Production of aneuhaploid and euhaploid sporocytes by meiotic restitution in fertile hybrids between durum wheat Langdon chromosome substitution lines and Aegilops tauschii

Fertile F1 hybrids were obtained between durum wheat （Triticum durum Desf.） Langdon （LDN） and its 10 disomic substitution （LDN DS） lines with Aegilops tauschii accession AS60 without embryo rescue. Selfed seedset rates for hybrids of LDN with AS60 were 36.87% and 49.45% in 2005 and 2006, respectively. Similar or higher selfed seedset rates were observed in the hybrids of 1D （1A）, 1D （1B）, 3D （3A）, 4D （4B）, 7D （7A）, and 2D （2B） with AS60, while lower in hybrids of 3D （3B） ＋ 3BL, 5D （5A） ＋ 5AL, 5D （5B） ＋ 5B and 6D （6B） ＋ 6BS with AS60 compared with the hybrids of LDN with AS60. Observation of male gametogenesis showed that meiotic restitution, both first-division restitution （FDR） and single-division meiosis （SDM） resulted in the formation of functional unreduced gametes, which in turn produced seeds. Both euhaploid and aneuhaploid gametes were produced in F1 hybrids. This suggested a strategy to simultaneously transfer and locate major genes from the ancestral species T. turgidum or Ae. tauschii. Moreover, there was no significant difference in the aneuhaploid rates between the F1 hybrids of LDN and LDN DS lines with AS60, suggesting that meiotic pairing between the two D chromosomes in the hybrids of LDN DS lines with AS60 did not promote the formation of aneuhaploid gametes.

Phylogenetic analysis of click beetles(Coleoptera: Elateridae) based upon 28S rDNA: phylogeny and classification

Elateridae（click beetles） is the largest family within the Elateroidea and is abundant worldwide. However, their phylogenetic relationships remain uncertain; older studies based on the external morphology of adults and larvae led to divergent classification systems. Many tribes, genera, and even subfamilies remain controversial. Partial sequences of 28S ribosomal DNA（rDNA） were used to investigate the phylogeny of click beetles. Sequences of 28S rDNA from 80 different click beetle species collected from different locations across China were determined along with those of another 86 Elateridae species and 14 outgroup species. The aligned data were analyzed by neighbor joining, maximum parsimony, maximum likelihood, and Bayesian analyses. All methods produced a nearly consistent basal topology that was partially congruent with those of previous studies based on adult and larval morphology as well as molecular data. Overall, the monophyly of Elateridae was supported. The family was divided into five clades, Denticollinae, Negastriinae, Cardiophorinae, Pyrophorinae, Oestodinae, and Elaterinae. Senodonia is traditionally considered a member of Elateridae, but this study indicated that it was more closely related to Lycidae. The position of the outgroup family Lampyridae also differed from its placement in previous research. In addition to confirming the Elateridae as monophyletic, we concluded that Oxynopterinae, Pityobiinae, and Hypnoidinae should be merged into Denticollinae; Conoderinae and Agrypninae should be regarded as subgroups of Pyrophorinae; and Melanotinae should be classified as a tribe of Elaterinae. Additional species should be sampled in future studies to confirm this reclassification.

GC-MS Analysis of Metabolites in Filling Grains of Rice-Tartary Buckwheat (Fagopyrum tataricum) in Comparison to Conventional Tartary Buckwheat

Rice-Tartary buckwheat(RTB)is a special germplasm of Tartary buckwheat.In this study,the appraisal of taste quality between RTB and conventional Tartary buckwheat(CTB)was presented,and the metabolites in kernels at three typical grain filling stage(GFS)were investigated.Unlike CTB,RTB showed thin shell seeds without longitudinal furrows at maturity,which was easily artificially dehulled.Sense organ test indicated that RTB exhibited better taste quality because of the higher values of appearance,viscosity,taste and summary were appraised.In total,92 metabolites were identified in kernels using GM-MS metabolomics platform.The levels of most metabolites changed greatly during grain filling and a large numbers of metabolite-metabolite correlations were found by Pearson correlation coefficient analysis.ANOVA analysis identified 61 differentially expressed metabolites between RTB and CTB,while Venn diagram analysis screened 35 common differential metabolites.Compared with CTB,RTB showed similar levels of lysine and methionine,indicated that RTB own excellent nutritional value.Additionally,RTB exhibited significantly up-regulated levels of most sweeteners(sugars and polyols),which might contribute to better taste.This work provides the first comprehensive metabolomics analysis of kernels between RTB and CTB,which may potentially provide theoretical basis for further research.