金枪鱼延绳钓船机电混合动力系统节油效果分析

金枪鱼延绳钓渔业是远洋渔业的重要组成部分。金枪鱼延绳钓作业过程包括航行、作业两种完全不同的工况。航行工况时要求航速较高,作业工况时要求航速较低。为了满足这两种工况,采用柴电独立运行(PTH)方式机电混合动力系统。机电混合动力系统由柴油机推进系统与电力推进系统两部分组成。高航速时使用大功率的柴油机模式,低航速时使用小功率的电力推进模式。上海远洋渔业有限公司近两年先后两批次建造了5条装备了PTH方式机电混合动力系统金枪鱼延绳钓船。根据实船测试,在作业期间,不同船型起钩阶段节油25%和8%,航行节油均达14%。通过计算分析,使用PTH方式,机电混合动力系统增加的初始投资成本可通过节油方式在4年内回收。综合节油效果显示,使用电力推进比使用柴油机推进可以节油15%~20%,达到了良好的节能减排、降低运营成本的效果。     

Breeding for improved appearance of large rainbow trout in two production environments

A quantitative genetic analysis was performed to study potential to breed for improved body shape, skin colour and skin spottiness of large rainbow trout in sea and fresh water production environments, and in different stages of growth. The results showed that heritabilities in both production environments were moderate for body shape and skin colour and very high for skin spots. For body shape and skin spots, genetic correlation between the two production environments was high (r_A≥0.90), revealing weak genotype‐by‐environment interactions across the environments. For skin colour, genetic correlation between the environments was positive (0.78) but lower than for body shape and skin spots, indicating moderate genotype‐by‐environment interactions. Genetic correlations between 2‐ and 3‐year‐old fish were high for body shape and skin spots (r_A≥0.93) and moderate for skin colour (0.85), showing that differences among families persisted strongly during growth. The positive correlations between the environments and between the ages imply that selection in fresh water environment at a single point of time should lead to favourable correlated genetic responses in the sea and at the other stages of growth.     

Economic feasibility for producing Imperial Zebra pleco (Hypancistrus zebra) in recirculating aquaculture systems: An alternative for a critically endangered ornamental fish

Abstract

The L46 (Hypancistrus zebra) stands out as one of the most valuable Amazonian species in the international market for ornamental fish and faces a notable problem: the risk of extinction versus the demand for new specimens for aquariums. Considering that breeding in captivity can be a conservational tool for aquatic species and an alternative source for generating income, the objective of the present paper was to verify the economic feasibility of producing H. zebra in recirculation aquaculture systems (RAS), in different scenarios of rearing: residential breeding (S1), mid-size store production (S2) and large-scale production as a supplier (S3). The main profitability indicators used were: net present value (NPV), internal rate of return (IRR) and payback period (PP). The selling price per unit was fixed in US$260.15 (S1/S2) and US$156.09 (S3). The largest investments were made with the acquisition of broodstocks (S1/S2) and property (S3), while the highest costs were with labor (S2/S3) and taxes (S1). Only S1 demonstrated economic profitability (NPV 8.50%?=?US$28,187.85; IRR?=?74.71%; PP?=?1.80?years). Conclusion: the production in this study appeared to be profitable on smaller scales, however the profitability of large-scale production depends upon reducing expenses and increasing the selling price.     

原鸡与茶花鸡杂交F_1代体尺性状与体重相关性分析

以原鸡(Gallus Gallus)与茶花鸡杂交F1代为试验对象,采用通径分析方法研究了第四到第十周龄体尺性状与体重间的相关关系。结果表明:各体尺性状与体重存在一定的相关性,相关密切程度存在周龄间差异。第四、六周龄时,体斜长与体重相关性最大、胸骨长其次、胫长次之,胸深和髋宽最小;第八、十周龄时,胸骨长与体重相关性最大、胫长其次、体斜长次之。生长前期体斜长、胫长对体重直接作用较大,后期胸骨长作用最大。对体重决定程度各周龄按大小依次排列为:第四、六周龄时体斜长、体斜长与髋宽及体斜长与胫长的共同作用等,第八周龄时体斜长、胫长等,第十周龄时主要为胸骨长、其它性状决定系数均偏小。由此,生长发育前期应加强对体斜长和胫长的选择力度,后期则应加强对胸骨长的选择力度。研究结果将对野生原鸡的开发利用和家鸡的杂交改良、选育实践具有实际意义。     

海水养殖杂交鲟对环境变化耐受性的试验研究

试验结果表明:海水养殖杂交鲟的适宜温度为5.0~22.0℃,临界上限水温为26.0℃,临界下限水温为3.0℃;耐受盐度的范围比较广泛,为1.0~38.0,适宜养殖的盐度为8.0~32.0;耐pH值的范围为4.7~9.8,适宜养殖的pH值为6.9~8.8。杂交鲟对环境变化耐受性范围较大,可以保证杂交鲟可以更好地适应其生存环境,以避免由于环境因子的激变造成海水养殖杂交鲟的大规模死亡。     

杂交水稻不同器官镉浓度与累积量

以生长于盆钵中的两系杂交稻两优培九、扬两优6号和103S/郑粳2号及三系杂交稻丰优香占、K优818和汕优63为材料,移栽前盆土内加入镉（Cd）,使土壤Cd浓度为100 mg/kg,研究水稻植株不同器官Cd的浓度和累积量。与未加Cd的对照相比,Cd处理降低了两优培九和103S/郑粳2号的产量,其主要原因是每穗粒数减少,而对其余组合的产量无显著影响。水稻植株对Cd吸收及分配存在着基因型差异,以汕优63累积量最多,K优818累积量最少。水稻植株不同器官Cd的浓度和累积量的大小顺序为根>茎鞘>叶片。籽粒不同部位Cd的浓度大小顺序为糠层>颖壳>精米。精米中Cd累积量仅为谷粒Cd累积量的30%左右。在抽穗期和成熟期,同一器官Cd浓度及累积量呈显著或极显著正相关,但不同器官之间的相关不显著。在6个供试的杂交稻组合中,精米中Cd的浓度以扬两优6号最高,K优818最低。对不同杂交稻组合植株中Cd浓度和累积量差异的原因进行了讨论。     

油茶低产园品种更新改造嫁接研究

[目的]解决油茶大树嫁接成活率低,品种更新成本高等问题。[方法]对不同嫁接时间、不同嫁接方法、不同砧木粗度、接穗不同成熟度嫁接进行研究。[结果]砧木用直径4～6 cm的大枝,接穗用当年抽生的半木质化绿枝带一叶,5月中下旬至6月上旬进行皮下腹接,9月补接,嫁接成活率达94%以上。[结论]用该研究成果可在1年内品种更新嫁接成功,降低低产园品种更新改造成本。     

稻瘟病自然病圃的建立及初步鉴定效果

2002~2004年在广西平南县稻瘟病重发区建立自然病圃,对2384份早晚造材料进行鉴定。结果表明,该自然病圃早造发病较重(叶瘟除外),晚造发病较轻,早造是抗性材料最佳筛选鉴定季节;诱发品种的选择应把握早、中、晚熟品种的搭配,以满足不同熟期抗病材料筛选的需要;双亲或其中之一具有抗病血缘,有助于筛选到稻瘟病抗性强的选系材料。     

小麦花培育种技术研究

对5个小麦不同组合基因型的F1,F2,F3花药进行培养,结果表明:不同组合基因型在同一杂种世代的花药愈伤组织诱导率、愈伤组织鲜重和绿苗分化率等方面存在较大差异,而同一组合基因型在不同杂种世代的花药愈伤组织诱导率、愈伤组织鲜重和绿苗分化率等方面差异较小。花药愈伤组织诱导率与绿苗分化率具有显著的相关性(r2=0.903)。以石4185为亲本配制的两个组合基因型,在F1,F2,F3都表现出较高的花药愈伤组织诱导率和绿苗分化率,说明石4185是理想的花培育种桥梁亲本。     

番茄品种渝粉109的DNA指纹图谱构建

用SDS法提取番茄杂一代品种"渝粉109"及其亲本的基因组DNA,通过RAPD-PCR分子标记方法,构建其DNA指纹图谱,用于种子纯度鉴定。利用200个RAPD随机引物,以杂一代品种及其亲本的基因组DNA为模板组进行筛选,结果显示:8个RAPD引物的DNA条带表现出多态性,其中R3能稳定地在亲本之间扩增出互补的特异条带。经定向验证、种子真伪鉴定、纯度鉴定,表明构建的渝粉109指纹图谱有效。