农学专业英语 2页

精品文档，仅供学习与交流，如有侵权请联系网站删除Unit11.Thebasicpartsofaplantatherootsystem,whichisbelowtheground,andtheshootsystemabove.一植株最基本组成部分是地下根系统和地上茎系统2.Ittakesin,orabsorbs,waterandmineralfromthesoilthroughtheroothairs,whicharesinglecellsnearthetipofeachroot根毛是靠近根顶端的单细胞，它可以从土壤中吸收水分和矿物质3.Inaddition,plantssuchascloverandLucerne,knownas‘legumes’havespecialbacteriawhichliveontheroots.另外，一些豆科作物，如三叶草和苜蓿，有特殊的寄生在根部的细菌4.Anotherimportantfunctionistoenablewaterandmineraltopassupfromtherootstotheleavesandflowers.另一种重要的功能是使水和矿物质从根运输到叶片和花上5.Theirmainjobistomakefoodfortheplantbytheprocessknownasphotosynthesis.它们的主要任务是光合作用为作物提供营养6.Waterfromthesoilandcarbondioxidefromtheairareconvertedintosugarsandothercarbohydrates.来自土壤中的水和来自大气中的二氧化碳被转变成糖和碳水化合物7.Thestamensproducethemalesexcells,orspermatic,whicharecarriedinthepollengrains雄蕊产生雄性细胞或是性孢子，它们被花粉粒携带.8.Thefruit,theripenedovaryoftheflower,enclosestheseedsandprotectsthemwhiletheyaredeveloping，果实，花中成熟的子房，包围着种子，当它们发育时候并保护它们9.Theseeditselfconsistsofanembryoandfoodstore种子是由胚和.胚乳构成的10.Theembryoisthepartwhichwilldevelopintoantherplantandthefoodstoreisnecessarytoprovidenourishmentfortheyoungplantwhileitisgrowing.胚是能发育成另外作物的器官，胚乳是为发育中的幼体提供必要的营养Unit21.Seedsremaindormant,orinarestingstate,iftheyarekeptcoolanddry.种子在低温和干燥条件下，处于休眠状态2.Whentheamountofmoistureandthetemperaturelevelareright,theseedsgerminateandstartgrowing.当温度和湿度适宜时，种子发芽并开始生长3.Thisisbecausewetsoilsremaincoldforalongerperiodoftimethandrier,well-drainedsoils.这是因为湿的土壤比干燥的排水好的土壤更能保持更长时间的低温4.Dormantseedsrequireverylittleoxygeninordertostayalive,butwhentheystarttogerminatetheyrequiremore.种子在休眠状态时为保持活力需要较少o2，但当它们发芽时需要较多的o25.Intheearlystagesofdevelopmenttheseedlingdependsentirelyonthefoodstoreintheseedbutassoonasthefirstleavesareproduced,itisabletomanufacturefoodforitself.发育早期，幼苗完全依靠种子中的胚乳，但是一旦第一片子叶产生，它就能为自己生产食物6.Intheprocessofpollinationthepolleniscarriedbywindorinsectsfromthestamenstothestigmaofthecarpel.传播花粉过程中，花粉被风或是昆虫从雄蕊传播，到雌蕊柱头上7.Itgerminatesonthestigmaandgrowsdownthestyleintotheovary,wherefertilizationtakesplace.它在柱头上产生并在子房中发育，进行受精Unit31.Organicmaterialoriginatesfromdeadplantsandanimalsandmaterialotherthanthisarederivedfromrocksofvariouskinds.有机质发源于死的动植物，而矿物质是与之不同的不经分解，来源于不同种类的岩石2.Theserocksarebrokendownintosmallparticlesbymechanicaldisintegrationandchemicaldecomposition.这些岩石通过物理和化学分解成小颗粒3.Inaridregionsweatheringismostlybyphysicalmeans.在干旱地区，风化主要由于物理因素4.Butinhumidregionschemicalprocessesofweatheringareequallyimportant但是在湿润的地区，风蚀的化学过程是同等重要的.5.Consequently,theinsolublemineralresiduesinthesoilshavelessresemblancetotheoriginalrocks.因此，土壤中难以溶解的残余矿物质与原始的岩石无什么类似处6.Mostofthemcontainvariousproportionsofsand,siltandclayandthesevaryingproportionsmakeupasoil’stexturalclass.土壤主要包括沙子，粉砂，粘土。。它们不同的比例构成了土壤不同的质地等级7.Theprincipleclassesinorderofincreasingfinenessofmaterialaresand,loamysand,loamy,siltloamy,siltyclayloam,clayloam,siltandclay.依照矿物质纯度顺序排列依次为沙土，壤砂土，壤土粉砂土，粘壤土，粉砂和粘土8.Thatistosay,smallersizedparticlescanreactorcombinewithwater,nutrientsandhumusmoresassilythanlargersizedparticles.就是说，小颗粒与水，营养和腐殖质比大颗粒更容易结合9.Humusfromdecomposedorganicmatterisvitaltoasoilasitmakesaheavysoillighter.来源于腐烂有机物质的腐殖质，对土壤至关重要，因为它使土壤变的更疏松Unit42.Theeasewithwhichwatersanpassthroughasoildependsontheproportionsinitofcoarseandfineparticlessuchassandandclay.水分渗入土壤的容易度依靠土壤粗细比例，例如砂土和粘土10.Anotheradvantageisthatawell-drainedsoilwillhaveenoughairforaerobicbacteriatobreakdownhumusandsoprovidefoodfortheplant.另一个优点是排水很好的土壤会有足够的空气，为好氧的细菌去分解腐殖质，然后为作物提供营养12.Ditchescanbecutatcertainintervalsbetweenthecrops.在作物之间沟渠被切割成特定的间隔16.Porousdrainagetilesmaybelaidinoronthelandandthesewillhelpdrawoffthesurpluswater.多孔排水管平放入地下或地面下，这样会有助于放掉多余水分【精品文档】第2页\n精品文档，仅供学习与交流，如有侵权请联系网站删除16.Thedistancebetweenthedrainswilldependsontheleveloftheland,thepermeabilityofthesoil,andtheamountofrainfall.排水间的距离取决于土地的平坦程度，土壤渗透性和雨量的多少22.Weshoulddistinguishbetweenthecollectionofwateranditsapplication我们应辨别水的集合和它的利用之间加以区别.23.Therearetwomainsourcesofirrigationwater:surfacewaterandgroundwater.有两种主要的灌溉水资源：地表水和地下水31.Bythiswemeantheamountofwaterwhichisneededtobringthesoiltofullcapacity.意思是需要的水的量是能使土壤达到充分的?的数量32.Italsodependsonthetypeofcrop,thestageofgrowthofthecropandtheamountwhichitwilluseatthatparticulartime.它也取决于作物的类型，作物生育时期和它在特殊时期的使用量34.Mostplantsrequirelargerquantitiesofwaterduringthelaterstagesthanintheearlierstages.大部分作物在后期比前期需要更大量的水Unit58.Finally,itmakesupfortheplantnutrientswhichhavebeenremovedbycropsorlostbyleachingandsoilerosion.最终，它弥补了作物吸收，淋溶土壤侵蚀所流失的营养14.So,theymaybegroupedasnitrogenousfertilizers,phosphaticfertilizers,potassicfertilizersandsoon.因此，它们被分为氮肥，磷肥，钾肥等15.Themostcommonlyusedfertilizerwhichcontainsnitrogenisammoniumsulphate,whichismadefromammoniaandsulphuricacid,andwhichcontains21%nitrogen使用最普遍的肥料是含氮的，主要有硫酸铵等，它由氨和硫酸组成，其中含氮量百分二十一.16.Thiselementencouragesrapidvegetativegrowthandgivesplantsahealthygreencolour.这个要素促进作物快速生长并给作物一个健康的绿色19.Phosphorousstimulatestheformationofaplant'sroot,andpromotesfruitandseedproduction.磷刺激根系形成，促进结果和种子产量21.finally,whereverhighcropyieldsareexpected,potashisusedtogetherwithnitrogenandphosphorous.最终，无论在哪高产量都是被期望的，通过k与n,p混合使用23.Thishelpplanttowithstandmechanicaldamagesuchasbrokenbranchesandtornleaves.k有助于作物抵抗机械伤害，例如残枝败叶27.Itisusuallysuppliedintheformofmuriateofpotash(potassiumchloride),whichcontains50to60%potassiumoxide(K2O)andsulphateofpotash(potassiumsulphate).它总是以k的化合物形式被使用，包括百分五十到60的k2o和k2so432.Ifasoilisveryacid,withapHvalueoflessthan5.0,limecanbeaddedtocorrectthisacidity.如果土壤极酸性，ph小于5，石灰能够改善土壤的酸性35.Nitrogen,phosphorousandpotassiumaremoreeasilyavailableinawell-limedsoilthaninanacidsoil.氮磷钾在用石灰处理的土壤中比在酸性的土壤中更容易被利用Unit61Incropproductionthecontrolofweeds,diseasesandpestsisessentialtoobtainhighyields.杂草和虫害的控制对于获得高产量是有必要的5Weedsreducecropyieldsonaccountofthefactthattheycompetewithcropsforwater.杂草使作物产量降低的原因是它与作物竞争水分，营养，光照7Mostweedsareaggressiveandinvasive,theygrowquicklyandspreadfar,andsoaredifficulttogetridof.大多数杂草是有竞争性和侵害性的，它们生长迅速，传播的远，因此很难摆脱8Onerecommendedwayoferadicatingmanypersistentweedsisfirsttoploughuptherootsandundergroundpartsoftheplant.一种值得推荐的根除多年生杂草的方法是首先？根系和作物地下部分11Weedsmayalsobekilledbymeansofchemicalswhichhavethecollectivenameofherbicides.杂草也可以被称为除草剂的化学药剂杀死17Theymustbeusedextremelycarefullyforthesimplereasonthattheywilleradicateallplantsoncontact-whichincludesthecropitself.它们在使用的时候必须相当小心，原因很简单就是它们会根除所有与之接触的植物包括作物本身18Theyareusuallyusedbeforesowingorbeforetheemergenceofthecropitself.它们总是被用于播种前或作物出土前23Micro-organismsarereproducedandspreadbyminutebodiessuchasspores,fungiandbacteria.微生物通过芽孢，真菌，细菌等微小物体进行繁殖和扩散25Itisverydifficulttokillthefungiandbacteria,ortomaketheviruswhichisinsidethehostplantinactive消灭真菌和细菌或是使寄生在寄主中不活跃的病毒不传播病毒是非常困难的.26Buttheevolutionofplantvarietieswhichcanresistdiseasehascompletelychangedmethodsofdiseasecontrol但是能够抵抗病害的作物种类的进化，已经完全改变了病害控制的方法36Onewayistousechemicalsthateasilychangeintoagasorvapour,whichenterthesoilandkilltheharmfulorganisms.一种方法是使用容易变成气体或烟雾状的化学药剂这样就能进入土壤消灭有害生物体【精品文档】第2页