气候风险对普麦期货价格波动的影响

本文通过构造我国小麦主产区的天气标准化指数衡量气候风险,实证研究了气候风险对我国期货市场普麦期货价格波动性的影响。研究发现,极端高温、极端低温和强降水等气候风险事件的发生会显著提高期货价格的波动性。机制分析表明,气候风险除了直接影响普麦期货价格波动性外,还通过影响现货价格波动性间接对普麦期货价格波动性造成正向影响。本文研究为农产品期货市场应对气候风险、促进农业生产、保障粮食安全提供了思路。

A Unique Aegilops tauschii Genotype Needless to Immature Embryo Culture in Cross with Wheat

Common or bread wheat ( Triticum aestivum L., AABBDD, 2n=42) originated ca. 8 000 years ago from hybridization of tetraploid wheat ( Triticum turgidum L., AABB, 2n=28) and diploid Aegilops tauschii Coss. (DD, 2n=14). An essential prerequisite for this evolutionary step is that the natural hybrids between tetraploid wheat and diploid Aegilops tauschii can produce relatively many filled seeds which germinated well. In this study, without special techniques, e.g. immature embryo culture, out of 22 Ae. tauschii accessions, the genotype AS60 produced relatively many filled seeds which germinated well. The seed germination percentages in the crosses of Ae. tauschii ×tetraploid wheat, tetraploid wheat× Ae. tauschii and Ae. tauschii ×common wheat were, respectively, 50.0%, 57.1% and 45.5%. It seems that Ae. tauschii accession AS60 has a unique genotype which facilitate hybrid seed development and viability, and which meets with the prerequisite for wheat evolutionary. Furthermore, the significance of this finding for common wheat improvement and evolution was discussed.

Primary Identification of Alien Chromatin in T911289,a Maintainer of Wheat Male Sterile Line with Cytoplasm of Aegilops kotschyi

The genomic composition of 1911289, a wheat ( Tritium aestivum L.) maintainer of K-CMS, was examined by several methods, such as genomic in situ hybridization (GISH), biochemical marking, and DNA molecular marking. The results got by GISH and PCR amplification of dispersed rye-specific repetitive DNA sequence suggested that the alien chromatin in T911289 derived from rye. Specifically PCR amplification of the rye-specific microsatellite primers (SCM9) and seed storage protein analysis indicated that the alien chromatin in T911289 had developed from the short arm of 1R chromosome of rye (1RS). PCR amplification by using microsatellite primers locating on 1BS and seed storage protein analysis also revealed that 1911289 had lost the arm of 1BS or a small distal segment of it. We conclude that T911289 is a heterogeneous population which displays two distinct different types of translocation, i.e. the Robertsonian translocation and small segment translocation. The Robertsonian translocation type observed in our study is different from the 1BL/1RS translocation which is widely used in wheat production; it may be a novel and complex translocation form. Though the linkage between the desirable agronomic traits and the deleterious genes expressed as sticky dough has not got broken in T911289, the recovery of small segment translocation will still benefit the genetic study of wheat and rye.

Characterization of Two Groups of Low_copy and Specific DNA Sequences Isolated from Chromosome 7B of Common Wheat

Recent work revealed that, in the genomes of polyploid wheat, there exists a class of low_copy and chromosome_specific sequences that are labile upon polyploid formation. This class of sequences was proposed to play a critical role in the stabilization and establishment of nascent plant polyploids as new species. To further study this issue, five wheat chromosome 7B_specific sequences, isolated from common wheat (Triticum aestivum L.) by chromosome microdissection, were characterized. The sequences were studied by genomic Southern hybridizations on a collection of polyploid wheats and their diploid progenitors. Four sequences hybridized to all polyploid species, but at the diploid level to only species closely related to the B_genome of polyploid wheat. This indicates that these sequences originated with the divergence of the diploid species, and was then vertically transmitted to polyploids. One sequence hybridized to all species at both the diploid and polyploid levels, suggesting its elimination after the polyploid wheat formation. The hybridization of this sequence to two synthetic polyploid wheats indicated that sequence elimination is a rapid event and probably related to methylation status of the sequence. Based on the above results, we suggest that selective changes of low_copy sequences occur rapidly after polyploid formation, which may contribute to the differentiation of chromosomes in newly formed allopolyploid wheats.

2018年部分地区强筋小麦及普通小麦品质分析

本研究主要针对河南、河北、山东省内规模生产的强筋小麦如西农979、新麦26、师栾02-1、济南17以及河南省内中筋小麦为分析对象,进行全面系统的品质质量分析,并对强筋小麦进行烘焙实验,及时了解2018年度小麦主产区新季强筋麦和河南省内中筋小麦的质量和品质情况,掌握这些品种的品质质量状况,为小麦加工企业和食品加工企业生产作指导。

Optimization of plant regeneration system in vitro culture in wheat

Studies were carried out to establish an efficient regeneration system of three bread wheat cultivars. Results showed induction medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) had a higher plantlet regeneration frequency than Piclorm, with an average frequency of 54% in all treatments. Optimal condition for different genotypic rice was as following: induction medium (MSS 3AA/2) with 0.5 mg L-1 2,4-D, regeneration medium (R) with 0.01 mg L-1 2,4-D and 3 mg L-1 KT. The average regeneration frequency reached 83.3% under the condition. Correlation analysis showed that root differentiation, in different level, correlated with green spot regeneration, and with the number of regenerated plants per callus. No correlation was found between green spots regenerated and the numbers of plants regenerated per callus.

Cloning and Sequence Analysis of PBF Encoding Genes from Hexaploid Common Wheat Chinese Spring (Triticum aestivum L.)

[Objective] This study aimed to investigate the polymorphism of PBF en- coding genes from common wheat Chinese Spring （Triticum aestivum L.）. [Method] Using common wheat Chinese Spring as the experimental material, gene-specific primers were designed and applied to amplify the genomic DNA of Chinese Spring. PCR products were isolated, purified and ligated into the cloning vector. Positive clones were randomly selected for sequencing. A series of softwares including DNAMAN, Signalp, PSIPRED, Nuc_PLoc and MEGA were employed for sequence assembly and alignment, signal peptide prediction, primary and secondary structure prediction, as well as analyses of subcellular location and phylogenetic relationships between the PBF family members in Poaceae. [Result] Twenty-five target sequences were obtained from the genome of hexaploid common wheat Chinese Spring, which were classified into three clusters based on the sequence similarity. SNPs exist at two loci of the subunit, resulting in the change of encoded amino acid residues and affecting the secondary structure of final product encoded. [Conclusion] PBF encoding sequences are extremely conservative in Chinese Spring with certain variations. This study provides theoretical reference to evaluate the expression efficiency of wheat storage proteins.

Development of marker Ms2 gene with a blue seed in durum and common wheat

In order to marker dominant nuclear gene Ms2 with a blue grain, a 4E disomic addition line ＇xiaoyanlanli＇（2n=44, AABBDD＋4EII） as the male parent to pollinate with male-sterile plants of durum wheat, controlled by a dominant nuclear gene Ms2, and a durum wheat line 89-2343 with Ms2 and blue seed marker on the same addition chromosome was developed. The genotype 89-2343 was crossed and backcrossed with a common wheat genotype 7739-3 to produce male fertile plants with blue seeds （MFP-BS）. To combine the blue seed marker, dwarf male-sterile plants carrying RhtlO and Ms2 were fertilized by pollen from selected MFP-BS. At last, the combination of blue seed marker, Ms2 and RhtlO was successfully produced. The segregation ratio of male sterility, seed color as well as chromosome configurations of the combinations suggested that the blue seed marker, Ms2 and RhtlO were located on the same chromosome. Cytological analysis indicated that the male sterile wheat line with a blue seed marker was 43 in chromosome number, with an additional chromosome. The transmission rate for blue seed male-sterile plants was 22.1% in common. In addition, the potential value for blue marker sterile lines in wheat breeding and hybrid production is discussed.

Co-residence in Denmark in 1801

The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is household and family. The census is divided by these lines and therefore calculations of household size and complexity are straight forward and this clearly gives one side of the picture. A totally different side is co-residence analysis. This is not straight forward, but because of the standardisation it is doable. By this means, you get a picture of the likelihood that a person of a given age group lives together with specific relatives. It gives an insight into a central part of living conditions and it gives a picture of differences between sexes and urbanisations. The paper brings the two ways of description together and shows that each has something to contribute to the picture of the Danes.

基于文献分析的麦冬潜在功效探讨

通过考察麦冬在古代本草文献、古代方剂和《中华人民共和国药典(2010年版,一部)》(简称《中国药典》)中所载功用,确认古本草中记载的麦冬核心功用和古代方剂对其应用与《中国药典》记录基本一致,而由古本草文献总结出来的清热泻火、解毒消痈、驻颜、健胃消食、消痞散满、益精种子、止痛等潜在功能,以及古代含麦冬复方所治热病、伤寒、疮疡、虚损、呕吐、中风、痞满、头痛等病症,并未被《中国药典》收录。结合实验研究和当今临床应用,可以确认驻颜、平肝熄风、消痞散满、清热泻火、益精种子是麦冬的潜在功效。

Effect of Atmospheric CO_2 Enrichment on Soil Respiration in Winter Wheat Growing Seasons of a Rice-Wheat Rotation System

Studies on the effect of elevated CO2 on C dynamics in cultivated croplands are critical to a better understanding of the C cycling in response to climate change in agroecosystems. To evaluate the effects of elevated CO2 and different N fertilizer application levels on soil respiration, winter wheat （Triticum aestivum L. cv. Yangmai 14） plants were exposed to either ambient CO2 or elevated CO2 （ambient [CO2] ＋ 200 μmol mol-1）, under N fertilizer application levels of 112.5 and 225 kg N ha-1 （as low N and normal N subtreatments, respectively）, for two growing seasons （2006-2007 and 2007-2008） in a rice-winter wheat rotation system typical in China. A split-plot design was adopted. A root exclusion method was used to partition soil respiration （RS） into heterotrophic respiration （RH） and autotrophic respiration （RA）. Atmospheric CO2 enrichment increased seasonal cumulative RS by 11.8% at low N and 5.6% at normal N when averaged over two growing seasons. Elevated CO2 significantly enhanced （P 〈 0.05） RS （12.7%）, mainly due to the increase in RH （caused by decomposition of larger amounts of rice residue under elevated CO2） during a relative dry season in 2007-2008. Higher N supply also enhanced RS under ambient and elevated CO2. In the 2007-2008 season, normal N treatment had a significant positive effect （P 〈 0.01） on seasonal cumulative RS relative to low N treatment when averaged across CO2 levels （16.3%）. A significant increase in RA was mainly responsible for the enhanced RS under higher N supply. The correlation （r2） between RH and soil temperature was stronger （P 〈 0.001） than that between RS and soil temperature when averaged across all treatments in both seasons. Seasonal patterns of RA may be more closely related to the plant phenology than soil temperature. The Q10 （the multiplier to the respiration rate for a 10 ℃ increase in soil temperature） values of RS and RH were not affected by elevated CO2 or higher N supply. These results mainly suggested that the increase in RS at elevated CO2 depended on the input of rice residue, and the increase in RS at higher N supply was due to stimulated root growth and concomitant increase in RA during the wheat growing portion of a rice-winter wheat rotation system.