Zn concentrations, and between grain Zn concentration and the two agronomic traits of plant height and number of spikelets per spike. Both the concentrations were not related to seed size or weight as well as NAM-G1 gene, implying the higher grain Fe and Zn concentrations of T. timopheevii ssp. timopheevii species are not ascribed to concentration effects of seed and the genetic control of NAM-G1 gene. There might be some other biological factors impacting the grain’s Zn and Fe concentrations. These results indicated T. timopheevii ssp. timopheevii species might be a promising genetic resource with high Fe and Zn concentrations for the biofortification of current wheat cultivars.

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In this article, we give some reviews concerning negative probabilities model and quasi-infinitely divisible at the beginning. We next extend Feller’s characterization of discrete infinitely divisible distributions to signed discrete infinitely divisible distributions, which are discrete pseudo compound Poisson (DPCP) distributions with connections to the Lévy-Wiener theorem. This is a special case of an open problem which is proposed by Sato (2014), Chaumont and Yor (2012). An analogous result involving characteristic functions is shown for signed integer-valued infinitely divisible distributions. We show that many distributions are DPCP by the non-zero p.g.f. property, such as the mixed Poisson distribution and fractional Poisson process. DPCP has some bizarre properties, and one is that the parameter λ in the DPCP class cannot be arbitrarily small.

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Abstract  

Molar heat capacities (C p,m) of aspirin were precisely measured with a small sample precision automated adiabatic calorimeter over the temperature range from 78 to 383 K. No phase transition was observed in this temperature region. The polynomial function of C p,m vs. T was established in the light of the low-temperature heat capacity measurements and least square fitting method. The corresponding function is as follows: for 78 K≤T≤383 K, C p,m/J mol-1 K-1=19.086X 4+15.951X 3-5.2548X 2+90.192X+176.65, [X=(T-230.50/152.5)]. The thermodynamic functions on the base of the reference temperature of 298.15 K, {ΔH TH 298.15} and {S T-S 298.15}, were derived. Combustion energy of aspirin (Δc U m) was determined by static bomb combustion calorimeter. Enthalpy of combustion (Δc H o m) and enthalpy of formation (Δf H o m) were derived through Δc U m as - (3945.262.63) kJ mol-1 and - (736.411.30) kJ mol-1, respectively.

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Cereal Research Communications
Authors: Z. L. Li, D. D. Wu, H. Y. Li, G. Chen, W. G. Cao, S. Z. Ning, D. C. Liu, and L. Q. Zhang

Gliadin is a main component of gluten proteins that affect functional properties of bread making and contributes to the viscous nature of doughs. In this study, thirteen novel ω-gliadin genes were identified in several Triticum species, which encode the ARH-, ATDand ATN-type proteins. Two novel types of ω-gliadins: ATD- and ATN- have not yet been reported. The lengths of 13 sequences were ranged from 927 to 1269 bp and the deduced mature proteins were varied from 309 to 414 residues. All 13 genes were pseudogenes because of the presence of internal stop codons. The primary structure of these ω-gliadin genes included a signal peptide, a conserved N-terminal domain, a repetitive domain and a conserved C-terminus. In this paper, we first characterize ω-gliadin genes from T. timopheevi ssp. timopheevi and T. timopheevi ssp. araraticum. The ω-gliadin gene variation and the evolutionary relationship of ω-gliadin family genes were also discussed.

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Cereal Research Communications
Authors: G. Chen, M.H. Zhang, X.J. Liu, J.Y. Fu, H.Y. Li, M. Hao, S.Z. Ning, Z.W. Yuan, Z.H. Yan, B.H. Wu, D.C. Liu, and L.Q. Zhang

Premature termination codons (PTCs) are an important reason for the silence of highmolecular- weight glutenin subunits in Triticum species. Although the Glu-A1y gene is generally silent in common wheat, we here isolated an expressed Glu-A1y gene containing a PTC, named 1Ay8.3, from Triticum monococcum ssp. monococcum (AmAm, 2n = 2x = 14). Despite the presence of a PTC (TAG) at base pair positions 1879–1881 in the C-terminal coding region, this did not obviously affect 1Ay8.3 expression in seeds. This was demonstrated by the fact that when the PTC TAG of 1Ay8.3 was mutated to the CAG codon, the mutant in Escherichia coli bacterial cells expressed the same subunit as in the seeds. However, in E. coli, 1Ay8.3 containing the PTC expressed a truncated protein with faster electrophoretic mobility than that in seeds, suggesting that PTC translation termination suppression probably occurs in vivo (seeds) but not in vitro (E. coli). This may represent one of only a few reports on the PTC termination suppression phenomenon in genes.

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In this study, we employed electron microscopy to investigate the cytogenetic and embryologic mechanisms of parthenogenesis induced in the 1BL/1RS male sterile lines of wheat. Analysis of the root tips and acid polyacrylamide gel electrophoresis indicated that all of the male sterile lines and their maintainer lines were 1BL/1RS translocation lines, whereas the restorer lines were non-1BL/1RS translocation lines. Furthermore, the chromosomes of 1BL/1RS wheat lines with T. aestivum cytoplasm and Aegilops cytoplasm (include Ae. kotschyi, Ae. ventricosa, Ae. variabilis) paired abnormally at different rates during meiotic metaphase I (MMI). The translocated segment size of the 1RS chromosome and the specific nuclear–alloplasm interaction impaired the pairing of homologous chromosome in the background of the specific Aegilops cytoplasm at MMI. In addition, the frequency of abnormal chromosomal pairing was directly affected by the frequency of haploid production induced by parthenogenesis. The results of this study provide significant insights into the mechanism of parthenogenesis, which is probably due to the abnormal fertilization of synergid cells in alloplasmic 1BL/1RS wheat.

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It is well demonstrated that wheat-rye 1BL/1RS translocated chromosome leads to some valuable novel traits such as disease resistance, high yield and functional stay-green after anthesis. To understand the physiological mechanism of 1BL/1RS translocation responsible for osmotic stress, two wheat cultivars, CN12 and CN17, carrying the translocated chromosome and MY11 without the translocated chromosome were employed in the study. During 5-day osmotic stress, fresh weight inhibition, chlorophyll content, soluble protein content, MDA concentration, antioxidant enzymes activity and free polyamines content were examined. CN12 and CN17, especially cultivar CN17, registered greater biomass and minor oxidative damage compared with their wheat parent. Meanwhile, the concentration of Spd and Spm in CN17 was significantly higher than the others. In addition, we found a positive correlation of fresh weight inhibition (FWI) and Put concentration, and a negative one with the parameters (Spd + Spm): Put ratio, indicating the importance of higher polyamine (Spd and Spm) accumulation on the adaptation to osmotic stress. Therefore, we proposed that the accumulation of higher polyamines (Spd and Spm) should play an important role on the adaptation of 1BL/1RS translocation lines to osmotic stress and might be important factors for the origin of novel traits introduced by 1BL/1RS.

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Cereal Research Communications
Authors: Z.L. Li, H.Y. Li, G. Chen, X.J. Liu, C.L. Kou, S.Z. Ning, Z.W. Yuan, M. Hao, D.C. Liu, and L.Q. Zhang

Seven Glu-A1 m allelic variants of the Glu-A1 m x genes in Triticum monococcum ssp. monococcum, designated as 1Ax2.1 a, 1Ax2.1 b, 1Ax2.1 c, 1Ax2.1 d, 1Ax2.1 e, 1Ax2.1 f, and 1Ax2.1 g were characterized. Their authenticity was confirmed by successful expression of the coding regions in E. coli, and except for the 1Ax2.1 a with the presence of internal stop codons at position of 313 aa, all correspond to the subunit in seeds. However, all the active six genes had a same DNA size although their encoding subunits showed different molecular weight. Our study indicated that amino acid residue substitutions rather than previously frequently reported insertions/deletions played an important role on the subunit evolution of these Glu-A1 m x alleles. Since variation in the Glu-A1x locus in common wheat is rare, these novel genes at the Glu-A1 m x can be used as candidate genes for further wheat quality improvement.

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Chromosome segment substitution lines (CSSLs) are powerful tools to combine naturally occurring genetic variants with favorable alleles in the same genetic backgrounds of elite cultivars. An elite CSSL Z322-1-10 was identified from advanced backcrosses between a japonica cultivar Nipponbare and an elite indica restorer Xihui 18 by SSR marker-assisted selection (MAS). The Z322-1-10 line carries five substitution segments distributed on chromosomes 1, 2, 5, 6 and 10 with an average length of 4.80 Mb. Spikilets per panicle, 1000-grain weight, grain length in the Z322-1-10 line are significantly higher than those in Nipponbare. Quantitative trait loci (QTLs) were identified and mapped for nine agronomic traits in an F3 population derived from the cross between Nipponbare and Z322-1-10 using the restricted maximum likelihood (REML) method in the HPMIXED procedure of SAS. We detected 13 QTLs whose effect ranging from 2.45% to 44.17% in terms of phenotypic variance explained. Of the 13 loci detected, three are major QTL (qGL1, qGW5-1 and qRLW5-1) and they explain 34.68%, 44.17% and 33.05% of the phenotypic variance. The qGL1 locus controls grain length with a typical Mendelian dominance inheritance of 3:1 ratio for long grain to short grain. The already cloned QTL qGW5-1 is linked with a minor QTL for grain width qGW5-2 (13.01%) in the same substitution segment. Similarly, the previously reported qRLW5-1 is also linked with a minor QTL qRLW5-2. Not only the study is important for fine mapping and cloning of the gene qGL1, but also has a great potential for molecular breeding.

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Cereal Research Communications
Authors: N. Niu, Y.X. Bai, S. Liu, Q.D. Zhu, Y.L. Song, S.C. Ma, L.J. Ma, X.L. Wang, G.S. Zhang, and J.W. Wang

Studies of the pollen abortion mechanism in thermo-sensitive male sterile lines may provide a strong foundation for breeding hybrid wheat and establishing a theoretical basis for marker-assisted selection. To investigate the cause of pollen abortion in Bainong thermo – sensitive male sterile (BNS) lines, we analyzed the properties of pollen grains, changes in the tapetum and microspores in different anther developmental stages, and the distribution and deposition of nutrient substances in microspores. We found that tapetum degraded in the early uninucleate stage in sterile BNS (S-BNS), which was earlier than that of fertile BNS (F-BNS) tapetum. Large amounts of insoluble polysaccharides, lipids, and proteins were deposited until the trinucleate pollen stage in the nutritive cells in F-BNS. At the binucleate stage, the vacuoles disappeared and pollen inclusion increased gradually. At the trinucleate stage, these nutrients would help pollen grains mature and participate in fertilization normally. Therefore, early degradation of the tapetum, which inhibits normal microspore development, and the limited content of nutrient substances in pollen may be the main factors responsible for male sterility in BNS lines.

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