利用分子标记辅助选择育种(MAS)技术改良水稻恢复系粤恢826

[目的]改良杂交稻恢复系粤恢826,以提高其稻瘟病和白叶枯病抗性,改良米质,为选育抗病、优质的杂交稻组合提供良好亲本材料.[方法]以含稻瘟病抗性基因Pi1和Pi2、白叶枯病抗病基因Xa23及蜡质基因Wx的中间材料Z1103为供体亲本,杂交水稻强恢复系粤恢826为受体亲本,利用分子标记辅助选择(MAS)技术和系谱选育方法,聚合4个外源基因以改良粤恢826的抗病性和米质,并进行稻瘟病和白叶枯病抗性及米质鉴定.[结果]经SSR分子标记检测、田间抗病性及米质鉴定,获得以粤恢826为遗传背景且含有目标基因的6个改良株系,通过农艺性状筛选与恢复力测试,优选到一个含有Pi1、Xa23和Wx基因的纯合株系,其恢复力好,农艺性状优良,2014年早造定名为粤恢88,其田间鉴定稻瘟病抗性3级,白叶枯病抗性1级,米质为软米.2014年晚造与两系不育系Y58S配制杂交稻组合Y两优88,其在品比试验中产量达6543 kg/ha,比对照深两优58香油占增产4.97%,未达显著水平(P>0.05),且抗稻瘟病,中抗白叶枯病,米质鉴定为国优3级和省优3级.[结论]MAS技术可有效聚合多基因(Pi1、Xa23和Wx基因),使粤恢826的稻瘟病和白叶枯病抗性及米质明显改良,获得抗稻瘟病、高抗白叶枯病、米质为软米的新恢复系粤恢88,为选育抗病优质的杂交稻组合提供良好亲本材料.     

Nitrogen mineralization from digestate in comparison to sewage sludge,compost and urea in a laboratory incubated soil experiment

This paper evaluated, in a laboratory incubated soil, the properties of digestate as a nitrogen fertilizer in comparison with sewage sludge, compost and urea, this last as a typical mineral fertilizer. The incubation period lasted for 90 d and during this time, pH, CO₂ and evolution were measured. The maximum concentration of nitrate was reached in the incubated microcosm fertilized by urea (133 mg kg⁻¹ after 62 d), and that of digestate was very similar (113 mg kg⁻¹). Soil treated with compost showed a slower nitrate evolution. A significantly negative correlation was detected between cumulative nitrogen nitrified at the end of the trial, and the values of the C:N ratio of the biomasses used (compost, sludge and digestate) (mg kg⁻¹ vs . C:N, r = –0.94, n = 3, p < 0.05), and between the alkyl‐C content at the end of the experiment (mg kg⁻¹ vs . alkyl‐C, r = –0.95, n = 3, p < 0.05). As expected, pH decreases and soil respiration (CO₂ evolution) were also well correlated with the content of nitrate. Considering that about 90% of the nitrogen content in the digestate is short acting, the results obtained indicate that the nitrogen rate of mineralization in digestate is very similar to that of urea, confirming that digestate could replace traditional mineral fertilizers.     

奶牛MHC及其免疫学研究进展

奶牛MHC又称白细胞抗原,它不仅与移植排斥反应有关,而且广泛参与免疫反应的应答和调节。阐述了MHC的基因结构、MHC的免疫作用、MHC与疾病的关系以及在MAS中如何对实验材料和统计方法进行选择、怎样对待复杂病因疾病与MHC的关系等,最后展望了MHC作为动物抗病力的一种遗传标记的应用前景。     

A practical guide to solid-state NMR of half-integer quadrupolar nuclei with some applications to disordered systems

The practical aspects for obtaining useful NMR spectra of half-integer quadrupolar nuclei in diamagnetic solids are discussed in some detail. The general appearance of the Magic-Angle Spinning (MAS) line shape is described. The effects of a distribution in isotropic chemical shift and quadrupole interaction on the MAS line shape is shown. The necessity of fast MAS and short excitation pulses is demonstrated. The possibilities of ²⁷Al MAS NMR at high fields is shown for some clay minerals. Techniques to obtain spectra free of quadrupolar broadening, such as DOuble Rotation (DOR), Dynamic Angle Spinning WAS) and Multiple-Quantum Magic-Angle Spinning (MQMAS), are discussed with some emphasis on the newly developed MQMAS method. The latter is used to describe structural details of phosphorus-impregnated alumina and aluminosilicate sol-gel materials. These examples give a good indication of the capabilities of this new technique.     

Marker-assisted selection for forelimb-girdle muscular anomaly of Japanese Black cattle

Forelimb‐girdle muscular anomaly is a hereditary disorder of Japanese Black cattle characterized by tremors and astasia caused by hypoplasia of the forelimb‐girdle muscles. The locus responsible for this disorder has been mapped on a middle region of bovine chromosome 26. In this study, we applied marker‐assisted selection to identify the carriers of this disorder. Four microsatellite markers, DIK4440, BM4505, MOK2602 and IDVGA‐59, linked to the disorder locus were genotyped in 37 unaffected offspring of a carrier sire. Transmission of the mutant or wild‐type allele of the disorder locus of the sire to the 37 offspring was determined by examining the haplotypes of these markers. The results showed that nine and 18 of the 37 animals possessed the paternally transmitted mutant and wild‐type alleles, respectively, and therefore, the nine animals with the mutant allele were identified as carriers. We concluded that the marker‐assisted selection using these four markers can be applied for the identification of the carriers of forelimb‐girdle muscular anomaly of Japanese Black cattle.     

聚合抗褐飞虱基因bph20（t）和bph21（t）及抗稻瘟病基因Pi9水稻株系筛选

【目的】筛选聚合抗褐飞虱和抗稻瘟病基因水稻材料,为培育新型抗褐飞虱兼抗稻瘟病的水稻新种质提供参考。【方法】利用常规育种、分子标记辅助育种和抗病虫鉴定相结合的手段,将抗稻褐飞虱基因bph20（t）和bph21（t）以及广谱高抗稻瘟病基因Pi9聚合到优良保持系博ⅢB的遗传背景中。【结果】bph20（t）的分子标记RM540和BYL7、bph21（t）的分子标记RM5348和RM222未在稻褐飞虱抗、感亲本间扩增出特异条带,无明显的多态性,不能用于该育种群体抗褐飞虱基因bph20（t）和bph21（t）的检测。Pi9的显性分子标记pB8以及共显性分子标记PB9-1在稻瘟病抗、感亲本之间可扩增获得特异条带,具有多态性,可用于Pi9基因的检测。经抗虫鉴定并利用标记PB9-1对BC6F2群体的22株材料进行PCR扩增,含有Pi9基因杂合体的有10株,纯合体有6株,不含Pi9基因的有7株。用源自广西南宁田间感褐飞虱和稻瘟病菌株进行多次抗病虫鉴定,筛选获得一批抗褐飞虱材料,其中抗性与抗虫亲本BPH54相当的材料有6份,在这6份材料中含有Pi9基因且抗稻瘟病的材料有5份,对稻褐飞虱的抗性与供体亲本BPH54水平相当。【结论】通过常规育种、分子检测和抗虫鉴定相结合的办法,筛选获得5份聚合褐飞虱抗性基因（bph20和bph21）和抗稻瘟病基因Pi9的抗或高抗水稻中间材料,为选育新的双抗保持系和不育系提供种质材料。     

野生稻增产QTL导入9311之近等基因系的构建

以超级杂交中稻恢复系9311为受体和轮回亲本,马来西亚普通野生稻(O.rufipogon)为增产QTL yld1.1和yld2.1的供体进行杂交和连续回交,各世代采用分子标记辅助选择,至BC6F1后自交,得到BC6F2群体,通过分子标记检测,获得分别携带野生稻增产QTL yld1.1、yld2.1及同时携带yld1.1和yld2.1的3套近等基因系.对同时携带yld1.1和yld2.1的近等基因系进行遗传背景分析,发现其与受体9311的遗传组成有93.9%一致.田间试验表明,野生稻增产QTL近等基因系的产量均高于受体,说明将野生稻增产QTL转移至杂交稻恢复系中,能提高其产量水平,且2个QTL的增产效果大于单个QTL的效果.     

玉米免DNA制备单株SSR和SCAR基因分型方法研究

探讨采用免DNA制备法分析玉米单株SSR与SCAR分子标记的基因型.分别刮取各单株少许叶肉细胞到1×PCR缓冲液中,置于PCR仪上95℃10 min,冷却,添加PCR其它组份,完成SSR与SCAR的PCR扩增与显色成像.免除模板DNA制备过程,对掖478与丹340两个亲本及57个(共58个)F2分离群体单株分别实现SSR标记-phi402893基因型快速鉴定,对掖478与丹340两个亲本及5个F2分离群体单株分别实现SCAR标记-MITE185基因型快速鉴定.     

基于MAS的农机制造业信息集成系统设计

针对我国农机企业特点,将多Agent系统引入到农机制造环境中,研究了Agent和多Agent系统(MAS)的定义及特性,设计了一种基于MAS的农机制造业信息集成系统,并对系统运行过程进行了详细分析,认为该系统的设计实现,对于整合农机制造企业生产能力,从而提高农机企业的市场竞争力具有一定的理论意义和实际应用价值。     

基于MAGIC群体的水稻镉含量全基因组关联分析

【目的】基于水稻MAGIC-Hei(Multi-parent advanced generation inter-cross)群体,在多环境下挖掘镉含量相关新位点/基因,并筛选含有低镉等位基因的优良株系,为选育低镉积累品种提供新的基因和种质资源。【方法】将由8个亲本衍生的MAGIC群体分别于2017、2018、2019和2020年度种植于湖南长沙并开展稻米镉含量表型测试分析。利用GBS(genotyping by sequencing)简化基因组测序获得基因型数据,对稻米镉含量开展全基因组关联分析(genome-wide association analysis,GWAS),发掘QTL位点,解析其遗传机制。【结果】检测到了14个镉积累相关的QTL位点,除了第8染色体之外,其他11条染色体上均有分布。其中6个位点与已报道基因一致,8个为新发现位点。另外,这8个位点分布在第2、4、7、9和12染色体上,均可以在两个及以上环境中检测到,效应较为稳定,可用于下一步精细定位及功能研究。结合基因注释和基因表达分析结果,推测LOC_Os02g37160、LOC_Os02g49560、LOC_Os04g39010和LOC_Os06g46310为镉含量相关位点候选基因,这些基因与重金属转运和积累等功能相关。另外,我们筛选到10个携带有利等位基因的优良株系,可用于低镉积累水稻材料的创制。【结论】发掘了8个水稻镉积累相关性状的QTL位点和低镉优异材料,对于镉积累相关遗传研究和利用分子标记辅助选育低镉积累品种具有一定意义。