微卫星标记CSSM18和OB2在5个绵羊群体中多态性研究

选用无角道塞特、萨福克、湖羊、Texel羊与中国美利奴肉用品系组成的试验绵羊群体共计224只,经过耳组织提取基因组DNA,用2对微卫星引物进行PCR扩增,通过电泳分型、凝胶成像系统分析各位点等位基因及全部个体的标记基因型,计算基因频率、多态信息含量(PIC)和杂合度等,从分子水平上分析4个位点的遗传多态性。结果表明,CSSM18和OB2这2个位点的等位基因数分别为18和17,多态信息含量(PIC)为0.722 0~0.862 3,杂合度为0.789 5~0.886 7,均属于高度多态性位点,用于作为与生产性能相关的遗传标记是较理想的。     

软质小麦品质的辅助选择

为建立软质小麦品质的筛选和评价体系,对黄淮麦区和长江下游麦区20个不同硬度小麦品种的Puroindoline基因型以及全麦粉和面粉的部分相关品质性状进行了检测.结果表明,20个品种中,2个品种为Pina-D1b硬质突变型,6个品种为Pinb-D1b硬质突变型,其余12个品种为软质小麦;硬、软质小麦的全麦粉硬度和SDS沉淀值的差异均达到极显著水平,但碱水保持力差异不显著;硬、软质小麦面粉的碱水保持力和溶剂保持力均达到极显著差异.性状间的相关分析表明,全麦粉硬度与SDS沉淀值、面粉的碱水保持力、水溶剂保持力、碳酸钠溶剂保持力、蔗糖溶剂保持力均呈极显著相关,相关系数分别为0.64、0.94、0.94、0.91和0.81,SDS沉淀值与乳酸溶剂保持力相关也极显著,相关系数0.80.这些结果说明Puroindoline基因型检测、全麦粉硬度和SDS沉淀值检测可以作为软质小麦的早代筛选方法.     

Segregation analysis indicates that Puroindoline b-2 variants 2 and 3 are allelic in Triticum aestivum and that a revision to Puroindoline b-2 gene symbolization is indicated

Genetic and kernel texture relationships between Puroindoline b-2 variants 2 and 3 have not been fully established in wheat (Triticum aestivum L.). Here, 480 F₂ plants, derived from three hard spring wheat populations were used to test the segregation of Puroindoline b-2 (Pinb-2) variants 2 and 3. Chi-square analysis indicated that Pinb-2 variants 2 and 3 in all three F₂ populations segregated as a single bi-allelic locus, with segregation ratios fitting a 1:2:1 ratio. Using 448 of the 480 plants derived from these three F₂ populations, the average SKCS hardness index of plants homozygous for Pinb-2 variant 2 vs. those homozygous for variant 3 was not significantly different (67.5 vs. 67.9). Results indicated that plants with Pina-D1b/Pinb-D1a were on average 10.0 Single Kernel Characterization System (SKCS) hardness index units harder than those carrying the Pina-D1a/Pinb-D1b haplotype. In conclusion, Pinb-2 variants 2 and 3 are allelic and exert little effect on kernel texture in hard-kernel T. aestivum germplasm. Further, the designation of Pinb-2v2 and Pinb-2v3 should be changed to Pinb-B2a and Pinb-B2b, respectively. We propose that Pinb-2 variants 1 and 4 of Chinese Spring be designated Pinb-D2a and Pinb-A2a, respectively.     

复等位基因平衡群体熵的性质

研究了复等位基因平衡群体熵的性质 ,并与基因多样度 D、相对信息多样度 S′(A)、相对纯合度信息多样度 S′ J(A)、相对杂合度信息多样度 S′ H(A)及多态信息含量 PIC进行了比较研究。结果表明 ,在表征基因变异与遗传变异上 ,信息论方法与统计学方法具有一致性 ,而且信息论方法还具有信息学含义     

Sources of resistance to tomato spotted wilt virus (TSWV) in cultivated and wild species of Capsicum

Summary The high molecular weight (HMW) subunits of glutenin extracted from flour of 36 Yogoslav wheat cultivars were separated by SDS-PAGE to identify their alleles, and the frequency of each allele was calculated. Eleven alleles from the three Glu-loci were recognized, three at the Glu-A1 locus, six at the Glu-B1 locus and two at the Glu-D1 locus. The most frequent allele was a (55.5%) from Glu-D1, which controls synthesis of subunits 2+12. The Glu-1 quality score varied from 4 (KG-III/27, KG-75, Morava and KG-101/7) to 10 (Lepenica). The mean Glu-1 quality score of cultivars and lines from Kragujevac was 6.8, for cultivars from Zagreb 7.2, and for cultivars from Novi Sad was 7.9. Most of the genotypes with a quality score of 8 or above, had high sedimentation values (Zeleny test). There were no significant differences in allelic composition at the Glu-1 loci among wheat genotypes from Kragujevac, Novi Sad and Zagreb.     

CIMMYT新型人工合成小麦Pina和Pinb基因等位变异

六倍体人工合成小麦由硬粒小麦（Triticum turgidum subsp. durum）与粗山羊草（Aegilops tauschii Coss.）杂交产生,是研究小麦进化过程中基因变异的重要材料。以国际玉米小麦改良中心（CIMMYT）提供的57份由野生二粒小麦（T. turgidum subsp. dicoccoides）与粗山羊草杂交产生的新型人工合成六倍体小麦为材料，用单籽粒特性测定仪和Pina、Pinb特异性PCR引物对其籽粒硬度变异以及控制籽粒硬度的主效基因Pina和Pinb的分布情况进行了研究。结果表明，这些材料的SKCS硬度值变异较大，从10.5到42.6，其中15~30的占78%。共有Pina-D1a、Pina-D1c、Pinb-D1h和Pinb-D1j 4种等位变异型，基因型为Pina-D1a/Pinb-D1j的8个，占14%；基因型为Pina-D1c/Pinb-D1h的49个，占86%。方差分析表明，基因型Pina-D1a/Pinb-D1j与Pina-D1c/Pinb-D1h对籽粒硬度的影响差异不显著，但父本粗山羊草和母本野生二粒小麦以及二者间的互作对籽粒硬度有显著影响，说明除Pina和Pinb外，还有其他微效基因影响籽粒硬度的形成。     

Stylar ribonucleases in almond: correlation with and prediction of incompatibility genotypes

To clarify incompatibility relationships among almond cultivars, 35 were analysed for stylar ribonucleases, which have previously been shown to correlate with incompatibility S alleles. Stylar proteins were extracted and separated electrophoretically and the zymograms compared with ladders of ribonucleases corresponding to the 12 S alleles previously reported. Sixteen cultivars showed a band corresponding to two of the known ribonucleases, 17 showed one known ribonuclease and one ‘new’ band, and two showed two new bands. Twelve new ribonucleases were detected; 11 were attributed to new S alleles (S₁₃ to S23) and a mutant form of S₇ was attributed to S_7A. Genotypes were proposed for nine cultivars of five incompatibility groups that had not been genotyped previously, VII, X, XI, XII and XIII. Twenty‐four cultivars of unknown incompatibility relationships were provisionally genotyped: six of these could be assigned to existing groups and two new groups were established, XIV and XV, along with group O of cultivars with unique genotypes. Test crosses confirmed that eight pairs of cultivars showing similar zymograms were indeed cross‐incompatible, including the two representatives of each of the two new groups. Virtually all self‐incompatible cultivars of known genotype are listed in a table. The data should be useful for planning cultivar combinations for orchards and for designing crosses for breeding programmes.     

Powdery-mildew-resistance genes Mla29 and Mla32 in H. spontaneum derived winter-barley lines

Allelism to the highly polymorphic Mia locus was demonstrated for the powdery-mildew resistance of two Hordeum spontaneum derived winter–barley lines, ‘110-4 × Sonja’ and ‘142–29 × Dura’, by testing the F2 progeny of crosses between these lines and the winter-barley cv. ‘Triton’ (Mlal3) with two appropriate isolates. The results were confirmed by RFLP analysis, using the probe MWG 1H036, which is very closely linked to the Mia locus. The designations Mla29 and Mla32 are proposed for the genes identified in the two lines.     

Association analysis of Puroindoline-D1 and Puroindoline b-2 loci with 13 quality traits in European winter wheat (Triticum aestivum L.)

Grain hardness, a major determinant influencing end-use quality of common wheat, is mainly controlled by Puroindoline a-D1 (Pina-D1) and Puroindoline b-D1 (Pinb-D1) genes. Recently, additional puroindoline genes, designated Puroindoline b-2 (Pinb-2), were described. This study examined frequencies of Pin-D1 alleles and Pinb-2 variants in 94 West European wheat genotypes and assessed their association with 13 quality traits considering population and family structure. The survey was completed by analyzing the Grain softness protein-1 gene. Results indicated sequence variation only for Pinb-D1 and Pinb-B2 genes. Pinb-D1b was the predominant hard allele. Pinb-B2v3-1 was the most common Pinb-2 variant, followed by a newly discovered variant Pinb-B2v3-5. Association mapping carried out in the whole sample population showed that Pinb-D1 alleles were associated with 11 quality traits, whereas Pinb-B2 variants were only associated with semolina extraction. Considering only the panel of hard wheat genotypes, variation for flour ash content, sedimentation value, gluten index and loaf volume was found to be associated with Pinb-D1 mutations suggesting that different Pinb-D1 mutations might have particular effects on quality traits. Our study indicated that Pinb-D1d was associated with inferior sedimentation value, gluten index and loaf volume, for which reason this mutation should be disregarded in breeding for quality wheat.