Genomewide association study of immune traits in chicken F2 resource population

Immune traits play pivotal roles in animal immune capacity development and disease resistance. Single nucleotide polymorphisms (SNPs) are common forms of genetic variations among individuals, which are thought to account for the majority of inherited phenotypic variations. In this study, we performed genomewide association, using the Illumina 60K SNP BeadChip studies to detect molecular markers and candidate genes associated with immune traits in an F2 population. Sixteen immune traits were measured. We identified 85 significant SNPs (p < 2.98 × 10^?6) with 5% as the genomewide significance threshold, 380 SNPs of suggestive significance (p < 5.96 × 10^?5) from simple model (general linear model, GLM) and 15 SNPs of suggestive significance (p < 5.96 × 10^?5) from the compressed mixed linear model (MLM), which were also found in GLM (six significant SNPs and seven suggestive SNPs). Three significant SNPs (GGaluGA151406, Gga_rs14554319 and Gga_rs13593979) and candidate genes (LYRM4 and KTN1) were found to be associated with avian influenza antibody titres, and the first two SNPs are from the results of two‐model analysis. For the immune organs, through the analysis of GLM, 19 SNPs were found to be significantly associated with the thymus weight, 61 SNPs were significantly associated with the bursa of Fabricius weight, six of which were located within a 34‐Mb region (125 846 474–159 649 698 bp) on chicken chromosome 1 (GGA1). A candidate region relevant to haematological traits from GLM was found in GGA4 and 9 loci were located on it. Three loci (GGaluGA348521, Gga_rs16098446 and GGaluGA348518) within 179 kb (16 286 868–16 466 134 bp) on GGAZ from GLM provided evidence that this genomic segment may be relevant to red blood cell volume distribution width (RDW). Our study provides a list of significant SNPs and candidate genes that will be valuable information for unveiling the underlying molecular mechanism of immune regulation.     

Reproductive traits and diel activity of adultMonochamus saltuarius (Coleoptera: Cerambycidae) at two different temperatures

To investigate the reproductive traits and diel activity ofMonochamus saltuarius, 14 pairs of the adults were reared and observed at each of 20°C and 25°C. Both sexes were more active at 25°C than at 20°C irrespective of the presence or absence of light. A diel change in behavior during 24 h was found on 33% of a total of 48 observations of three age classes of both sexes. No significant difference was found in the mean longevity between sexes or between the two temperature conditions. The time required for reproductive maturation showed no significant difference within the same sex when reared at 20°C and 25°C. The mean oviposition period was significantly longer at 25°C (28.8 days) than at 20°C (12.2 days). The mean lifetime fecundity was significantly greater at 25°C than at 20°C. There was no significant difference in the oviposition ratio (number of eggs deposited/number of oviposition wounds excavated), oviposition rate or hatchability for females between the two temperature conditions.     

河北杨优树根萌条诱导及嫩枝扦插的研究

本文报导用根段促萌及嫩枝杆插方法进行河北杨成年优树的初繁试验。结果表明,根萌条诱导所需的有效积温(≥5℃)至少在206℃;嫩枝生根所需的有效积温(≥5℃)至少在200℃。根段的萌条均属皮部萌条类型;嫩枝的生根均属皮部生根类型。此试验方法可为河北杨无性系对比及筛选提供良好的优树初繁材料。     

长白山主要森林生态系统根系生物量研究

对长白山阔叶红松林、云冷杉林和亚高山岳桦林根系生物量的研究结果表明：３种森林类型根系总生物量排列顺序为阔叶红松林＞云冷杉林＞岳桦林;同土层深度下,根系生物量大致上也有上述规律,但第Ⅱ层根系生物量为云冷杉林＞阔叶红松林＞岳桦林;３种森林类型的根系生物量占其地上生物量及其总生物量的比例随着海拔升高而增加;根系大部分集中在０～６０ｃｍ土层中。     

不同化合态氮浓度对大豆根瘤菌结瘤和固氮作用的影响

不同化合态氮浓度对大豆根瘤菌结瘤和固氮作用的影响＊刘莉周俊初陈华癸（农业部农业微生物重点实验室,华中农业大学,武汉４３００７０）ＴｈｅＥｆｅｃｔｏｆＤｉｆｅｒｅｎｔＣｏｍｐｏｕｎｄＮｉｔｒｏｇｅｎＣｏｎｃｅｎｔｒａｔｉｏｎｏｎｔｈｅＮｏｄｕｌａｔｉｏ...     

人参不同部位无机元素含量测定

用原子吸收光谱仪分别测定黑龙江密山市种植人参的根、须、芦头、叶、叶柄中８种无机元素的含量发现根、须、芦头、叶、叶柄中均富含Ｃａ、Ｍｇ及多种人体必须微量元素,尤其是Ｍｎ含量叶中为１５３μｇ／ｇ,高出根、须、芦头、叶柄约２－５倍,Ｚｎ、Ｆｅ叶中含量也明显高于其他部位 。     

垄作栽培对夏玉米根系和叶片生长发育及产量性状的影响研究

研究了不同栽培方式对夏玉米根系及叶片生长发育和主要产量性状的影响。结果表明：垄作栽培夏玉米与传统平作栽培相比,根系发达,0～50 cm土层各层次根系干重均增加;各叶位叶片宽度增加,长度基部1～5叶位缩短、中上部增加;各期叶面积系数都较大。垄作栽培比传统平作增产12.1%。     

大口黑鲈生长性状的遗传参数和育种值估计

采用最佳线性无偏差预测法(BLUP法)对大口黑鲈(Micropterus salmoides)体质量、体长和体高的遗传参数和育种值进行估计.4月龄和6月龄的体质量遗传力分别为0.29±0.08和0.28±0.10、体长遗传力分别为0.31±0.08和0.26±0.10,6月龄的体高遗传力为0.29±0.10.这些性状的传力都属于中度遗传力(P＜0.01),表明在加性效应控制下,大口黑鲈生长性状具有较大的遗传改良潜力.6月龄的体质量与体长、体质量与体高及体长与体高的遗传相关分别为0.790±0.094、0.820±0.081和0.990±0.001,这些性状之间均表现为高的正遗传相关性(P＜0.01),说明在对体质量进行选择的同时,其他生长性状也可以获得相应的间接选择反应.从不同评定方法的秩相关来看,6月龄时综合育种值与体质量育种值、体长育种值以及体质量育种值与体长育种值的秩相关系数均达到了极显著(P＜0.01),分别为0.998、0.914和0.890,用综合育种值对大口黑鲈的评定名次排序与用单性状育种值排序的差异不大.本研究对大口黑鲈生长性状的遗传参数和育种值进行确定与分析,旨在为该物种的人工选育提供理论依据和技术参考.     

不同抗倒类型小麦植株节间性状与抗倒能力的氮肥调控效应

以抗倒伏小麦品种(生选6号、扬麦18、华成3366)、易倒伏小麦品种(扬麦13、扬麦22、扬麦24)为材料,设置施纯氮180 kg/hm2(N180)、240 kg/hm2(N240)2个氮素水平,研究不同小麦品种植株基部节间性状与抗倒伏能力对氮肥调控效应的差异。结果表明：与 N180相比,随着施氮量增加,易倒伏型小麦品种抗倒伏指数平均降低35.98%,抗倒伏型小麦品种抗倒伏指数平均降低1.12%,易倒伏型小麦的抗倒能力在不同施氮水平间的差异大于抗倒伏型小麦的;易倒伏小麦N240处理植株基部节间直径、半纤维素含量、纤维素含量、K素含量与薄壁组织厚度低于N180处理的,5个参数的降幅分别为12.60%、16.36%、19.04%、34.59%、27.48%;抗倒伏小麦N240处理植株基部节间直径、半纤维素含量、纤维素含量、K素含量和薄壁组织厚度较N180处理降低,降幅分别为5.13%、7.97%、3.74%、26.73%、15.70%;易倒伏小麦N240处理植株基部节间抗折力、针刺力、木质素含量与大维管束面积低于N180处理的,而抗倒伏小麦以上4个参数在2个施氮水平间无显著差异;与N180处理相比较,易倒伏小麦品种N240处理植株基部节间小维管束数降低,抗倒伏小麦品种的升高;与抗倒伏品种相比,易倒伏品种植株基部节间抗倒伏能力对施氮水平响应敏感。综合以上分析可知,增施氮肥主要是影响了易倒伏小麦植株的基部节间抗折力、针刺力、木质素含量、大维管束面积及小维管束数,从而使易倒伏小麦抗倒性降低。     

不同苜蓿品种主根受伤后同工酶变化

研究根系发育能力不同的苜蓉品种在主根受到伤害时同工酶的变化规律,结果表明,主根受伤前,根系发育能力强、中和弱的无棣、陇东和北疆苜蓿,处理与对照间脂酶和超氧化物歧化酶同工酶无明显差异,根组织脂酶同工酶的酶带数多于叶片。根组织和叶片超氧化物歧化酶同工酶的酶带数相同。主根受伤后,无棣和陇东苜蓿根组织脂酶同工酶的酶带数均比对照多１２上,但二者的变化方式不同。无棣苜蓿叶片脂商工酶的酶带数我于对照,无棣和陇东