玉米株高QTL的定位及主效QTL的确认

为了探索玉米株高的遗传机制,定位玉米株高的数量性状位点(QTL),本研究以玉米自交系PH4CV为轮回亲本,以郑58为供体亲本,构建BC₁F_3:4分离群体,在4个环境下对该群体进行玉米株高表型鉴定。表型分析结果表明,基因型之间差异极显著,且不同环境之间的株高相关性极显著,说明不同环境之间的株高变异具有共同的遗传基础。利用包含5.5万个单核苷酸多态性标记(SNPs)的基因芯片进行基因型鉴定,并结合基因型和表型数据进行全基因组关联分析。在错误发现率(FDR)为0.05时,检测到10个显著性SNPs,这些显著性SNPs主要位于第2号染色体上,-log₁₀(P)值最大的标记为Chr2_194690794。利用线性回归模型对显著SNPs进行表型贡献率及效应分析,发现位于第2号染色体的标记Chr2_194690794效应值最大,贡献率最高,来源于PH4CV的基因型的正效应。利用BC₁F_5:6群体进行基因型和表型鉴定,进一步确认了标记Chr2_194690794与株高QTL的连锁关系,表明在第2号染色体上存在1个控制株高的QTL。本研究为玉米株高QTL的精细定位奠定了基础。     

基于BSA和SLAF-Seq技术对大豆主茎节数QTL精细定位

为了加速大豆主茎节数候选基因的的克隆和功能验证,并为大豆主茎节数分子标记辅助育种提供分子基础,本研究通过高通量测序检测与大豆主茎节数相关数量性状区间(QTL),结合双亲重测序信息开发QTL区间InDel分子标记,实现了大豆主茎节数相关主效QTL区间的精细定位。本研究以少主茎节数C025材料为母本,多主茎节数中119为父本杂交衍生的重组自交系(RIL)102个株系为试验材料,取自交系中极端少主茎节数30株和极端多主茎节数30株,构建两个极端混池,利用传统分群分析法(BSA)和全基因组特异性位点扩增片段测序手段(SLAF-Seq)相结合的方法在4号染色体检测到与大豆主茎节数相关的5个QTL。为了进一步缩小QTL区间,依据双亲材料的高通量重测序信息,获取QTL区间的插入缺失位点(InDel)信息,并开发InDel标记。首先利用InDel标记在F₂群体进行基因型分析,结果主效位点落在第3个QTL区间。其次在主效区间开发8个共显性InDel标记,结合RIL群体全部株系进行表型鉴定,最终获得9个交换单株,将主效区间分为6种交换类型,结合表型分析最终将大豆主茎节数位点精细定位到InDel标记Chr04-38和Chr04-46之间,其区间只有171.9 kb,包含候选基因6个,实现了大豆主茎节数的精细定位。本研究通过高通量测序与极端混池相结合的方法可以高效快速地检测与大豆主茎节数相关区间,并结合双亲重测序信息开发关联区间InDel分子标记,精细定位大豆主茎节数。本研究开发的Indel标记Chr04-38和Chr04-46与大豆主茎节数紧密连锁,有利于后期大豆主茎节数分子标记辅助育种。     

绵羊X染色体59194976位点多态分析及其与尾（臀）脂性状相关性研究

尾脂沉积能力在脂尾型绵羊和瘦尾型绵羊问存在很大的差异,但其沉积脂肪的遗传特性与分子机制仍不明晰。为此,本研究选择尾型极端差异的阿勒泰羊（巨型脂臀）、湖羊（短脂尾）和黑萨福克羊（长瘦尾）,采用PCR-RFLP方法检测绵羊X染色体59194976位点多态性,分析其与尾（臀）脂沉积能力的相关性。结果表明：在阿勒泰羊群体中G等位基因属优势等位基因,其两等位基因比值（G／A）分别是湖羊和黑萨福克羊的6倍和68倍,且G等位基因在阿勒泰羊中趋于纯合。卡方检验结果表明,阿勒泰羊在该位点均处于Hardy-Weinberg平衡状态（p〉0．05）,而湖羊和黑萨福克羊在该位点均处于Hardy-Weinberg极不平衡状态（p〈0．01）。以上结果提示,绵羊x染色体59194976位点SNP可作为理想的分子标记应用于高、低脂绵羊品种选育。     

Genetic relationships among improved varieties of rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) in Indonesia over the last 60 years as revealed by morphological traits and DNA markers

Morphological traits and two kinds of molecular markers were employed to study the genetic relationships among improved rice (Oryza sativa ) varieties of Indonesia since 1943. Dendrograms based on morphological traits and both molecular markers (simple sequence repeats, SSR and single nucleotide polymorphism, SNP) agreed in separating the varieties into two primary groups. Based on the morphological traits, a larger group (>60 %) contains varieties with smaller sizes compared with those in the smaller group (<40 %). SSR and SNP markers revealed that most of the varieties belonged to indica (88; 89 %) and japonica (9; 8 %) subspecies, and 3 % of varieties were not involved in two subspecies. The molecular markers revealed that the genetic diversity (H) stagnated between stage II (1967–1985) and stage III (1986–2003). However, during stage I (1943–1966), H was higher than in the other stages as revealed by SNP markers, while H in stage I was lower than in the other stages as revealed by SSR markers. In this study, the two molecular data sets were positively correlated and positive correlations between the phenotypic and molecular data depended on the kind of molecular marker: SNP had higher Mantel r values than SSRs. Besides, SSR markers seem to be appropriate for pedigree studies, while SNP markers could be used to reveal genomic relationships. These findings were attributable to the different properties of these two different markers. These results suggested that the diversity and differentiation of both the phenotypic and molecular marker variations were probably resulted from the crossing and selection in rice breeding in Indonesia. We suggest that Indonesia needs another strategy to improve new varieties to avoid a reduction in genetic diversity and similarity.     

Diversity and differentiation of <Emphasis Type="Italic">Oryza sativa</Emphasis> and <Emphasis Type="Italic">O. rufipogon</Emphasis> in Indonesia

Analysis of the genetic structure of Indonesian Oryza sativa and O. rufipogon using neighbour-joining trees based on single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers revealed that O. sativa in Indonesia is separated from O. rufipogon. Accessions of O. sativa in this study were differentiated into two major groups, indica and tropical japonica, excluding some varieties. SSR and SNP markers revealed the high value of differentiation (F _ST) and genetic distance (D) between indica and tropical japonica and we discovered four loci by SNP markers and one locus by SSR markers that play a role in differentiation between indica and tropical japonica. Interestingly, genetic diversity (H) in O. rufipogon was lower than that in O. sativa, however H in O. rufipogon was the highest and H in tropical japonica was the lowest when O. sativa was divided into two groups. Inbreeding coefficient (Fst) showed evidences that gene flow (Nm) between species and within species might be one of the mechanisms related to the diversification and differentiation of Indonesian rice germplasm by asymmetric pattern between species and within O. sativa as revealed by SSR and SNP markers. In addition, we found evidences on stabilizing selection in Indonesian rice germplasm and they might be the reasons why Indonesian rice germplasm did not differentiate due to source location of landrace. However, we found a weak relation between SSR and SNP markers probably due to highly polymorphic in SSR and the different properties of both markers.     

小麦产量及氮效率相关性状的全基因组关联分析

  【目的】  探明控制产量及氮效率相关性状的稳定基因关联位点,为高产和氮素高效小麦育种及养分管理提供参考。  【方法】  采用134个小麦品种 (系) 为试验材料,依据小麦产量水平600和400 kg/hm2的需氮量设置正常氮 (T1) 和低氮 (T2) 2个处理,进行了2年田间试验,共形成4个处理环境。对小麦成熟期与产量及氮效率相关的14个性状进行了表型鉴定,采用GLM + Q一般线性模型和MLM + K + Q混合线性模型相结合的方法,利用群体差异SNP分子标记 (90K SNP芯片) 对小麦产量和氮效率相关性状进行全基因组关联分析。  【结果】  与正常氮处理相比,低氮处理条件下小麦籽粒产量、秸秆产量显著下降;所有性状的遗传力均在75%以上,其中小穗数的遗传力最高 (95.12%)。利用9329个SNP标记进行关联分析,共检测到382个SNP标记位点与供试14个性状存在显著关联（P ≤ 0.001）,分布在21条染色体上。有305个 (79.84%) SNP标记位点仅在一个关联分析环境中被检测到;有77个位点在至少两种处理环境 (包含平均值环境) 中被检测到与同一性状显著关联 (稳定关联标记)。其中9个SNP标记位点在至少3个环境中被检测到。在4个环境下 (包括平均值环境) 均检测到的稳定关联位点有4个:BobWhite_c47168 _598、Kukri_c31599_1456、wsnp_CAP11_c1761_958064和Excalibur_c62826_254,分别与穗粒数、籽粒氮含量和小穗数显著关联;同时与至少3个性状显著关联的SNP标记位点共12个,分别位于2A、3A、4A、5B和7B染色体上,贡献率为11.14%～22.97%,其中,标记BobWhite_c47168_598和Kukri_c31599_1456还分别定位了两个多环境 (4种环境) 稳定位点。根据12个与多性状共同定位位点和4个多环境 (4个环境) 稳定位点关联的SNP标记位置获得稳定位点附近区域的基因 (基于LD block等方式估算的区间大小),使用NCBI中CDD工具和EnsemblPlants网站对这些基因进行基因功能注释,根据功能注释,共得到10个与产量和氮效率性状相关的候选基因。  【结论】  氮供应水平对小麦成熟期产量和氮效率相关性状均有显著影响,氮素累积量与小麦产量显著正相关。本试验中检测到的与产量及氮效率相关性状显著关联的位点中,79.84%的SNP标记位点仅在一个氮处理环境中出现,环境稳定性较差;4个位点在4个环境条件下均被检测到,环境稳定性较好;12个SNP标记位点同时与至少3个性状显著关联,涉及性状均为产量及氮效率相关性状,反映了籽粒产量与氮素效率之间的显著相关关系,也可能是同时控制这些性状的遗传热点位点。根据这些热点位点和环境稳定性好的位点筛选到10个与产量及氮效率相关性状有关候选基因,值得深入探讨。     

水稻光叶性状基因gl1的精细定位与候选基因分析

光叶水稻是一类在叶片和谷粒等表面都光滑无毛的水稻,是美国南部和非洲一些国家的主栽品种。已有研究表明水稻的光叶性状受一对位于第5染色体上的隐性基因gl1控制。本试验旨在对gl1进行精细定位,分析候选基因,为最终克隆gl1基因、研究毛状体形态建成的调控奠定基础。首先根据与gl1连锁的RFLP标记在第5染色体上的大致位置,有...     

Detection of genetic integrity of conserved maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) germplasm in genebanks using SNP markers

Twenty maize landrace accessions regenerated and conserved in five maize genebanks were investigated for genetic integrity using 1,150 Single Nucleotide Polymorphisms (SNPs) and 235 SNP haplotypes. The genetic diversity of three accessions changed significantly in terms of the average number of alleles per locus. Ten out of twenty accessions had significantly different SNP allelic frequencies, either after regeneration or in the same accession held in different genebanks. The proportion of loci with significant changes in SNP allelic frequency was very low (37/1,150). Changes in the major allelic frequency (MAF) for the majority of SNP loci (60.2–75.2%) were less than 0.05. For SNP haplotypes, the genetic diversity of four accessions changed significantly in terms of average number of haplotype alleles and polymorphic information content (PIC) per locus. The proportion of SNP haplotype alleles lost in the later generations ranged between 0 and 22.6%, and at the same time 0–19.9% of the SNP haplotype alleles appeared in later generations, however, these were absent in the earlier generations. Dynamic changes in genetic integrity, in terms of presence and absence of genes (alleles), by both SNP and SNP haplotype analysis were detected during regeneration. A suboptimum number of ears harvested in one generation can be combined with those from another, repeated regeneration to capture the diversity of the previous generation. Use of molecular markers during regeneration of accessions can help in understanding the extent of genetic integrity of the maize accessions in ex situ genebanks and in recommending the best practice for maintaining the original genetic diversity of the genebank accessions.     

草鱼羧肽酶A1基因(CPA1)部分片段的单核苷酸多态性(SNP)多态性及其与生长性状的关联分析

羧肽酶A (EC 3.4.16)是一类水解蛋白和多肽底物C端芳香族氨基酸或脂肪族氨基酸残基的消化酶.在草鱼生长相关的功能基因上研究单核苷酸多态性(SNP)与生长的相关性可为草鱼的分子辅助育种提供依据.本研究根据草鱼(Ctenopharyngodon idella)EST-SNP库的羧肽酶A1基因(CPA1)重叠群的2个Contig扩增该基因的序列片段,采用直接测序法,经过序列比对,共筛到2个颠换SNP位点:C+412A和A36C,分别位于CPA 1基因外显子5的34bp和内含子3的36 bp处,前者为错义突变.然后用一个群体的296尾草鱼对这2个位点用SnaPshot的方法进行检测和分型,统计基因型频率:A36C位点的AA基因型占26.7％,AC基因型占52.0％,CC基因型占21.3％.C+412A位点的AA基因型占15.5％,AC基因型占40.5％,CC基因型占43.9％.利用一般线性模型分析2个SNP位点与草鱼体质量、体长等重要生长性状的关系.关联分析结果显示,C+36A位点不同基因型在体质量、眼间距均值上存在显著差异(P＜0.05).并且AA基因型和CC基因型在体质量、体长、体宽和眼间距上存在显著差异(P＜0.05).AA基因型各项指标均值显著高于CC基因型.C+412A位点在体质量等生长性状上差异不显著(P＞0.05),该位点和生长不相关,但是CC基因型和AC基因型在体重和肛前距上差异显著(P＜0.05),该位点CC基因型的6个生长性状均值都高于AA基因型.由两个位点组成的5种双倍型在体质量上存在显著差异(P＜0.05).双倍型D3和D5在体质量上存在差异显著(P＜0.05).双倍型D3和D8在体质量、体宽、体长、体长/头长等生长性状上都存在显著差异(P＜0.05).D3的各项指标均值最高,D8的各项指标均值最低.本研究结果显示,可以考虑将草鱼CPA1基因作为候选基因,用于草鱼的分子辅助育种.     

Allelic diversity of a beer haze active protein gene in cultivated and Tibetan wild barley and development of allelic specific markers

The formation of haze is a serious quality problem in beer production. It has been shown that the use of silica elute (SE)-ve malt (absence of molecular weight (MW) ～14000 Da) for brewing can improve haze stability in the resultant beer, and the protein was identified as a barley trypsin inhibitor of the chloroform/methanol type (BTI-CMe). The objectives of this study were to determine (1) the allelic diversity of the gene controlling BTI-CMe in cultivated and Tibetan wild barley and (2) allele-specific (AS) markers for screening SE protein type. A survey of 172 Tibetan annual wild barley accessions and 71 cultivated barley genotypes was conducted, and 104 wild accessions and 35 cultivated genotypes were identified as SE+ve and 68 wild accessions and 36 cultivated genotypes as SE-ve. The allelic diversity of the gene controlling BTI-CMe was investigated by cloning, alignment, and association analysis. It was found that there were significant differences between the SE+ve and SE-ve types in single-nucleotide polymorphisms at 234 (SNP(234)), SNP(313), and SNP(385.) Furthermore, two sets of AS markers were developed to screen SE protein type based on SNP(313). AS-PCR had results very similar to those obtained by immunoblot method. Mapping analysis showed that the gene controlling the MW～14 kDa band was located on the short arm of chromosome 3H, at the position of marker BPB-0527 (33.302 cM) in the Franklin/Yerong DH population.     

The 18S rDNA gene discriminates between red-listed and unexplored ethnomedicinal species of Myristicaceae restricted to humid tropics of India

A potentially diagnostic 18S rDNA (ribosomal DNA) gene was amplified reliably from red-listed ethnomedicinal species of Myristica and its wild and related genera. Individuals from nine species of Myristicaceae were utilized for the study. The sequences ranged from 1,767 to 1,794 nucleotide (nt) in length. The GC content (%) varied from 52.77 to 51.04. The frequencies (%) of nt were A (23.31), T (23.82), C (24.48) and G (28.39). The alignment of all sequences produced 195/1,516 variable sites and 1,257/1,516 conserved sites. Total numbers of single nucleotide polymorphism (SNP) sites found in the alignment were 146/1,516. Knema andamanica (Warb.) W.J. de Wilde was the most distinct that included 18 variable regions and 15 InDel with 27 SNP sites, specific to this species. The identified regions from nine species of Myristica and its wild and closely related genera were deposited in the GenBank Database (Accession numbers JN228257-JN228265). Comparison of morphological identifications and phylogenetic analysis indicated that the specimens were correctly assigned on the basis of a short stretch of 18S rDNA (~1,600 bp) making this a potentially useful marker for the rapid molecular assignment of an unknown related species also. Significant sequence homology ranging from 72 to 99 % was observed on comparison with 18S rDNA genes of other plants in the public domain. A comparison of intraspecific data information of nine 18S with that of 73 matK and 86 rbcL sequences from GenBank revealed that polymorphism, divergence and conservation is higher in 18S locus for Myristicaceae. Hence these markers may be utilized for phylogenetic analysis, evaluation of species richness during ecological surveys or for environmental assessments. These molecular markers are especially important due to the fact that the species studied are mostly vulnerable and red-listed with limited availability in endangered ecological niches.     

基于简化基因组测序技术的甘薯HRM分子标记开发及其应用

目前甘薯中针对SNP位点的分子标记开发及应用的报道较少。为开发甘薯特异SNP分子标记,本研究利用简化基因组测序技术对甘薯种质材料进行测序,筛选稳定的SNP位点,将其开发为基于HRM技术的分子标记,并在甘薯种质材料中进行验证。通过对23个甘薯种质材料简化基因组测序数据的分析,共发现835 756个SNP多态性位点,筛选其中的3 650个含有SNP多态性位点的高质量测序片段,成功设计了134对引物;初步验证发现,22对(16.42%)引物没有扩增产物,15对(11.19%)引物扩增产物2个以上,36对(26.87%)引物的扩增产物没有差异。61对(45.52%)引物在8个样本中的扩增特异性好,而且样本之间有差异。最后筛选34对扩增多态性丰富的引物对52份甘薯种质材料进行扫描,发现材料间多态性介于27.27%~90.91%之间,平均多态性达到59.35%。聚类分析表明,参试52份甘薯种质材料之间的差异较小,多数材料与骨干亲本南瑞苕、徐薯18之间关系较近,国外引进甘薯材料和地方品种差异较大。建议在今后甘薯育种中尽量选用地方品种和国外甘薯品种,从而更好地拓宽甘薯遗传背景。本研究初步建立了基于简化基因组技术和HRM技术开发甘薯SNP分子标记的新思路,为今后甘薯SNP分子标记开发提供了参考。同时本研究开发的甘薯分子标记,丰富了甘薯分子标记类型,为甘薯研究者开展快速的分子标记研究提供了支持。     

鹅HMGR基因内含子5的SNP及其与鹅重要经济性状的关联分析

本文屠宰测定了116只皖西白鹅胴体性状、羽绒性状和肉质性状，克隆了鹅3－羟基－3－甲基戊二酸单酰辅酶A还原酶（HMGR）基因内含子5，采用PCR-SSCP检测其SNP，并分析了SNP与鹅重要经济性状之间的关联性。结果显示，鹅HMGR基因内含子5长704bp，与鸡的同源性44.0%；PCR-SSCP检测发现，内含子5存在一对等位基因A和B，A和B的基因频率分别为0.7716和0.2284。分析SNP基因型与鹅重要经济性状的关联性，结果表明，AA型可以显著提高鹅的胸肌重和腺胃重（P<0.05），增加千朵重（P<0.01），和降低绒系水率（P<0.05）；AB型则具有显著降低胸肌纤维直径（P<0.01）和提高胸肌45pH的作用（P<0.05）。     

贵州本地山羊STAT5A基因多态性及其与生长性状关联分析

本研究通过探讨STAT5A基因SNP与山羊生长性状关联性,旨在为山羊选种选育提供更好的科学依据。实验以贵州白山羊和贵州黑山羊为研究对象,采用DNA池法及PCR-SSCP技术检测STAT5A基因单核苷酸多态性。结果发现,在贵州白山羊和贵州黑山羊STAT5A基因内含子10均检测到1个SNP位点G127A,表现为3种基因型,分别命名为GG、GA和AA。基因型与生长性状关联分析显示,贵州黑山羊基因型GA个体的胸围和体重指标显著高于基因型GG个体（p〈0.05）,而其余3个指标均差异不显著（p〉0.05）;贵州白山羊基因型GA个体的体斜长、胸围和管围指标显著高于基因型GG个体（p〈0.05）,而其余指标均差异不显著（p〉0.05）。研究结果提示：STAT5A基因可能是影响山羊体重、体斜长、管围和胸围的主效基因或与主效基因连锁,G127A位点可望作为提高山羊个体生长性状的分子遗传标记。     

水稻橙红色突变体的遗传分析与基因定位

从水稻材料H9808航天诱变的后代中筛选出1株与色素相关的突变体,该突变植株在幼穗分化期新出幼叶的叶脉为橙红色,到拔节后期植株节间及下部约1/3的茎秆均呈现橙红色,在茎杆节底部中心有一橙红色的原点,抽穗时颖壳为橙红色,并保持到种子成熟,遗传分析表明突变体受1对隐性基因控制。在突变体与9311杂交的F2代隐性群体中,利用SSR标记将橙红色基因定位在2号染色体RM5350和RM12601标记之间,遗传距离分别为0.55cM和1.38cM。再利用新设计的InDel标记,进一步将该基因定位在S1和S2之间,遗传距离分别为0.41和0.25,为克隆水稻橙红色基因奠定了基础。     

西安地区荷斯坦奶牛群5个基因位点遗传多态性与泌乳性状的相关分析

首次以IGFBP-3基因作为中国荷斯坦牛泌乳性状的候选基因，对中国荷斯坦奶牛群5个基因位点中4个多态基因位点与泌乳性状进行了相关分析。κ-cn、β-lg、β-lg 5′侧翼区和IGFBP-3多态基因位点基因型与泌乳性状的最小二乘分析和多重比较表明，κ-cn基因位点基因型对所有的性状影响不显著；IGFBP-3 BB型的305 d泌乳量显著高出AA、AB型1054.17 kg和838.15 kg (P <0.05)， AB型的乳蛋白率显著高于BB型(P< 0.05)；β-lg AA型对乳脂率与乳蛋白率的比值有正效应，AB型对乳蛋白率具有负效应；β-lg 5′侧翼区AA型的305 d泌乳量显著高于AB型(P <0.05)，AA型的乳脂率显著高于BB型(P < 0.05)， BB型的乳蛋白率显著高于AB型(P <0.05)。     

Investigation of the genetic structure of some common bean (Phaseolus vulgaris L.) commercial varieties and genotypes used as a genitor with SSR and SNP markers

Common bean is a species belonging to the Phaseolus genus of the Leguminosae family. It has economic importance due to being rich in protein, vitamin A and C, and minerals. Being one of the most cultivated species of legumes, the determination of genetic diversity in bean genotypes or populations has an important role in terms of our genetic resources. The objective of this study was to evaluate the genetic structure of 94 genotypes which were cultivated in different parts of the world and our country with SSR and SNP markers. 10 SSR loci and 73 SNP primers were used for the determination of genetic structure in commercial cultivars and breeding lines. All of the SSR and SNP loci used in the study were found to be polymorphic. A total of 89 alleles were identified for 10 SSR loci. Mean number of alleles per locus (Na?=?8.9), effective allele number (Ne?=?3.731), Shannon information index (I?=?1.468), observed heterozygosity (Ho?=?0.023), and expected heterozygosity (He?=?0.654) were calculated based on SSR analysis. According to the results of Bayesian-based STRUCTURE analysis using SSR and SNP data, 94 bean genotypes were genetically divided into three main clusters. According to genetic distance based UPGMA dendrogram obtained from SNP analysis, 94 bean genotypes were divided into 2 main clusters corresponding Mesoamerican and Andean gene pools. The obtained results provide important information about the genetic structures of the studied bean cultivars and breeding lines. With the obtained results, it will be possible to develop breeding programs to develop new cultivars by using our gene resources.

     

兴义鸭LPL基因外显子8多态性与生长和肉质性状的关联性分析

脂蛋白脂酶（LPL）是动物脂质沉积和新陈代谢的关键酶,对生长和肉质发挥着重要作用。试验采用PCR-SSCP法和DNA直接测序技术相结合对兴义鸭LPL基因外显子8进行多态性检测,并分析其多态与生长和肉质性状的关联性。结果表明,在兴义鸭LPL基因外显子8首次检测到1个T1251C同义突变,产生三种基因型TT、TC和CC,2个等位基因T和C,基因型TT和等位基因T的频率分别为0．8077和0．8750,多态信息含量为0．1948,表现为低度多态,卡方（X2）检验表明T1251C位点的基因型分布在兴义鸭中未偏离Hardy-Weinberg平衡。最小二乘分析显示,TT基因型个体的宰前体重显著低于CC基因型（p〈0．05）,胸宽显著低于TC基因型白〈0．05）,推测等位基因C可能是兴义鸭生长性状的有利等位基因,可作为生长性状的一个标记性辅助选择位点。     

猪RBP1和RBP4基因的定位、组织表达谱分析、多态研究及相关分析

类维生素A（维生素A及其代谢产物）在动物的视觉、生长、繁殖、细胞的分化及胚胎发育等方面起重要的作用。利用猪的辐射杂种克隆板，将猪细胞视黄醇结合蛋白基因1（RBP1）和猪血浆视黄醇结合蛋白基因4（RBP4）分别定位在猪13号和14号染色体上。利用半定量RT－PCR方法，对这两个基因在成年五指山猪十二种不同组织（肺、骨骼肌、脾、心脏、胃、大肠、淋巴结、小肠、肝、大脑、肾、脂肪）的组织表达谱进行了分析。在猪的血浆视黄醇结合蛋白基因4中，发现一个单核苷酸多态位点（RBP4-A/G156），并用基于聚合酶链式反应的限制性片段长度多态性方法(PCR-RFLP)，对这一多态在莱芜黑猪、五指山小型猪、贵州小型猪、广西巴马小型猪和通城实验猪群中的分布进行了研究。在通城实验猪群中，进行了不同基因型与性状间的关联分析，发现其不同的基因型与胴体直长、胴体斜长、血红蛋白浓度、平均血细胞血红蛋白量、达上市体重日龄高度相关。在猪的生产和育种中，这一多态位点可能会成为有用的分子标记。     

长期定位施肥条件下黄土旱塬农田作物产量、水分利用效率的变化

以始于1979年的黄土旱塬黑垆土长期5种肥料试验为基础,研究了小麦、玉米一年一熟轮作条件下旱地作物产量及水分利用的变化。结果表明,无论气候年型如何,作物平均产量和水分利用效率大小依次为：有机无机肥结合（MNP）>秸秆还田与化肥配合（SNP）>单施化肥（NP）>单施农家肥（M）>单施化肥氮（N）>不施肥（CK）;MNP和SNP施肥方式在旱地农业生产中具有显著的增产和提高水分利用效率的作用,2种施肥方式下小麦平均产量较CK增加189%和158%,水分利用效率提高193%和 165%,玉米平均产量较CK增加125%和99%,水分利用效率提高121%和96%。随着试验年限的延长,化肥尤其是氮肥的增产效果受降水影响年际之间波动性很大, 但无机氮磷结合农家肥、无机氮磷配合秸秆还田能有效减缓产量的波动,起到抗逆减灾和稳定产量的作用。有机无机肥结合（MNP）和秸秆还田与化肥配合（SNP）是实现旱地有限水资源高效利用和旱地农业可持续发展的施肥方式。