大豆杂种世代蛋白质含量的相关及变化规律探讨

本文以杂交亲本及其F_2、F_4、F_5、F_6、F_7五个世代的资料分析了F_2蛋白质含量与亲本以及其它世代间的关系,结果表明:(1)双亲蛋白质含量高,杂种二代蛋白质含量也高;(2)F_2蛋白质含量与F_4、F_5、F_6、F_7均呈显著正相关;(3)杂种后代蛋白质含量有逐代下降趋势,不同组合下降幅度不一样,蛋白质含量高的组合下降幅度大于蛋白质含量低的组合。     

家系相关模型的探讨

探讨了家系相关模型的方法，并举例说明了应用。     

基于正弦函数拟合估算新疆棉铃虫及棉蚜的发生代数

以每年的1月1日起为日度计算起始日,以棉铃虫、棉蚜的物候学发育起点温度和发育上限温度为基准,利用单sine函数方法和日期预测法估算出新疆棉铃虫和棉蚜的发生代数.结果表明:棉铃虫和棉蚜在新疆分别可以发育完成3～4代和25～35代,地区之间的温度差异决定了棉铃虫和棉蚜在新疆不同地区发育代数不同.     

质量-数量性状遗传参数估计的P1、 P2、 DH联合分析方法

本文提出利用亲本P1、 P2及其DH三个群体联合分析包括两个位点主基因控制的质量-数量性状遗传的统计方法, 共建立了五类共22个遗传模型, 进而, 可采用AIC信息准则选择最适模型, 并通过适合性检验对所选择的遗传模型做进一步的检验。     

豫州913蛋鸡亲本不同羽色类型对子代雏鸡自别雌雄准确率的影响

研究结果表明，豫州９１３蛋鸡不同羽色类型的父本，其子代羽色自别雌雄准确率关异不显著；不同羽色类型的母本，其子代羽色自别雌雄准确率差异显著。其中，不同羽色类型的公鸡与白羽中有大量红锈羽的母鸡交配，后代雏鸡自别雌雄准确率最低（７９．３％）；不同羽色类型公鸡与纯白羽的母本交配，后代雏鸡羽色自别雌雄准确率最高（９３．６％）。     

杂色鲍野生群体与养殖群体自交和杂交子一代的RAPD分析

杂色鲍野生群体和养殖群体分别自交和杂交产生野生鲍自繁F1代(WW)、养殖鲍自繁子代(CC)、正交子一代(W♀×C♂,简称WC)和反交子一代(C♀×W♂,简称CW)4个群体,采用RAPD分析4个群体遗传特性。就多态位点比例、Nei基因多样性值和Shannon信息指数而言,WW群体比CC群体高;杂交群体WC的值分别为88.76%、0.3246和0.4811,比其余群体都要高,与群体WW最接近;另一杂交子代群体CW除多态位点比例比群体CC高外,其余参数均为最低。群体间的遗传距离分析表明,WW与各群体的遗传距离都较大,其中与CC群体的遗传距离最大,为0.0849,与两个杂交群体间的遗传距离分别为0.0772(CW)和0.0671(WC);CC群体与两个杂交群体间的遗传距离都较小,分别为0.0610(与CW)和0.0597(与WC);杂交子代间的遗传距离为0.0600;杂交群体WC与WW的遗传距离大于与CC的遗传距离,CW与WW的遗传距离也大于与CC间的遗传距离,两个杂交群体与亲本的遗传距离不对等,偏向养殖亲本。     

中国养老保险改革的政策效应分析

基于世代交叠模型,考虑中国经济“新常态”中出现的特点和趋势,分析中国养老保险改革中多种政策的潜在影响。研究结果表明：国家不能仅仅依靠延迟退休政策来应对老龄化问题,应保持社会养老保险制度的相对稳定、完善金融市场体系、提高资金运用效率。     

Effects of plant chemicals on the Cotton Bollworm,Helicoverpa armigera (Hübner): A multi-generation study

We studied the effects of feeding on different cotton cultivars with different gossypol contents on the development, reproduction and food plant utilization of three successive generations of Cotton Bollworm, Helicoverpa armigera (Hübner). Significantly higher larval survival rates were observed in three successive generations of H. armigera fed on cotton cultivar “ZMS13”compared with cultivars “M9101” and “HZ401”. There was a significant decrease in fecundity in the first generation compared with the second and third generations of cotton bollworms fed on “M9101” and “ZMS13”. Cotton bollworm generation significantly influenced mean relative growth rate, relative growth rate and relative consumption rate. The relative growth rate significantly decreased in three successive generations of H. armigera fed on the high-gossypol cultivar “M9101” compared with those fed on low-gossypol cultivar “ZMS13”. However, a significantly higher relative growth rate was recorded in the third generation than in the first generation fed on “M9101”. Measurements of development and food utilization at the individual and population levels over more than one generation ought to provide a more meaningful prediction of long-term and population dynamics of the cotton bollworm.     

传统孝道视角下农村养老模式的创新研究——以浙江S村“孝心基金”为例

针对当前农村养老面临的困境,从乡村善治的视角,厘清乡村精英民间力量、孝道文化和农村养老之间的关系,对浙江单村通过政府引导、“乡绅”主导、群众参与,弘扬传统孝道,设立孝心基金的实践进行专题研究,提炼总结农村养老的“单村经验”,并就如何完善这一模式进行了思考.     

Improving the estimation of realized effective population sizes in farm animals

Computation of inbreeding rate (Δ F ) must consider that inbreeding is delayed with one generation with respect to the idealized population when addressed using individual inbreeding coefficients. The expression relating inbreeding in generation t with inbreeding rate F _t  = 1 – (1– ΔF ) ^t should be more correctly written in real animal populations as F _t  = 1 – (1– ΔF ) ^{t −1}, as changes in allele frequencies occur in the equivalent co-ancestries in the previous generation. This simple approach is tested on simulated and real pedigrees thus demonstrating that: (i) the adjusted individual increase in inbreeding becomes stable in populations under random mating while the unadjusted parameter does not; (ii) regression of the unadjusted parameter over generations in pedigrees under random mating is highly significant while after correction it is not significant; and (iii) the variance of the adjusted parameter is reduced with the generations.