不同牙鲆群体遗传力和育种值分析

以牙鲆(Paralichthys olivaceus)抗病群体(RS)、RS(♂)与从日本引进的日本群体(♀)交配建立的群体(RJ)、日本群体(♂)与RS(♀)交配建立的群体(JR)、以及韩国群体(KS)为基础群体, 通过随机交配建立牙鲆家系, 研究了4个群体作为亲本的育种性能。待所建立的家系生长至19月龄左右时, 测量家系生长性状, 包括全长和体质量, 测量所得数据用SPSS及DMU软件中的REML算法和BLUP方法进行分析。结果显示, 从表型参数可以看出KS(♂)×RJ(♀)杂交后代表现出明显的生长优势。19月龄牙鲆全长和体质量的遗传力分别为0.301、0.295, 都属于中等遗传力。因此, 牙鲆群体具有较好的遗传改良潜力。全长、体质量育种值与其表型值的相关系数分别为0.838和0.827, 且呈极显著相关(P<0.01), 表明个体育种值的预测结果具有较高的准确性。对父母本分别进行育种值比较可知, 父本中KS的育种值最高, 母本中RJ的育种值最高, 因此选用KS(♂)和RJ(♀)杂交可培育出生长迅速的牙鲆新品种。本研究通过比较4个资源群体牙鲆生长性状的育种性能, 并以此作为筛选优良亲本群体的重要依据, 旨在为牙鲆新品种的成功选育奠定理论基础, 同时为牙鲆的进一步遗传改良提供重要的科学依据。

     

圆形无压隧洞恒定渐变流水面线计算的近似法

基于恒定渐变流基本微分方程,采用数值分析理论,得到流程与始、末段水深的解析函数,通过该函数可直接计算沿程水面线。该方法比《水工隧洞设计规范》中推荐的分段求和试算法更简单、便捷,特别对水深较敏感段。规范推荐试算法误差较大,并且逐段试算推求水深,将导致末端断面水深误差逐步累积,误差大,精度下降。通过工程实例计算比较得出:新解析法计算结果与规范推荐法(程序)计算结果基本一致,甚至优于规范推荐的分段试算法,完全满足工程实践要求。     

Simple prediction of crude protein content in vegetation growing on abandoned cultivated land

The accuracy of two simple methods was compared for the prediction of crude protein (CP) content of above‐ground plant material of mixed‐species composition on abandoned cultivated land in Japan. The first method is based on standard CP values (in g kg^?1 dry matter) for individual species (STV method) as listed in the literature. The second procedure (GLM method) was an application of the generalized linear model using the relative above‐ground biomass of monocots and legumes, total herbage mass, and day of year. Predictions were made at the quadrat scale, and for surveyed sites based on average of values for five or six quadrats in a single survey. A ‘leave‐site‐out’ method was adopted for model validation of the generalized linear model. The observed values of CP content ranged between 21·5 and 161·9 g kg^?1 dry matter (DM). With the STV method, the values of root mean square error (RMSE indicates average estimation error) were 50·9 at the quadrat level and 53·8 at the surveyed‐site level (both g kg^?1 DM). When a ‘leave‐site‐out’ validation was carried out, the RMSE‐values for the GLM method were 23·2 at the quadrat level and 13·2 at the surveyed‐site level (both g kg^?1 DM). We therefore propose adoption of the GLM method for the purpose of estimating the CP content in herbage on abandoned sites.     

济源市农业水价分析及其调整策略

科学合理的农业水价能起到价格杠杆作用,促使农业节约用水。以济源市为例,分析区域农业用水概况、农业水价现状及其存在问题,以全成本水价理论和能值价值理论为基础估算得到区域内主要灌区的农业成本水价;以亩均产值和亩均净效益为基础测算得到农民水价承受能力为0.11元/m3;参考计算结果,明确了农业水价的调整范围,针对济源实际,提出了农业水价调整策略。为济源市农业水价调整提供了参考依据,也可供其他地区农业水价调整借鉴。     

汉味小说的方言运用及民俗学价值

汉味小说中运用方言来原生态地表达当地民俗风情、民俗心理、民族情感和民众日常生活等习俗,凸显了武汉市民日常生活民俗、商业民俗、广场民俗、人生礼俗的全貌,是以文学形式间接表现出来的民俗资料,为民俗资料的收集、保存和传承提供了新途径,从而使汉味小说具备了丰富的民俗学价值。     

Review and analysis of documented patterns of agricultural research impacts in Southeast Asia

Based on a comprehensive search and review of the literature, 42 studies are identified for in-depth review and analysis of documented impacts of agricultural research from 1959 to 2009. This body of evidence is subjected to a systematic, quantitative scrutiny for the coverage and type of impact to derive patterns, gaps and trends in documented impacts of research in the subregion. The analysis offers compelling evidence that past investments in agricultural research in the region have been productive. In so doing, the study also reveals some persistent patterns and identifies a number of gaps between investments and documented impacts. Strikingly, the benefits are principally derived from rice improvement research, which has generated 86% of total documented benefits in the Southeast Asia region over the past five decades. In comparison with rice improvement research, evidence of impacts in other areas such as natural resource management and other commodities is minor. This suggests that there is considerably more certainty about the ability of rice research, particularly genetic improvement, to generate impact than is the case for other research foci.However, even for rice, the evidence has been patchy across time and space. There has been no comprehensive and subregion-wide attempt to inventory trends in adoption of improved rice varieties and document historical net benefits generated by this research effort. Despite the large-scale, long-term and sustained adoption of research generated rice technologies for smallholder farmers in this subregion, an impressive story on the impacts of agricultural research on long-term developmental goals still remains undocumented. The paper also reveals a declining trend in total documented net benefits from agricultural research in recent years, which is probably attributable to research lag times and changes in the intensity of impact assessment over time.     

一种导流洞快速封堵方式的研究与应用

九峰水库导流洞采用"埋设钢管拍门"方法对导流洞进口段进行突击封堵,解决了由于其他因素使得施工组织断档而出现的封堵混凝土排架及混凝土门槽缺位问题,起到工程应急作用。经多个工程实践证明该方法简便、经济,可为中小型水库等同类型工程导流洞封堵借鉴。     

基于SPAD值的木薯叶绿素含量预测模型

为了探讨木薯叶绿素含量的非破坏性快速测定方法,在测量叶片SPAD值、比叶面积和叶绿素含量的基础上构建通过SPAD值预测总叶绿素含量的数学模型。结果表明,叶绿素a对于SPAD值的贡献率大于叶绿素b;比叶面积和叶位显著影响SPAD值与总叶绿素含量的关系,在SPAD值预测总叶绿素含量的模型中导入比叶面积和叶位2个自变量可提高预测总叶绿素含量的精度;基于SPAD值、比叶面积、叶位预测总叶绿素含量的模型为C=-4.51+0.092 5 Spv+0.039 9 Sa+0.145 0（Lp）。     

应用体外产气法研究3种农业废弃物对黑山羊的饲用价值

为了测定甘蔗尾叶、香蕉茎秆、菠萝叶3种热带农业废弃物对海南黑山羊的饲用价值,采用体外产气法测定3种热带农业废弃物的体外干物质消化率和产气量,并测定其营养成分和单宁含量.结果表明:甘蔗尾叶、香蕉茎秆、菠萝叶的体外于物质消化率(IVDMD)依次为49.68％、61.86％和79.56％,饲料相对值(RFV)依次为62.65％、77.23％和139.81％.总产气量(GP)、IVDMD与粗蛋白质(CP)、酸性洗涤纤维(ADF)、中性洗涤纤维(NDF)均呈负相关,RFV与CP和总能量(GE)呈不显著正相关,而与ADF和NDF呈显著负相关(p＜0.05).综上所述,甘蔗尾叶、香蕉茎秆、菠萝叶对于海南黑山羊均具有一定的饲用价值,可作为黑山羊的粗饲料;在3种废弃物中,菠萝叶的饲用价值最高.     

Protein Hydrolysate from Visceral Waste Proteins of Bolti Fish (Tilapia nilotica): Chemical and Nutritional Variations as Affected by Processing pHs and Time of Hydrolysis

The main objective of the current work was to evaluate the proximate chemical composition and nutritional quality of amino acids of protein hydrolysates from viscera of Tilapia nilotica fish. The results of amino acid composition showed that all hydrolysates contained sufficient and/or excessive amounts of both essential and nonessential amino acids, with appreciable values of essential amino acid/nonessential amino acid ratio (0.77 to 1.59) and essential amino acid/total amino acid ratio (43.35 to 61.35). All protein hydrolysates had a high content of the flavor enhancer amino acids. The lowest values of essential amino acids were found for phenylalanine and methionine with chemical scores ranging from 0.04 to 0.77 and 0.09 to 1.06, respectively, except for 18 h hydrolysates. The protein efficiency ratio had values greatly exceeding 2.0, which is considered a high quality. On the other hand, the levels of sugar and ash contents ranged from 2.69 to 3.32 g L^?1 and 0.48 to 2.1%, respectively, with 9.2 to 14% dry matter. Mineral composition showed that sufficient amounts of calcium, sodium, potassium, magnesium, and iron were present. The results suggest that the studied hydrolysates are appropriate for use in balanced human or animal diets.