罗氏沼虾高世代育种群体收获体重加性和显性遗传效应

精确地估计加性和显性遗传效应,可以提高选择准确度和加速遗传进展。本研究构建了343个罗氏沼虾(Macrobrachium rosenbergii)G7~G9育种群体全同胞家系(半同胞家系244个),测定了29523尾个体的收获体重。基于单性状动物模型,利用平均信息约束最大似然法(average information restricted maximum likelihood method,AIREML)估计了G7、G8、G9和G8+G9 4个数据集收获体重的方差组分。分析时采用了两种模型:(1)加性遗传效应模型,包含加性遗传效应和共同环境效应(A+C);(2)加显性遗传效应模型,进一步包括显性遗传效应(A+D+C)。结果表明,在A+C模型下,估计得到的4个数据集收获体重的遗传力范围在0.046~0.082,为低遗传力水平(h~2≤0.15)。在A+D+C模型下,估计得到的收获体重遗传力范围在0.063~0.096,显性方差组分比率范围为0.027~0.571。模型中包括显性遗传效应后,G8数据集收获体重遗传力的估计值变大,其余3个数据集的估计值变小。罗氏沼虾育种群体收获体重遗传力较低,表明需要引进性能优良的野生或改良群体,增加育种群体的遗传变异丰富度;4个数据集显性遗传方差比率值变化较大,表明需要新的算法并利用更多世代数据提高其估计值的准确性。     

网络环境下文献布局调整与阅览室服务功能拓展

随着计算机网络和数字图书馆技术的飞速发展,现有文献服务方式单一,已不能适应新信息环境下的读者需求。因此,改革文献、机构组织结构势在必行,本文结合我馆文献、机构组织结构改革实践,讨论了拓展阅览室信息服务功能的新模式,以适应读者的个性化、集约化信息需求。     

Pedohydrological case study of two apple-growing locations in South Tyrol (Italy)

South Tyrol in northern Italy is the biggest coherent apple growing area in Europe. Intensive orcharding is practised there within an area of about 18,000 ha. Irrigation represents a central factor of production in this region because of the local climatic situation (only about 500 mm precipitation per annum). But the way irrigation is applied there follows mostly subjective criteria. At many locations much more water is used for irrigation than the apple trees actually need. The consequence is that irrigation in this region is a very cost-intensive factor of production which is increasingly being discussed and criticized for both economic and ecological reasons. In the context of the current discussions about climate change, the question of protection of resources and the saving of water is becoming more and more relevant.This paper presents the results of soil-physical and soil-hydrological studies, which were done in summer 2008 on two neighbouring locations in the Etsch-Valley of the Vinschgau (South Tyrol). The studies were done to detect pedo-hydrological differences at irrigated orchards which are in immediate vicinity to each other. Because of rainy weather for a few weeks before there was no irrigation at both locations during the period of this study. This made it possible to observe both locations and their pedo-hydrological differences under the influence of a natural water supply. Mostly these differences are neglected in the irrigation practice. It turned out that not only the adjacency of the groundwater table of valley floor soils but also the substrate-specific differences have a crucial influence on the dynamics and the availability of soil water for the plants. Furthermore differences in the compaction of the soil surfaces may cause prolonged infiltration rates and thereby create longer time lags between the start of the irrigation and the resulting water supply in the rootzone.To optimize the irrigation practice in this region it is essential to provide an objective basis for the irrigation process. Accordingly, the term “precision irrigation” is increasingly discussed. But precision irrigation must be based on objective and quantitative criteria which focus primarily on the physical soil properties.     

离心泵压力脉动测试关键问题分析

分析了离心泵进口区域、压水室区域和出口区域压力脉动的特点,提出了用于压力脉动试验研究的测点布置方案,尤其是蜗壳隔舌区测点布置方案.分析了采样频率和采样时间对测试结果的影响,得出采样频率主导频域的频率范围,采样时间主导频域的频率分辨率.在给定频率分辨率的前提下,结合采样定理和FFT方法特点,建立了普遍适用的离心泵压力脉动测试采样频率和采样时间选取公式.比较了运用5种不同窗函数进行FFT分析时所产生的频域分辨率和频率幅值的差异,发现矩形窗函数比其他窗函数在捕捉主频脉动频率及保持频率幅值不失真方面具有一定的优势.     

质量-数量性状的遗传分析

本文阐述由自花授粉作物的两个纯系杂交而衍生的各种世代群体的质量-数量性状的遗传表达,根据遗传组成和加性-显性遗传模型下的基因效应,给出了各有关群体质量-数量性状的平均数和遗传方差的分量.在此基础上,论述了主、微基因遗传变异的统计测验和主、微基因加性、显性变异分量的样本估计方法。     

固原上黄农业生态经济系统建设试验示范研究

通过对固原上黄试验示范区农业生产中存在问题的调查分析,拟定了该区农业生态经济系统建设的总体构思、优化配置方案及实施技术。通过8年试验示范,研究了该区农业生态经济系统的结构功能特征及其变化,论述了该优化模型的可信度,进而对黄土丘陵西部地区农业生态经济系统建设提出了看法。     

低能N+离子束诱导小麦农艺性状变异的细胞学基础

用剂量不同的低能(E=30kev)N+离子注入小麦稳定品系CH3286干种子,对M3代植株的株高、生育期(抽穗期)、抗病性、穗型和产量等农艺性状的变异进行了分析,对产生这种诱变效应的细胞学机制进行了细致的研究。结果表明,N+离子注入对小麦农艺性状的影响主要表现在生育期(抽穗期)、株高、穗型和产量性状,对抗病性改善不大。对产量性状的影响主要表现在对千粒重、株粒重、株粒数的影响,使千粒重极显著的降低(F=0.01),而使株粒重和株粒数显著的增加(F=0.05),对穗长、穗颈长、剑叶长、结实小穗数的影响不大。低能N+离子束注入,影响M1代小麦植株花粉母细胞减数分裂,使中期Ⅰ细胞的染色体配对频率降低,单价体频率增高,出现环状染色体、染色体断臂和多价体;在减数分裂后期和末期细胞中,染色体桥、落后染色体、染色体断片和微核等染色体畸变频率比未注入小麦显著增高,其中以染色体断片和微核居多;染色体的畸变频率与离子注入剂量呈正相关,剂量越大,畸变频率越高,变异类型也相对较多。低能N+离子束诱导花粉母细胞减数分裂行为异常是其诱导小麦农艺性状变异的重要原因,并呈明显的剂量效应。     

Aplysinopsins - Marine Indole Alkaloids: Chemistry,Bioactivity and Ecological Significance

Aplysinopsins are tryptophan-derived marine natural products isolated from numerous genera of sponges and scleractinian corals, as well as from one sea anemone and one nudibranch. Aplysinopsins are widely distributed in the Pacific, Indonesia, Caribbean, and Mediterranean regions. Up to date, around 30 analogues occurring in Nature have been reported. Natural aplysinopsins differ in the bromination pattern of the indole ring, variation in the structure of the C ring, including the number and position of N-methylation, the presence and configuration of the C-8-C-1′ double bond, and the oxidation state of the 2-aminoimidazoline fragment. Aplysinopsins can also occur in the form of dimers. This review summarizes 30 years’ research on aplysinopsins. The origin, isolation sources, chemistry, bioactivity, and ecological functions of aplysinopsins are comprehensively reviewed.     

小麦粉储藏期间水分变化规律的探讨

通过将小麦粉在不同温度、不同湿度下模拟储藏试验,研究了储藏过程中小麦粉水分变化规律,结果表明,小麦粉在储存一段时间后水分可分别达到平衡状态,方差分析得出储藏环境的温度、相对湿度对小麦粉的水分有显著影响,且水分与储藏湿度和温度呈显著二元线性关系（Y＝a＋bX1＋cX2）。将小麦粉的水分变化与其它品质比较分析得出,小麦粉储藏时应控制水分低于14．0％,储藏条件控制为：湿度〈70％,温度〈20℃。     

辣椒素的生理功能及提取研究进展

介绍了辣椒素的化学组成和结构,探讨了辣椒素的生理作用,综述了近年来对辣椒素提取方法的研究,以期为辣椒素的广泛应用提供依据。