水稻根系空间分布特性的数学模拟及应用

为了明确水稻根系在土壤中的空间分布特性,通过根箱试验,获取水稻根系坐标数据,采用方程 Y = α(1-b^X)（Y为根系累积长度,X为横向分布距离或纵向分布深度）建立根系纵向和根系横向分布模型,并利用模型分析田间水分管理对水稻根系生长及分布的影响.结果表明,水稻分蘖期和成熟期,约88%的根系分布在10 cm深度土层内,60%~70%根系分布在10 cm的横向范围内,其纵向和横向累积长度的变化均可用方程Y = α(1- b^X)模拟.水分管理影响水稻根系生长数量和纵向分布,但不影响根系横向分布.间隙灌溉水稻根系分别比湿润灌溉和水层灌溉水稻根系分布深0.6和3.5 cm,根系长度分别比湿润灌溉、水层灌溉水稻多19.8%与26.4%,根系数量分别比湿润灌溉、水层灌溉水稻多28.3%及21.0%.平均角度的变化具有同样的趋势.     

Agroforestry education and training in Latin America

Regional/Country Report

Agroforestry education and training in Latin America     

农业标准化生产及其管理系统开发平台研究

分析中国农业标准化生产现状，发现其中存在的问题，提出与农业信息技术结合是解决问题的途径之一。而专家系统开发工具（平台）是农业信息技术的关键技术之一，它作为一种开发专家系统的通用工具，使农业领域专家无需掌握过多的编程知识就能建造性能良好的专家系统，从而能有效克服目前农业标准化生产中存在的问题。基于此介绍了将农业标准化生产和专家系统开发平台结合起来建立农业标准化生产管理系统开发平台的建立基础、设计思路、技术路线以及平台功能，并阐述了农业标准化生产管理系统开发平台的应用前景。     

Lipid composition of lees from Sherry wine

In this paper, we describe the study and characterization of the lipids from lees of Sherry wine, one of the main byproducts from the wine-making industry in the Jerez/Xeres/Sherry denomination of the origin zone in Jerez de la Frontera, Spain. The lipid content, extractability, classification, fatty acid composition, and its main chemical characteristics have been determined in order to evaluate their potential use as a food or food additive.     

Assessment of Boron Application in Chestnuts: Nut Yield and Quality

A field trial was conducted between 2006 and 2009 in order to quantify the effect of boron (B) application on the yield and quality of chestnuts. The trial was established in an acid soil derived from siliceous schist and two levels of B were applied. Fruit abortion and nut yield per tree were measured, and nut quality parameters and chemical composition of the kernel were determined. Foliar B concentration was 8.6 mg kg^?1 in the control trees and 48.4 mg kg^?1 in fertilized chestnuts. Boron improved fruit setting and promoted nut production by 77%. In 2008, the occurrence of cold temperatures enhanced the effect of B on fruit setting, which was four-fold, whereas with the normal temperatures of 2009 the increase was lower. The drought of 2009 was responsible for the ruinous chestnut caliber and shell cracking. Boron induced a significant increase in the crude fat of chestnut kernel.     

猪两种腹泻病毒混合感染的病原诊断

对我省流行的疑似猪病毒性腹泻进行了病原诊断，通过细菌培养、ＲＮＡ电泳和电镜形态观察等辅助诊断和免疫萤光特异性诊断，确诊该病病原为猪传染性胃肠炎病毒（ＴＧＥＶ）与猪流行性腹泻病毒（ＰＥＤＶ）的混合感染，混合毒代号为ＴＰＶ３。     

Relationship between levels of IL-2, TNF-α and nitric oxide in aqueous humor after intraocular lens implantation

AIM: To investigate the relationship between the level of interleukin-2 (IL-2), tumour necrosis factor-α (TNF-α) and nitric oxide (NO) in aqueous humor after intraocular lens implantation. METHODS: New Zealand rabbits were divided randomly into three groups: (1) control group; (2) extracapsular cataract extraction group (ECCE); (3) extracapsular cataract extraction and posterior chamber intraocular lens implantation group (ECCE+IOL). The inflammation in all experimental rabbit eyes was observed via zoom-photo slit-lamp microscope on 1, 3, 7, 14 d and 30 d postoperation. Meanwhile, aqueous humor was drawn for white blood cell (WBC) counting and classifying and for determining IL-2, TNF-α and NO₂^-/NO₃^- contents. RESULTS: (1) The level of IL-2 and TNF-α and NO₂^-/ NO₃^- in aqueous humor of ECCE+IOL group were higher than that in ECCE and control at 1 to 14 days postoperation, respectively, it increased to peak value at 3 to 7 days postoperation and decreased gradually two weeks postoperation; (2) The changes in IL-2, TNF-α and NO₂^-/NO₃^- in each group were basically similer; (3) The changes of IL-2 and TNF-α level were closely related with NO content in aqueous humor (r=0.69, P<0.01 and r=0.98, P<0.01). CONCLUSION: IL-2, TNF-α and NO play an important role in intraocular inflammation intraocular lens implantation.     

Growth and feed utilization of gilthead sea bream (<Emphasis Type="Italic">Sparus aurata</Emphasis>, L.) fed to satiation and restrictively at increasing dietary energy levels

Three isoproteic (47% protein) diets were formulated to contain graded levels of crude fat (diet D16:16%, diet D24: 24% and diet D32: 32%). Each diet was fed to satiation in three and to 80% satiation in two replicate groups of gilthead sea bream (Sparus aurata), having an initial body weight of 72–74 g. The trial lasted 81 days. Groups fed to satiation showed higher final body weight (FBW; 238.8–252.3 g vs. 218.0–229.3 g) and daily growth index (DGI; 2.49–2.65%/day vs. 2.27–2.34%/day) than those fed to 80% satiation. Feed intake was significantly different both for feeding level and for diet composition. Fish fed to satiation had higher feed conversion rate (FCR) compared to the 80% satiation groups (1.33–1.44 vs. 1.13–1.17; P ≤ 0.001). Within satiation groups, FCR was significantly lower in fish fed D16 compared to fish fed D32 (1.33 vs. 1.44, P ≤ 0.05), whereas no statistical differences were found within the 80% satiation groups. The increase in dietary lipid level did not improve growth performance, feed efficiency and protein utilization but decreased gross lipid efficiency. Conversely, a reduction in ration from satiation to 80% satiation decreased DGI, thus improving FCR. Feed costs were influenced by dietary energy level and feeding ratio, the lowest energy diet at 80% satiation being the most profitable combination among the variables.