简介：Defenceproteinsareakindofchemicaldefencecompounds.Theyplayakeyroleinplantrestrainingbioticandabioticharm.Toilluminateactivitiesofsomedefenseproteinsassociatedwithageorplantfamilyoflarch,thelarchneedleswerecollectedfromtwodifferentfamiliesofKoreanlarch,Larixolgensisandahybridlarch,L.kaempferi×L.gmelinii,respectively,andthentheactivitiesofdefenceproteinsinthoseweretestedusingaUVspectrophotometry.Theresultsshowedthattheactivitiesofprotectiveenzymesatthe16-/17-and19-year-agegroupswerehigherthanthoseattheotheragegroupsinthebothlarchspecies.Whiletheactivitiesofpolyphenoloxidase(PPO)atthe16-/17-year-agegroupandphenylalanineammonia-lyase(PAL)andproteaseinhibitorsatthe19-year-agegroupwerethehighestamongallagegroups.Then,comparedwithL.olgensis,thehybridlarchhadsignificanteffectsontheactivitiesofprotectiveenzymes.TheeffectsofplantfamilyontheactivitiesofPALandchymotrypsininhibitorweresignificantlydifferent,andthenthoseontheactivitiesofPPOwerenotsignificantlydifferent.TheeffectsofthetwofamiliesinL.olgensisontheactivitiesoftrypsininhibitor(TI)weresignificantlydifferent,whilethoseinthehybridlarchontheactivitiesofTIwerecontrary.Toconclusionsshowedthatthedifferentageandplantfamilysignificantlyaffectedtheactivitiesofdefenceproteinsintheneedlesoftwolarchspecies,andthenenhancedthelarchresistancetopests.Thesecouldplayakeyfunctioninforestrytreegeneticimprovementandmanagementinfuture.

简介：日本：据日本木材出口振兴协会《木材出口统计月报》数据，1-9月日本出口原木为73．119万m^3、锯材9．5408万岔、单板薄板63．3万m2、胶合板8．4950万m^3、纤维板6881m^3、刨花板1．1212万m^3，除纤维板外同比均有不同程度的增长。其中，出口中国的纤维板和刨花板同比有所减少，其他均为增长（见右表）。

简介：MultiplicationofElaeagnusangustifoliaL.wasexaminedinvitrosuccessivelyfromasingleshootunderthespecifiedconditionofdifferentmedia,plantgrowthregulators,pHvalueandsucroseconcentration.ItwasshowedthatMMS1wasthemostsuitablemediumonshootmultiplicationamong5mediaconcerned;BAPwasthemosteffectiveoneamongallthecytokinininvolved,BAP,KN,TDZandZT;theexpluntofthetophalf-partfromashootproducedmorenewshootsthanthatofthefoothalf-partdid;morenewshoots(>2cm)wereproducedunder3%sucrosebetweentheconcentrationswithtophalf-partexplants;shootscouldgrowwellbetweenpH4.4andpH7.0,andthebiggestnumberofshootswasproducedinpH5.6,whileinpH5.8themaximumrootingrateappeared.Asaresult,thecombinationof0.5μMBAPand0.1μMIBAonMMS1mediuminducedthemaximumshootmultiplication.Thenumberofshootamplified3timesin1month,and3^12shoots(>2cm)mightbetheoreticallymultipliedannuallyfromasingleshoot.

简介：通过电镜对拟南芥野生型及ｅｐｎ型突变体小孢子发生和发育进一步研究（此突变体的特征是花粉从游离核时期就具有多核、多沟并有分枝的花粉管），值得注意的是突变体在发育至四核花粉母细胞时期，在整个母细胞原生质膜外开始形成小孢子的外壁（与野生型晚期四分体内单倍体小孢子原生质体外形成的外壁相同），此外，在突变体小孢子发生的整个过程中也未见到正常四分体的出现。因此，设想具有两个营养核、两个生殖核的突变体的大花粉直接由非正常的四核花粉母细胞形成，突变体发生缺失的时期在前减数分裂期或减数分裂Ⅱ

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简介：InordertomaintainhigheremergenceratewithdirectseedinginShandongrockymountain,effectsofdifferentcoveringwaysonemergencerateofSophorajaponicaL.directseedingwerestudied.Theresultsshowedthatbothmulchingfilmandgrasscovercouldeffectivelyincreasethemoisturecontentofthesoilatthedepthof0-30cm,contributingtosoilmoistureconservationandtheinhibitionofsoilevaporation,whichcreatedfavorablemoistureenvironmentforthegrowthofS.japonicaseeds.Bothth...

简介：Applyingtheeconomicprinciples,thisarticlecarriesouttheassessmentofeconomicperformancesbroughtbyforestryresearchachievementthroughresearchanddiscussionontheassessmentmethodofeconomicperformancesofprovenancepopularizationofPinusmassonianaL.Thearticlealsobringsintheoptionmethodtofullydisplaythevalueofforestresearchachievement.

简介：<正>1、苹果籽不宜作砧木育苗实践证明,以苹果籽作砧木育出的苗木,生长势弱,延迟2—3年进入盛果期,且感染根腐病机率明显增大。而以海棠籽、新疆野苹果籽育出的苹果苗木,根系发达,生长势旺,抗逆性强。故在苹果育勒中,应提倡以海棠籽、新疆野苹果籽作砧木育苗,严格禁止以苹果籽作砧木育苗。

简介：Theneedforreforestationincorkoak（QuercussuberL.）areasischallengedbydifficulties.Principalamongtheseisherbivoryofyoungplants,vegetativecompetition,andslowgrowthratesofcorkoakseedlings.WeevaluatedtheearlydevelopmentofcorkoakseedlingstreatedusingtreesheltersandmulchinginnorthwesternTunisia.Wetestedthreetreesheltertreatments（non-vented,vented,andcontrol）toshieldseedlingsfromanimaldamageandfivemulchtypestocontrolcompetingvegetation（ItalianStonePine,Lentisk,combinationofItalianStonePineandLentisk（organicmulches）,gravel（inorganicmulch）andnomulch）.Attheendofthetwo-yearexperiment,shelteredseedlingswere89-99%tallerthanunshelteredseedlingsandhadhighernumbersandlengthsofshootgrowthflushes.Incontrast,bothstemdiametergrowthanddryweightbiomass（fromsamplesextractedaftertwoyears）weresignificantlyreducedinsidetreeshelters.Root-to-shootratiowasnotsignificantlydifferentinshelteredvs.unshelteredseedlings,suggestingthattreesheltersdonotadverselyaffectthisparameter.Mulchingalonedidnotfavourgrowth,butcouldbebeneficialwhencombinedwithtreeshelters.Thecombinationofventedtreesheltersandgravelmulchwasthemosteffectivetreatmentforpromotingdiameter,heightandstemvolumegrowth.

简介：Blacklocust(RobiniapseudoacaciaL.)wasthefirstNorth-AmericantreespeciesimportedtoEuropeatthebeginningoftheseventeenthcentury.Itiscommonlyplantedworldwidebecauseofitsadaptabilitytoenvironmentalstresses,itsvaluablewood,easypropagation,frequentandabundantseedproduction,excellentcoppicing,highseedlingsurvival,andrelativelyhighwoodyield.InEurope,RomaniaandHungaryhavethemosthighly-developedblacklocustgrowingtechniquesandexperiences.Asaresultofincreasinginterestinblacklocustinmanycountries,thisreviewaimstoprovideacomprehensiveoverviewofstate-of-the-artsiterequirements,propagation,improvementandmanagement(includinggrowthandyieldaswellasuseinenergyplantations).

简介：<正>职业习惯一日,上尉陪同中校检阅新兵时,问新上任的排长:“为什么把个子高、脸蛋漂亮的都排在前边,而把长得丑的矮个子排在后边呢?”“报告上尉”,排长立即向上尉行了个军礼:“我在入伍之前,是摆摊卖水果的小商贩!”

简介：<正>据报道在国外及港澳等地,人们喜爱的宠物种类繁多,除人们熟悉的蟋蟀、蝴蝶、蝈蝈外,还喜欢玩经过驯养的不同品种的蜘蛛。蜘蛛有会唱歌的、会捕鸟的、会织字母图案的等等,其身价则因功能不同而异,最高每只可卖1000港元,一般也能卖80～100港元。国内现己有人以养小蜘蛛挣大钱致富的专业户。

简介：<正>1995年春季甘肃省东乡县在果园乡、那勒寺乡、赵家乡、五家乡的沟川农田中定植以早酥梨为主的优质梨5000亩。各级领导干部亲临指挥,业务部门规划、调苗、现场把关,忙得不亦乐乎。可到当年11月底这片大规模早酥梨商品基地上的果树苗已荡然无存。

简介：ThedifferentiationprocessincludingsomaticembryogenesisindifferentGinkgoexplantsinvitroculturewerestudiedbycytologicalobservation.Theresultsareasfollows:1)twocompletecotyledonsandaembryobudwereobservedinmatureembryosandseveralsecretoryacavitivesappearedinmaturationregionofembryobuds,hypocotyls,cotyledonsandradiclesafterculturing20days;twoincompletecotyledonsandaembryobudprimordiawerefoundinlargecotyledonembryos.Theproembryooftwocells,fourcells,multi-cellular,andglobularembroyweredevelopedfromthecallusofthesmallcotyledonembryos.2)Thedifferentiationofcotyledonexplantsstartedfromepidermalcells,andgraduallyformedmeristematiccellmassinthecorticalcells,andeventuallyadventitiousbudswereobserved.3)TheadventitiousrootsofGinkgooriginatedinthecellsatthecrossofvascularcambiumandvascularrays.4)Thetypeofrootingbelongstoinductiontypebyrootprimordium.Theformedadventitiousrootswereobservedafter20days.

简介：时间1到时间2的材积净变化量可归因于进界生长量（Ⅰ）、保留木生长量（S）、死亡量（M）和伐除量（C）（比尔斯,1962）,亦即:V2-V1=I+S-M-C。在估计方程右边各生长分量时,传统的点抽样方法常常得出同左边净变化量估计值不相等的结果。本文简要阐明了产生这一问题的原因;为保留木生长量建立了一个新的估计量,从而保证了方程两边的相等性。

简介：河北省曲周县小第八村以建设高标准的生态文明园林村为载体，加快社会主义新农村的建设步伐，基本建成了“村北林下食用菌区，村东苗圃区，村南经济林区，村西农田林网区，村中空心村绿化区，庭园长绿区”的六大功能区块。

简介：胡锦涛总书记指出：“在全部公安工作中，队伍建设是根本，也是保证。”而在公安队伍建设工作中，创建学习型、服务型、廉洁型公安机关既是目标，也是时代对公安队伍正规化建设的要求。笔者认为，抓好创建学习型、服务型、廉洁型公安机关工作，首先要解决民警的思想认识问题，重点要突出实效问题，而关键在于解决“一把手”问题。

简介：我们比较了在处于Karnataka的状态种区域的三棵宽广柚木从三个种子生产区域(矿泉)和柚木(TectonagrandisL.f)的三个相应未耕过的看台(UIS)获得的子孙的词法、基因的属性，印度。一般来说，播种象种子重量，种子尺寸和种子空虚那样的词法参数在与UIS相比的矿泉是显著地优异的。种子萌芽百分比在从矿泉的种子也是更高的。在二每月的间隔测量六个月的幼苗性能被观察在在比较的三个区域中的二个的矿泉优异。尽管矿泉的子孙的基因差异根本比UIS低区域，价值中等高。当差异索引否定地每种子与水果重量，水果直径和核重量被相关时，萌芽百分比断然每种子与水果重量和核重量被相关。矿泉没有对未来种植园的基因差异的严重威胁作为中等改进的种的材料的来源证明重要。

简介：1999年4月22日至5月2日。国家林业局小流域综合治理专家组一行4人应邀对伊朗小流域综合治理情况进行了短暂考察。现将这次考察的主要情况介绍如下:一、伊朗的自然地理概况伊朗伊斯兰共和国国土面积约165万平方公里,全国人口近