松辽黑猪生长发育性能研究

[目的]为松辽黑猪新品系和吉松配套系选育优质肉猪新品种提供理论依据。[方法]选取松辽黑猪,松野杂猪和杜长大三元杂交育肥猪各15头,分成3个组分别为S、Y和B组,组内设3个重复,每个重复5头猪,在同一条件下进行饲养试验,并对其生长发育性能进行测定。[结果]S组松辽黑猪的胸围发育程度明显高于Y组松野杂猪和B组杜长大三元杂交猪,差异极显著（P〈0.01）,其他指标均差异不显著;Y组松野杂猪的增重速度、发育程度、屠宰率和产瘦肉率与B组杜长大三元杂交猪相比,差异均不显著。[结论]在增重速度和产肉率方面,松辽黑猪新品系和松野杂猪新品种的选育是成功的。     

Roles of Root Aerenchyma Development and Its Associated QTL in Dry Matter Production under Transient Moisture Stress in Rice

Abstract

Enhanced aerenchyma development in rice under transient drought-to-waterlogged (TD-W) stress promotes root system development by promoting lateral root production. This study analyzed the quantitative trait loci (QTLs) associated with the plasticity in aerenchyma development under TD-W stress. A mapping population of 60 F₂ genotypes of chromosome segment substituted lines (CSSL) derived from CSSL47 and Nipponbare crosses were grown in rootboxes and evaluated for shoot and root growth, and aerenchyma development (expressed as root porosity). The TD-W stress was imposed starting with water saturated soil condition at sowing and then to progressive drought from 0 to 21 days after sowing (DAS) prior to exposure to sudden waterlogging for another 17 days (21 to 38 DAS). We performed simple and composite interval mapping to identify QTLs for aerenchyma development. QTL associated with aerenchyma development was mapped on the short-arm of chromosome 12 and designated as qAER-12. The effect of qAER-12 on the plasticity in aerenchyma development under TD-W was significantly associated with the increase in lateral root elongation and branching. This resulted in greater root system development as expressed in total root length and consequently contributed to higher dry matter production. This qAER-12 is probably the first reported QTL associated with aerenchyma development in rice under TD-W and is a useful trait for the improvement of the adaptive capability under fluctuating soil moisture conditions.     

Differences in the behavior of the crossbred steers of different sire lines of Japanese Black cattle

We determined differences in the behavior of the progeny of two major sire lines of Japanese Black cattle by recording the behavior of 35 and 70 half-sib steers of sires from fast (FG) and slow (SG) growing lines, respectively. Two sire lines of steers were mixed and allocated to nine pens with 11–12 animals per pen. The proportion of steers lying was significantly (P < 0.001) higher in the SG line (43.4 ± 5.7% compared to 40.3 ± 6.0%). The proportion of time spent eating concentrate feed (FG: 12.1 ± 2.3%; SG: 11.4 ± 2.1%), drinking (FG: 0.8 ± 1.1%; SG: 0.4 ± 0.6%), licking the feed trough (FG: 0.4 ± 0.6%; SG: 0.2 ± 0.4%) and performing tongue-playing (FG: 3.1 ± 4.6%; SG: 1.0 ± 1.9%) was significantly higher in FG, whereas the proportion of time spent resting (FG: 41.5 ± 12.8%; SG: 43.7 ± 10.9%) and performing self-licking (FG: 1.7 ± 1.4%; SG: 2.1 ± 1.3%) was higher in SG (all P < 0.05). These results show progeny of the FG sire engaged in more active behaviors compared to the progeny of the SG sire line.     

冀豆12遗传背景导入系蛋白、脂肪含量分布特征

以高蛋白品种冀豆12为受体亲本,不同来源、不同蛋白脂肪含量的大豆种质资源为供体亲本,构建了28个组合BC2F1后代群体,分析冀豆12遗传背景导入系后代蛋白、脂肪含量分布特征。结果表明,28个后代群体均有蛋白含量超高亲个体,超高亲个体比例介于4.0%～68.2%之间,超高亲比例≥40%的组合有18个,占64.3%,BC2F1后代群体蛋白含量以超高亲和偏高亲类型组合为主。而脂肪含量分布特征恰相反,BC2F1后代群体脂肪含量以超低亲和偏低亲类型组合为主,超高亲个体比例介于0～67.4%,超高亲个体比例≥40%的组合有7个,占25.0%,9个组合无超高亲后代。表明以冀豆12为遗传背景通过有限回交易选育高蛋白含量品种,而不易选育高脂肪含量品种。本研究结果为利用冀豆12培育高蛋白品种提供了依据。     

税费变化对国有林场商品用材林林木资产评估值影响分析

为完善国有林场森林资源的价值核算,更客观真实地反应其经营管理绩效。本文概述了我国林业税费体制的历史沿革,并以某国有林场为实例,在假设其它条件不变的前提下,分别以不征收特产税和将"两金"由20%调整为5%及二者兼而有之三种情况,具体分析了税费变化对林木资产评估值的影响。     

STS标记在扬麦158×淮麦18F_4群体中的应用及其与PPO活性的关系

小麦籽粒中的多酚氧化酶活性是导致酶促褐变的主要因素.选育低多酚氧化酶活性的品种是改良面制食品外观品质的重要途径之一.本研究利用位于小麦2A和2D染色体上PPO基因分子标记PPO18和STS01,对扬麦158×淮麦18组合的300个F4代分离株系进行PCR扩增,说明不同带型与PPO活性的相关性.结果表明用PP018扩增的300个分离株系中有59个扩增出876 bp(2aaa型)的目标片段,其活性均值为82.01;46个同时扩增出685 bp和876 bp的目标片段(2Aab型)其活性均值为163.41;其余195个扩增出685 bp的目标片段(2Abb型)其活性均值为233.73.方差分析表明三者的PPO活性差异达到极显著水平,其中基因型为2Aaa型的PPO活性值明显低于2Abb型;PPO18在本试验群体中对PPO活性的决定系数为66.61%;用STS01扩增的300个株系中都扩增出了560bp的片段,群体间没有差异.文中说明了两对引物在该群体中的效应及其与PPO活性的关系.     

矮小鸡在高原地区生长速度研究

通过对矮小鸡配套系在高原地区的孵化和饲养试验,测定不同周龄的生长发育,并与在高原适应性较强的藏鸡进行比较.研究结果表明,矮小鸡配套系在高原地区的适应性比较强.     

野生动物资源经济价值评价探讨

对野生动物资源的经济价值的表现形式、类型及野生动物的作用等作了简要的概括,针对我国野生动物资源利用现状,并按照野生动物利用情况的不同,初步提出了野生动物资源的商业价值和娱乐价值的估算方法。     

商品林企业有关会计问题研究

本文结合林木资源生产及资金运作特点 ,探讨了在商品林生产采取企业式经营、核算的前提下 ,商品林企业林木资源资产、收入、成本、费用的确认及计量问题。