甘肃省金塔县甜菜生产中出现的问题及对策

甘肃省金塔县的甜菜含糖近年来有下降趋势。调查表明, 其主要原因为采用甜菜间、套种其他作物造成的。甜菜间作套种,一是施肥量大, 往往导致三要素比例失调;二是增加了灌水次数及灌水量;三是导致病害加重（ 特别是丛根病） ;四是品质下降,含糖率低下。解决办法一是禁止小麦与甜菜套种,调整好产区布局;二是实行按糖论价收购办法;三是制定相应的稳糖高产栽培措施等     

小麦甜菜带田的理论与实践

小麦(胡麻)、甜菜带状种植,是甘肃省河西走廊甜菜产区近年发展起来的一种甜菜种植形式,简称小麦、甜菜带田。它是期着生产条件的改善、农业生产水平的提高而产生的一种新的甜菜种植制度,这一制度不仅为甘肃河西走廊,而且为我国西北一年一熟制灌溉农业甜菜产区,缓解粮糖争地矛盾,建设粮糖商品生产基地,大幅度提高土地生产力,开辟了一条新的途径。小麦甜菜带回发展概况及增产效果河西走廊的小麦、甜菜带田,是在小麦、甜菜间套种基础上产生和发展起来的,开     

小麦套种大豆对大豆品种的要求

小麦套种大豆对大豆品种的要求甘肃省农科院经作所马志军小麦套种大豆已成为甘肃省中部沿黄灌区和河西灌区发展大豆的重要途径。套种大豆由于受与小麦共生期的不利影响．产量水平不高。因此，选育适宜与小麦套种的高产大豆新品种，无疑是我省大豆育种工作重要的研究内容。...     

地膜甜菜密度试验简报

地膜甜菜密度试验简报赵翔，王林，彭显龙（新疆生产建设兵团农二师农科所）地膜栽培甜菜能大幅度增产已得到证实。目前这项技术已在新疆焉耆垦区推广种植。并取得了较好的经济效益和社会效益。亩产普遍在４ｔ左右，最高可达６～７ｔ／亩，为甜菜高产高糖栽培开辟了一个新...     

棉花套种小麦高产高效栽培技术

棉花套种小麦高产高效栽培技术杨振武（湖南省安乡县农业局４１５６００）棉地套种间作是南方棉区一种主要的耕作制度。合理的间套作能充分利用光能、地力、空间、时间，是实现高产高效栽培的有效途径。当前生产上应用的棉地间套作方式有许多，现将棉花与小麦的套种技术简...     

大面积甜菜高产栽培技术

大面积甜菜高产栽培技术郭益民，赵序国，刘金烁（黑龙江省北安市赵光农场）黑龙江省赵光农场１９９２年甜菜种植面积３万亩，平均亩产２．４ｔ，有６个队亩产超３ｔ，创农场历史的最高水平。其高产栽培的技术要点：１．合理轮作与耕作。选择排水良好、黑土层深厚的平岗地...     

万亩甜菜高产栽培技术

万亩甜菜高产栽培技术侯士忠，王华明（新疆农２师２４团生产科）新疆农２师２４团１９９５年种植甜菜１０３０６亩，平均单产３．８１８ｔ，其中亩产４ｔ以上的面积占甜菜总播种面积的５１．１８％。共主要栽培经验为：一、大面积推广甜菜地膜覆盖栽培技术地膜覆盖栽培甜...     

河西走廊甜菜套种孜然、小麦及胡麻的技术措施

介绍了河西走廊甜菜分别与孜然、小麦、胡麻套种的栽培技术,其种植综合经济效益比单种甜菜高400~1000元/667m2,适合大面积推广应用。     

万亩甜菜综合栽培技术的研究

为了改变黑龙江省甜菜低产低糖面貌,把已获得的科研成果,迅速变为生产力。省科委组织轻工部糖所、安达市和中国农科院甜菜所共18名技术人员,深入安达市的万宝山乡和羊草镇,进行了万亩甜菜综合栽培试验研究。经1981～1983三年的共同努力,万亩甜菜平均亩产达2,034公斤,含糖达16.3度,达到了预计的产量和含糖指标,而且经济效益显著,亩纯收入达123元。     

黄淮海棉区麦棉两熟现状与展望

一、麦棉两熟的发展概况黄淮海地区是棉产区,也是粮产区。过去在小面积上有麦棉两熟种植,一般亩产小麦100～150公斤,子棉100公斤。60年代起不少地区开始麦棉间作套种,一度发挥了增产效果。70年代麦棉间作套种面积有了一定发展,1976年麦棉两熟棉田约占棉田总面积     

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。     

芦笋枯萎病病原鉴定

对造成福建省漳州市东山县的芦笋枯萎病病原菌进行分子鉴定,以期确定病原菌的属、种名,为防治该病害寻求理论依据。试验对分离纯化的病原菌核糖体DNA的ITS区进行测序,在Genbank中搜索其同源性并构建它们的系统发育树,结果表明：引起芦笋枯萎病的病原菌是镰刀属中的尖孢镰刀菌(Fusarium oxysporum),且病原菌之间的同源性高达89%,遗传差异不显著。     

中耕方式对土壤理化特性及玉米生长发育影响研究Ⅰ.中耕方式对玉米生长发育的影响

2002～2003年在0～3次中耕条件下研究了中耕方式对玉米生长发育和产量形成的影响。结果表明,多次中耕增大了玉米倒伏率,降低了玉米最大叶面积指数、株高及各时期叶片叶绿素含量,对花粒期玉米净光合速率、气孔导度、蒸腾速率也产生一定的负面影响。少中耕有增产的趋势,并且可以降低生产成本、增加经济效益。     

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％。     

Size and frequency of occurrence of pre-roost gatherings of starlings

One hundred and fifty-six pre-roost gatherings of starlings were observed at 28 sites around a roost in west Norfolk during winter. Pre-roost gatherings occurred more frequently at individual farmyards compared with individual fields, but 82% of the sites where gatherings occurred were on fields. The size of gatherings was greater, the closer to the roost. Birds in pre-roost gatherings on fields of autumn-sown winter wheat spent most of the time feeding and had a diet composed almost exclusively of wheat seeds. Birds in gatherings on grass fields also fed intensively whereas only 31% of birds at farmyards were feeding. The implications that these results have with regard to potential damage to fields of winter wheat and around farmyards are discussed.     

12份白花泡桐材料亲缘关系的ISSR分析

以‘福桐’、‘绿桐’2个无性系与10个不同种源的白花泡桐个体为研究对象,采用ISSR分子标记对12份白花泡桐材料的亲缘关系进行研究,并利用DPSv3.01进行聚类分析。结果表明：10条引物共扩增出66条条带,其中有37条多态带,多态性比例为56.1%。根据ISSR聚类分析结果,在遗传距离为0.35时,12份白花泡桐材料可分为5类,第1类为‘福桐’无性系与河南、河北种源个体;第2类为‘绿桐’无性系与湖南、湖北、江苏种源个体;第3类为浙江、广东种源个体;第4类为江西、福建种源个体;第5类为广西种源个体。此结果     

论长白山人参主要品种类型栽种方式及其商品分类

本文论述了长白山人参主要品种类型的栽种方式、总结其规范化种植的工艺流程、对各人参品种类型栽种方式、技术要点、品种退化的主要原因及其解决措施作了详细的研讨。强调指出人参的各种栽种方式必须实施GAP标准化管理才是最好的栽种方式。重点报告了人参主产区,最新最好的栽种方式。并对人参商品分类及野山参分等质量标准中的野山参、移山参的定义提出修改意见,为提高我国人参产品质量在国际市场上的竞争能力,保持人参产业可持续发展提供科学依据。     

Mechanism of action of insecticidal secondary metabolites of plant origin

Insect pest management is facing the economic and ecological challenge worldwide due to the human and environmental hazards caused by majority of the synthetic pesticide chemicals. Identification of novel effective insecticidal compounds is essential to combat increasing resistance rates. Botanicals containing active insecticidal phytochemicals appear to be promising to address some of these problems. Therefore, there is a continuous need to explore new active molecules with different mechanisms of action. Secondary metabolites present in plants apparently function as defense (toxic), which inhibits reproduction and other processes. The phytochemical biomolecules could be used for maximizing the effectiveness and specificity in future insecticide design with specific or multiple target sites, while ensuring the economic and ecological sustainability. In this article, the current state of knowledge on phytochemical sources and insecticidal activity, their mechanism of action in insects, resistance, and promising advances made in phytochemical research are reviewed.     

蝉拟青霉疏水蛋白PChyd基因表达模式分析及敲除载体构建

为深入研究昆虫病原真菌蝉拟青霉疏水蛋白PChyd基因的功能,根据蝉拟青霉基因组信息克隆疏水蛋白PChyd基因,对该基因序列进行生物信息学分析,使用qRT-PCR技术对其在不同培养条件或阶段下的表达模式进行分析,并通过酶切酶连的方法构建了该基因的敲除载体。结果表明：PChyd基因的开放阅读框序列全长303 bp,编码100 aa,包含22 aa的信号肽序列和70 aa疏水蛋白功能区域。系统发育分析显示该基因与粗糙虫草菌亲缘关系最近。qRT-PCR结果显示PChyd基因在PDA培养的菌丝体、诱导的附着胞、诱导的芽生孢子中表达量显著高于另外2个样品,其中芽生孢子表达量最高,暗示该基因在蝉拟青霉侵染初期和在昆虫血腔中定殖阶段可能具有重要作用。凝胶电泳结果表明,成功构建了该基因的敲除载体,扩增出含有上臂、HPH、下臂的3356 bp左右的片段。本研究为进一步探究蝉拟青霉疏水蛋白PChyd基因的致病机理、生防工程菌的改造奠定了基础。