膜下滴灌追施酵母浓缩液液体肥对甜菜产质量的影响

在施用底肥750 kg/hm2甜菜专用肥基础上,分别在甜菜叶丛快速增长期和块根膨大期追施0(CK)、75、150、300、450和600 L/hm2不同用量酵母浓缩液体肥及其复配液体肥(300 L/hm2),测定其对甜菜品质、块根产量和经济效益等指标的影响。结果表明:合理追施酵母浓缩液体肥及其复配液体肥可增加甜菜叶片SPAD值,提高了叶片光合性能;增加了甜菜地上叶丛及地下块根干鲜重;比CK增加块根产量3.15%～20.50%和产糖量3.85%～24.31%,提高含糖率0.12～0.59度和原汁纯度0.01～0.89个百分点,提高了甜菜块根单产和品质;合理追施酵母浓缩液体肥及其复配液体肥能够增加农民收益。综合分析表明,以底肥+300 L/hm2酵母浓缩液体肥和底肥+300 L/hm2复配液体肥效果最佳,经济效益比CK分别增加3 600元/hm2和4 203元/hm2。因此,在甜菜追肥过程中可合理追施酵母浓缩液体肥及其复配液体肥,提高甜菜单产和品质,实现资源循环利用。     

不同栽植方式对甜菜种子产量的影响

在河西走廊自然条件下多年试验结果证明:采用覆膜栽培方式可使甜菜种子产量和经济效益得到明显提高,与露地栽培方式比其增产幅度为21.6%～35.5%,平均增产率达26.8%,增加经济效益7935.2元/hm2。     

SODm叶面肥在甜菜上的应用效果

试验探讨了甜菜施用SODm叶面肥对其产量和含糖率的影响,试验结果表明:苗期喷施SODm叶面肥可以促进甜菜生长发育,提高甜菜含糖率,增产作用明显,经济效益显著,含糖率提高0.6度,块根增产13.6%。     

试谈甜菜种植的合理区划与甜菜糖厂的合理布局

目前,我国甜菜种植分散,甜菜种植区划和甜菜糖厂的布局不合理。因之,单产低、含糖低且不稳,这是我国甜菜糖业经济效益差的重要因素。合理调整种植区划、适当集中,发挥高产、高糖地区的优势,不但可以提高甜菜的单位面积产量和质量(含糖率),而且将大大减少甜菜的倒运费用。1981/1982生产期,全国大型甜菜糖厂每吨甜菜收、运、贮费用平均为28元/吨,若种植适当集中,执行过去的只付到离厂(或铁路沿线收购站)30公里运费的办法,就能使此项费用每吨降低十元,全国仅运输费用一项就能节约4000万元(1000吨/日以上大厂)。同时还能用同样多的耕地生产出更多的甜菜,增加     

齐齐哈尔甜菜含糖率与气候关系的浅析

单位面积产糖量取决于甜菜肥大直根产量及其含糖率。提高甜菜根中含糖率,乃是提高甜菜经济效益的积极有效措施。文献指出,甜菜根中含糖率受气象因素的左右很大。摸索出这些规律,趋利避害,采取相应措施,以达高产高糖之目的,进而提高经济效益。 本文仅就1965～1982年齐齐哈尔市甜菜含糖率与气象因素之间的关系,试图摸索出这一地区甜菜含糖的气象指标与测报甜菜含糖率的模式。     

全国甜菜保藏研讨会在重庆召开

为了减少甜菜保藏损失,提高糖厂经济效益,中国作物学会甜菜协会和中国农业科学院甜菜研究所于6月1日至7日在四川省重庆市召开全国甜菜保藏研讨会.出席会议有黑龙江、内蒙古、新疆、甘肃、宁夏、山西和辽宁7省(区)的甜菜科研、教学和糖厂技术管理科技人员52名。中国作物学会甜菜协会副主任.中国农业科学院甜菜研究所所长蔡葆主持了会议,并对甜菜保藏生理做了学术讲座;邀请了内蒙古赤峰市农业局高     

甜菜地膜覆盖栽培补栽纸筒苗试验

在甜菜地膜覆盖栽培田,补栽苗龄30d左右的甜菜纸筒苗,幼苗不受原地苗抑制,不缓苗,生长速度快。补栽纸筒苗12%～15%,可提高甜菜产量13.72%～19.75%;提高含糖率0.4度左右;提高产糖量13.98%～23.08%;纯利润可增加48元～110元/hm2。这项补栽保全苗技术,可普遍推广。     

吉林省甜菜地膜覆盖栽培技术

吉林省是我国甜菜的主要产区之一,常年播种面积80～90万亩,主要集中在中、西部地区。近年来,随着地膜覆盖栽培技术在甜菜生产上的应用,大幅度地提高了产量。据连续几年的试验和示范,可比直播甜菜出苗期提前7～10天,保苗率提高20％以上,块根膨大和糖分积累期延长10～15天,使亩产达2.5～3.0吨,比直播增产1.5～2.0吨,扣除增加的生产费,纯增收95～140元。是保全苗、促壮苗、大幅度提高甜菜单产和经济效益的有效措施。     

甜菜在海南冬种试验研究

连续４ 年在海南岛进行的甜菜冬季栽培试验结果证明,甜菜在具有热带气候的海南冬种是成功的,不仅长势好,病虫害也不严重。参试的３ 个甜菜品种根产量差异不显著,其中“丰抗３０９”品种块根产量４７．２５ｔ／ｈｍ２ ,含糖率１５．５２ 度。从９ 月３０ 日～１１ 月２０ 日６ 个播期处理的根产量差异显著,播期早、生育期长的产量高。试验认为,甜菜在海南冬种的最佳播期是９ 月３０ 日～１０ 月１０ 日,最佳收获期是３ 月２０ 日前后。因上茬作物晚收而不能及时播种时,采取育苗移栽,其产量不受影响     

禾本卡克防治甜菜褐斑病效果的研究

甜菜生育期褐斑病罹病率达5%～10%时,喷洒1次含三苯基醋酸锡20%的禾本卡克15kg/hm2兑水600kg/hm2,比对照(喷洒清水)提高块根产量25.0%,提高含糖率1.5度,增加产糖量39.8%;经济效益显著,投入产出比达1:28.     

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。     

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.     

农杆菌注射法瞬时转化荔枝果实组织的研究

为了寻找一种高效的荔枝果实瞬时基因表达方法,本研究以荔枝品种‘新球蜜荔’（Litchi chinensis Sonn. var. ‘Xinqiumili’）为试材,利用农杆菌注射法对荔枝果实组织进行转化,研究了果实发育时期、菌株种类、注射部位、取样时间、菌液浓度等对转化效率的影响。结果表明：选择果肉已完全包裹种子的Ⅱb期果实进行连体注射,在果柄、果皮、种子、果肉分别注入OD₆₀₀值为2.4的农杆菌菌株GV3101,4 d后取样进行检测,4个组织的GUS染色率较高。本研究成功建立了适用于荔枝果实的基因瞬时表达系统,为今后快速鉴定荔枝果实相关基因功能提供了基础。     

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。     

《生物安全法》实施背景下基因编辑技术的安全评价与监管

2020年10月17日,《中华人民共和国生物安全法》(以下简称《生物安全法》)通过全国人大常委会的审议,自2021年4月15日起施行.生物技术的研究与应用安全是《生物安全法》涉及的主要内容之一,基因编辑作为近几年生物技术领域的研究热点,其安全性评价和监管备受关注.本文概述了基因编辑技术的应用现状,比较了不同国家对基因编...     

波罗蜜叶片突变体叶绿素含量测定和超微结构观察

波罗蜜（Artocarpus heterophyllus）是一种热带果树,至今对其突变体的研究少有报道。本研究以波罗蜜叶片为试验材料,探究其叶片出现白化和返绿现象的可能原因。（1）用分光光度计法、比色法测定波罗蜜叶片突变体和正常绿叶的叶绿素及叶绿素前体物质含量;（2）用叶绿素酶Elisa试剂盒测定叶绿素酶活性;（3）用透射电子显微镜对叶绿体的超微形态结构进行观察。研究结果表明：（1）不同叶色所产生的叶绿素a含量、叶绿素b含量、叶绿素总含量、类胡萝卜素含量均存在显著差异;（2）波罗蜜叶片突变体和正常绿叶的叶绿素合成前体物质含量之间并没有出现显著性差异;（3）对波罗蜜叶片的叶绿素酶活性进行测定时,发现其活性出现显著差异,但对其叶绿素含量的差异性并没有产生较大影响;（4）观察波罗蜜叶片内叶绿体超微形态结构时,发现正常绿叶的叶绿体形态完好且数量较多,白化叶和返绿叶的叶绿体内部结构存在缺陷,其原因是叶绿体基粒构建阶段受阻;基于测定波罗蜜叶片中的叶绿素、叶绿素前体物质含量和叶绿素酶活性,并观察波罗蜜叶片内叶绿体的超微形态结构,对得到的数据结果进行比较分析。本研究推测是在叶绿素合成阶段,原脱植基叶绿素合成叶绿素时受阻及叶绿体发不良导致波罗蜜出现白化和返绿现象,为今后进一步综合研究波罗蜜突变体提供理论依据。     

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.