玉米秸秆消化率全基因组关联分析

48h体外干物质消化率（48h in vitro dry matter digestibility, 48h IVDMD）是衡量青贮玉米品质的重要指标。为了初步探究玉米秸秆消化率的分子遗传机理,以341份玉米自交系为材料,于2018年在沈阳和通辽种植,收获后测定秸秆48h IVDMD。利用全基因组重测序获得的6 276 612个高质量SNPs进行全基因组关联分析,共检测到153个与玉米秸秆消化率显著相关的SNPs位点（P<1.0×10^-6）,4个SNPs显著水平在P<1.0×10^-8以上;共找到38个秸秆消化率的候选基因,主要涉及细胞生长发育、防御反应和信号转导等生物学功能。     

辛亥革命前后张謇与袁世凯的交往

张謇与袁世凯的交往长达三十余年,他从最初的相识荐袁、拥袁合作、相互借重到后来的分离,张謇曾幻想依靠袁世凯实现自己“实业救国”的抱负,却以失败而告终。二人分分合合,充满波折的交往过程反映了中国近代资本主义发展的艰难与坎坷。     

龙井市农村经济灰色关联度分析

利用灰色系统理论中灰色关联度分析的方法，龙井市近几年来农村经济分3个层次进行了系统、全面的分析。     

学会改革与发展面临的问题及对策

随着社会主义经济体制的逐步完善,改革的不断深化和对外开放的进一步扩大,学会在组织体制、管理模式、运行机制和活动方式等方面,还不能完全适应社会主义市场经济的要求,在综合分析学会存在诸多问题以及面临激烈竞争和严峻挑战的基础上,针对农业学会目前现状,提出了对策,以及今后努力发展的方向。     

Growth and development of Cuscuta chinensis Lam. and its impact on selected crops

The growth and development of Cuscuta chinensis Lam., and the effects of the holoparasite on the growth and yield of tomato ( Lycopersicon esculentum ), chilli ( Capsicum annuum ) and rice ( Oryza sativa ) were investigated in pot experiments under glasshouse conditions. 'Mature' and 'immature' seeds of C. chinensis showed 15 and 47% germination, respectively. The independent life duration of seedlings from 'immature' seeds was 6 days shorter than 'mature' seeds (19 days). Cuscuta chinensis formed haustoria on chilli and tomato, but not on rice seedlings. Infection with three C. chinensis seedlings per host plant reduced leaf area, dry weight, carbon and nitrogen content by 78–84% and 27–44% in tomato and chilli plants, respectively. Dry weight of C. chinensis was 0.63 g per pot in tomato, and 0.24 g per pot in chilli. Carbon and nitrogen content of C. chinensis was 0.189 and 0.028 g per pot, respectively, when grown with tomato. When it was grown with chilli, the carbon and nitrogen content of C. chinensis was 0.001 and 0.007 g per pot, respectively. Cuscuta chinensis reduced the fruit yield of tomato and chilli by 72 and 29%, respectively. The results indicated that tomato is a preferred host of C. chinensis compared with chilli, and rice is not preferred. In the host–parasite associations, C. chinensis suppressed growth and yield of chilli and tomato by diverting the elaborated products of metabolism of the hosts.     

Genetic risk factors for osteochondrosis in various horse breeds

Osteochondrosis (OC) is an injury to cartilage canals with a following necrosis in the growth cartilage, from there it can develop to osteochondrosis dissecans (OCD). Due to its high impact in the equine industry, new insights into predisposing factors and potential high‐risk genetic variants are warranted. This article reviews advancements in quantitative and molecular genetics in refining estimation of genetic parameters and identifying predisposing genetic loci. Heritabilities were highest for hock OC with estimates at 0.29–0.46 in Hanoverian warmblood and Norwegian trotters, whereas in Thoroughbreds only very low genetic variation seemed to be present in hock OC lesions. Whole genome scans using the Illumina Equine SNP50 or SNP70 Beadchip were performed in Thoroughbred, Standardbred, French and Norwegian trotter, Hanoverian and Dutch warmblood. Validation studies in Spanish Purebred and Hanoverian warmblood horses corroborated OC risk loci on ECA 3, 14, 27 and 29. Particularly, a strong association with hock‐OCD was found for a single nucleotide polymorphism (SNP) on horse chromosome (ECA) 3 upstream to the LCORL gene. Gene expression and microRNA analyses may be helpful to understand pathophysiological processes in equine OC and to connect OCD‐associated genomic regions with potential candidate genes. Furthermore progress in elucidating the underlying genetic variants and pathophysiological changes in OC may be expected from whole genome DNA and RNA next‐generation sequencing studies.     

Multimarker and rare variants genomewide association studies for bone weight in Simmental cattle

Bone weight, defined as the total weight of the bones in all the forequarter and hindquarter joints, can reflect somebody conformation traits and skeletal diseases. To gain a better understanding of the genetic determinants of bone weight, we used a composite strategy including multimarker and rare‐marker association to perform genomewide association studies (GWAS) for that character in Simmental cattle. Our strategy consisted of three models: (i) A traditional linear mixed model (LMM) was applied (Q+K‐LMM); (ii) single nucleotide polymorphisms (SNPs) with p‐values less than .05 from the LMM were selected to undergo the least absolute shrinkage and selector operator (Lasso) in the second stage (LMM‐Lasso); (iii) genes containing two or more rare SNPs were examined by performing the sequence kernel association test (gene‐based SKAT). A total of 1,225 cattle were genotyped with an Illumina BovineHD BeadChip containing 770,000 SNPs. After the quality‐control procedures, 1,217 individuals with 608,696 common SNPs and 105,787 rare SNPs (with 0.001 < minor allele frequency [MAF] <0.05) remained in the sample for analysis. A traditional LMM successfully mapped three genes associated with bone weight, while LMM‐Lasso identified nine genes, which included all genes found by traditional LMM. Only a single gene, EPHB3, surpassed the significance threshold after Bonferroni correction in gene‐based SKAT. In conclusion, based on functional annotation and results from previous endeavours, we believe that LCORL, RIMS2, LAP3, PRKAR2B, CHSY1, MAP2K6 and EPHB3 are candidate genes for bone weight. In general, such a comprehensive strategy for GWAS may be useful for researchers seeking to probe the full genetic architecture underlying economic traits in livestock.     

Association analysis for detecting significant single nucleotide polymorphisms for phosphorus-deficiency tolerance at the seedling stage in soybean [Glycine max (L) Merr.]

Tolerance to low-phosphorus soil is a desirable trait in soybean cultivars. Previous quantitative trait locus (QTL) studies for phosphorus-deficiency tolerance were mainly derived from bi-parental segregating populations and few reports from natural population. The objective of this study was to detect QTLs that regulate phosphorus-deficiency tolerance in soybean using association mapping approach. Phosphorus-deficiency tolerance was evaluated according to five traits (plant shoot height, shoot dry weight, phosphorus concentration, phosphorus acquisition efficiency and use efficiency) comprising a conditional phenotype at the seedling stage. Association mapping of the conditional phenotype detected 19 SNPs including 13 SNPs that were significantly associated with the five traits across two years. A novel cluster of SNPs, including three SNPs that consistently showed significant effects over two years, that associated with more than one trait was detected on chromosome 3. All favorable alleles, which were determined based on the mean of conditional phenotypic values of each trait over the two years, could be pyramided into one cultivar through parental cross combination. The best three cross combinations were predicted with the aim of simultaneously improving phosphorus acquisition efficiency and use efficiency. These results will provide a thorough understanding of the genetic basis of phosphorus deficiency tolerance in soybean.     

鸡脚重性状的全基因组关联分析

鸡(Gallus gallus)脚重性状为鸡产业中的重要经济性状.为了揭示鸡脚重性状的遗传基础,寻找可用于鸡脚改良的分子标记,本研究以核心群京海黄鸡为实验动物,测定其脚重,利用简化基因组测序技术在整个基因组范围内检测与脚重相关的SNPs.共检测到16个与脚重相关的SNPs位点,其中13个集中分布在4号染色体上72.8～77.9 Mb区域;2个SNP位点rs475641139和rs475548810达到5％ Bonferroni全基因组显著水平(P＜5.5E-07),其余位点达到全基因组潜在显著水平(P＜1.1E-05).筛选每个SNP周围1 Mb区域内的基因,共找到9个可能的候选基因,并使用基因本体论(Gene Ontology,GO)数据库对9个候选基因的细胞组分、分子功能和参与的生物学进程进行了分析.结果表明二氢蝶啶还原酶(dihydropteridine deductase,QDPR)基因、LIM域结合蛋白2(LIM domain-binding protein 2,LDB2)基因、类184B家族(family with sequence similarity 184 memberB,FAM184B)基因、复合信号免疫球蛋白J结合蛋白(recombination signal binding protein for immunoglobulin kappa J region,RBPJ)基因、纤维母细胞生长因子结合蛋白2(fibroblast growth factor-binding protein 2,FGFBP2)基因、富亮氨酸重复蛋白5(F-box and leucine-rich repeat protein 5,FBXL5)基因、胆囊收缩素受体A(cholecystokinin receptor type A,CCK1R)基因、肌动蛋白互作蛋白1 (WD repeat containing protein 1,WDR1)基因和类桶状蛋白4(tubby like protein 4,TULP4)9个基因和4号染色体72.8～77.9 Mb区域可能为影响鸡脚重性状的重要候选基因和潜在功能区域.本研究为鸡脚重性状的标记辅助选择提供了理论依据.     

Genome-wide Association Study of Teats Number Traits in Kele Pigs

Teats number is one of the most important reproductive traits,and closely related to the economic benefit in pig industry.In order to reveal the underlying genetics of left teats number,right teats number and total teats number traits,a genome-wide association study（GWAS）was performed.Samples of DNA were collected to genotyping for 22 Kele pigs using the Illumina Porcine SNP 60K Chip.The GWAS was performed using a mixed-effects model and linear regression approach.When a genome-wide threshold was determined using the Bonferroni method（P<2.06E-5),4 single nucleotide polymorphism（SNP）markers were potentially associated with left teats number,right teats number and total teat number.However,3 SNPs were significant associated and 18 SNPs were potentially associated in chromosomes level.304 Ensembl genes were retrieved around 1 cM of the associated SNPs.The candidate genes in Wnt and Fgf signaling pathway（BTRC,FGF5,FGF8,BMP3,RASGEF1B and HMGB3）might have effect on target traits.These results provided valuable information about the selective breeding for Kele pigs.