海南省香蕉生产的比较优势分析

作为我国香蕉生产的主要产区，海南香蕉的生产对我国整个香蕉产业的发展具有重要的意义。文章首先分析了海南香蕉生产的自然生态条件优势、品质优势和产业基础优势。在此基础上，采用作物区域比较优势的分析方法，逐一通过对海南香蕉与其他香蕉主产区的比较优势分析、海南香蕉同海南省内其他5种热带水果的比较优势分析以及1988～2007年海南香蕉生产的比较优势变动分析，以综合评价海南省香蕉生产的比较优势。结果显示，海南省香蕉生产具有综合比较优势和规模优势，但却缺乏生产效率优势。根据分析结果，文章最后提出了一些相关的政策建议。     

海南槟榔产业格局的成因分析及对策

槟榔在海南有近千年种植的历史，是海南第二大经济作物，在海南广泛种植。海南槟榔产量约占中国大陆产量的99%。海南作为槟榔生产大省，却成为湖南槟榔产业的原料供应基地，本文主要应用SWOT分析方法，对海南槟榔湖南加工的产业格局成因进行分析，并提出海南槟榔发展的对策。     

海南槟榔产业发展概况

槟榔(Areca catechu Linn.),为我国四大南药之首,具有固齿杀菌、消积化食、消脚气及驱虫等功效。中国引种栽培槟榔约1500多年的历史。目前,海南槟榔产业所带来的经济效益已经成为海南省东部、中部和南部山区200多万农民主要的经济来源之一。本文通过阐述海南槟榔的生产情况、主要槟榔种类、产业经营情况,分析和提出了现阶段海南槟榔产业发展存在的主要问题及其相应对策,以期促进海南省槟榔产业的可持续发展。     

国内外天然橡胶种植情况分析

从世界及国内2个角度对中国天然橡胶的种植情况进行分析,确定了中国天然橡胶种植在世界上的地位及发展趋势。通过计算效率优势比较指数、规模优势比较指数、效益优势比较指数,从生产资料利用率、种植专业化程度及经济效益角度,对中国天然橡胶五大主产区云南、海南、广东、广西和福建的综合比较优势进行了评定,确定了中国各天然橡胶产区在天然橡胶产业发展中的地位、特点及不足。     

基于TOPSIS法对海南不同产地槟榔花的质量综合评价

[目的]系统研究槟榔花中的生物活性物质和体外抗氧化能力,为海南槟榔花的药用价值评价及产品开发提供理论依据。[方法]以70%乙醇超声提取并测定比较海南15种源产地槟榔雌花和雄花的总酚、总黄酮和总生物碱含量,采用DPPH自由基清除法、FRAP法和ABTS法测定提取液体外抗氧化能力,TOPSIS分析综合评价槟榔花药用价值。[结果]槟榔雄花的抗氧化能力普遍高于雌花,鸡心槟榔的抗氧化能力低于普通槟榔,乌石农场槟榔雄花WPM的抗氧化能力最强。[结论 ]TOPSIS法可作为多指标综合评价槟榔花质量的模型。     

海南槟榔黄化病病原物的分子鉴定

槟榔黄化病是槟榔上的一种重要病害,如何快速检测该病原菌是防治该病的重要基础。利用植原体16SrDNA通用引物对海南感染黄化病的槟榔花苞总DNA进行巢式PCR扩增,获得约1.2kb的特异片段,并对扩增产物进行核苷酸序列测定。通过BLAST程序比较、系统进化树构建及iPhyClassifier分析表明,引起海南槟榔黄化病病原植原体属于翠菊黄化植原体组(16SrⅠ组),且为该组中一个新的亚组,即G亚组,现将其暂命名槟榔黄化植原体(Arecanut yellow leaf phytoplasma,AYL)。     

浅析海南茶产业发展现状及对策建议

海南具有得天独厚的茶叶生长自然条件,有近千年的茶叶发展历史。20世纪中后期海南茶产业鼎盛发展,90年代中期后急剧萎缩。针对目前海南茶产业现状,从人力资源、产业规模和布局、品牌打造与市场销售、文化引领、政府扶持等方面提出茶产业发展建议,以充分发挥海南省茶产业比较优势,全面提高茶叶质量效益、茶产业竞争力和茶产业持续发展能力。     

海南省民营天然橡胶生产县域尺度分布研究

根据比较优势原理分析了海南省各市县民营天然橡胶生产比较优势状况,并通过CAD和PS绘图软件进行空间表达,结果表明：海南有8、11、7个县（市）民营天然橡胶生产分别具有规模优势、效率优势和综合比较优势,主要分布在海南中北部区域。海南省应按照比较优势的原理进行民营天然橡胶生产结构的调整,实现天然橡胶产业的合理布局,稳定产业发展。     

海南槟榔黄化植原体分子检测及其系统发育关系研究

由植原体引起的槟榔黄化病是海南特色经济作物槟榔种植上的一种毁灭性病害。本研究通过PCR扩增测序、序列多重比对和系统发育分析,对海南部分代表性地区槟榔致死性病原植原体的序列信息与系统发育关系进行检测分析。结果表明：本研究检测的保亭、屯昌、万宁等海南部分代表性地区的槟榔黄化植原体的16S rDNA序列一致;BLAST分析表明各株系16S rDNA与16SrI组植原体同源性为100%。序列多重比对分析表明,本研究各槟榔黄化植原体株系与海南苦棟丛枝、长春花绿变、马松子变叶、辣椒黄化皱缩、蛇婆子丛枝、细圆藤丛枝和日本洋葱黄化、美国翠菊黄化等植原体同源性为100%;与已报道的海南万宁、印度、海南三亚的槟榔黄化植原体16S rDNA序列同源性分别为99.9%、99.9%、99.8%。系统发育分析表明,本研究槟榔黄化植原体与海南苦棟丛枝、长春花绿变、马松子变叶、辣椒黄化皱缩、蛇婆子丛枝、细圆藤丛枝等株系聚于一个分枝,支持率为100%。此外,在发病槟榔叶片、花穗、心叶等组织部位均可检测到植原体。研究结果表明,海南槟榔黄化植原体与海南苦棟丛枝、长春花绿变、马松子变叶、辣椒黄化皱缩、蛇婆子丛枝、细圆藤丛枝等植原体株系的同源性极高,槟榔黄化病很可能会以这些寄主植物作为病原传播载体进行传播扩散。     

越南紫薯脱毒种苗生产及高产高效栽培技术

为充分发挥海南气候资源优势,增强海南甘薯的市场竞争力,促进海南甘薯产业的发展,引进越南紫薯优良品种,并针对其研究建立了一套越南紫薯脱毒种苗产业化生产技术体系,集成了相配套的越南紫薯脱毒苗高产高效栽培技术。     

豫北优质大豆产业发展策略

针对豫北地区的大豆生产现状，从气候、土壤、品种、生态因素及市场需求等方面提出了优质大豆的发展策略与途径。     

Analysis of nutritional components of eight famine foods of the Republic of Niger

In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply.     

狗牙根诱变后代抗寒性评价

通过电解质外渗法和匍匐茎恢复试验对‘阳江’狗牙根及其12个通过形态鉴定选出的坪用价值高且花序密度低的诱变后代进行抗寒性鉴定。电解质外渗法结果表明:诱变后代间的抗寒性具有较大差异,其叶片半致死温度(LT₅₀)的变异范围为-7.6～-0.2℃(最低值与最大值相差7.4℃);参试材料抗寒性由强到弱依次为M18>M4>M26>M28> M22>阳江>M29>M31>M10>M37>M16>M1>M25,其中,有5个诱变后代抗寒性优于亲本,分别是M18、M4、M26、M28、M22。匍匐茎恢复实验结果表明:诱变后代M1、M22、M26、M31、M25在0℃和-5℃低温胁迫后的恢复生长率都高于亲本,恢复能力均优于亲本;M10、M37、M28在-5℃低温胁迫下,恢复生长能力低于亲本,抗寒性相对较弱,M16和M4在0℃和-5℃低温胁迫下,恢复生长率都低于亲本,抗寒性明显弱于亲本。综合2种方法鉴定结果显示:诱变后代M1、M25的恢复能力较强;M4、M28的叶片抗寒性较好,青绿期较长;M22、M18、M26的叶片抗寒性和匍匐茎恢复能力均较强;M29,M31的叶片抗寒性和匍匐茎恢复能力与亲本相似;M10、M16、M37的叶片抗寒性和匍匐茎恢复能力均较弱,整体抗寒性较弱。     

吉林省平安农业科学院大豆所大豆研究工作报告

1　吉林省平安农业科学院大豆研究工作简介吉林省平安农业科学院大豆研究所 ,设在吉林省长春市西安大路种子大厦内。现有科技人员 6人 ,其中研究员 2人 ,农艺师 2人 ,技术员 2人 ,定向培养研究生 2人。大豆研究所的主要任务是选育稳产、高产、优质及抗病虫大豆新品种 ;同时密切     

Comparisons of methods of scheduling irrigations of potatoes

Irrigation of Netted Gem potatoes was scheduled during three growing seasons by three methods: (a) when plants displayed first visual symptoms of moisture stress, (b) when indicated by a soil moisture budget involving estimated evapotranspiration, and (c) on the basis of tensiometer readings of soil moisture suction. When the tensiometer method of scheduling was used, the mean yields of tubers were 55.0 and 25.8 cwt/acre (6160 and 2890 kg/ha) higher than those obtained with the other two scheduling methods. Methods did not affect the specific gravity of potatoes. Method (a) scheduled irrigations least frequently. Scheduling by the budget method was not always adequate because it was based on the assumption that the crop extracted water from a constant 4 ft (1.2 m) profile from planting to full vegetative growth. In one year the budget method scheduled the first irrigation earlier than necessary and delayed the second irrigation during a critical period of crop growth. From full vegetative cover to harvest the irrigation schedules were alike for both the budget and tensiometer methods.     

湖南沅陵4种绿茶品质成分分析

以长沙县高桥相同嫩度茶鲜叶原料采用卷曲形毛尖茶加工工艺制绿茶为对照,分别对沅陵县齐眉翠峰、凤娇碣滩茶、干发茶和军大坪茶4种绿茶的主要生化成分与感官品质进行初步分析。结果表明,沅陵4种绿茶的茶多酚总量28.76%~30.34%,游离氨基酸总量2.35%~3.22%,咖啡碱含量3.00%~3.63%,水浸出物含量37.26%~40.07%,可溶性糖总量5.46%~5.65%,可溶性蛋白含量1.50%~1.74%,类黄酮化合物总量1.16%~1.79%,叶绿素总量1.36%~2.01%,儿茶素总量13.53%~16.20%。与对照相比,4种绿茶的茶多酚、可溶性糖和儿茶素总量均高于对照,除齐眉翠峰外其余3种茶样水浸出物和叶绿素总量均高于对照,除干发茶外其余3种茶样类黄酮化合物总量均高于对照。     

Comparison of two methods of PCNB application for control of Rhizoctonia infection of potatoes

A broadcast application of PCNB (Terraclor) resulted in a reasonably uniform distribution of the chemical in the soil with the concentration decreasing in a linear fashion with increasing depth in the soil profile. A banded application resuluted in a considerably higher chemical concentration at the 4–6 inch depth than at the 0–2 or the 2–4 inch depths. The problem of the lack of uniformity of chemical distribution could probably be solved by altering nozzle placement and size and allow use of the band method of application to minimize grower cost. More complete disking in the case of the broadcast treatment would probably result in a relatively uniform distribution of the chemical but at higher cost to the grower. PCNB application rates of 10, 15 and 25 lbs per acre broadcast and 71/2, 10 and 121/2 lbs per acre in a band significantly reduced the severity ofRhizoctonia infection of Russet Burbank potatoes but did not increase potato yields significantly.     

Prediction of the digestibility of the diet of horses: evaluation of faecal indices

Data from in vivo digestibility trial with four to six horses fed twenty-seven forage-based diets are used to calculate prediction equations for the digestibility of dry and organic matter, based on the crude ash (CA), crude protein (CP) and crude fibre (CF) contents of diets and faeces. The most precise prediction of dry-matter digestibility (r.s.d. = 0.032, R²= 0.80) was derived from a multiple regression including faecal (CP, CF) and dietary parameters (CF). Among faecal parameters, CP was the best single predictor of both digestibility (r.s.d) = 0.040, r²= 0.63) and dietary CP content (r.s.d = 0.028, r²= 0.59). For biological reasons we propose a non-linear model that allows prediction of dry- and organic-matter digestibility from faecal CP Content with reasonable Precision (r.s.d = 0.038, 0.036, r²= 0.65, 0.74, respectively). This will be adequate for many studies, especially for free-living animals in rangelands.     

橡胶树丛枝病病原的抗血清制备与应用

以感染橡胶树丛枝病病原的长春花为材料,制备得到橡胶丛枝病病原菌抽提液,以抽提液为抗原免疫家兔,制备抗血清,经微量沉淀测定,抗血清效价为１：２０４８。应用橡胶丛枝病抗血清检测橡胶褐皮病,无症苗木检出率达３０％－３７％,可疑的褐皮病树检出率达８５．７％。