农业专业英语

Lesson5AgronomicManagementPracticesAffectingTobaccoQualityNewWords&ExpressionsBuyoutn.asituationinwhichapersonorgroupgainscontrolofacompanybybuyingallofitsshares全部买下、买断Post-buyout买断后MHmaleichydrazide顺丁烯二酸酰肼，马来酰肼Alkaloidsn.anyofnumerousorganicbases(asmorphine)containingnitrogenandusuallyoxygenthatoccurespeciallyinseedplants生物碱Topv.toremoveorcutthetopof给……打顶Suckern.ashootfromthelowerpartofthestemofaplant腋芽Stalkn.alongnarrowpartofaplantsupportingoneormoreleaves,flowersorfruits柄、梗Nicotinen.apoisonousalkaloid（C10H14N2）thatisthechiefactivematerialoftobaccoandisusedasaninsecticide尼古丁Curev.topreservebydryingit晒、烘烤Maturea.fullygrownanddeveloped成熟的Hornwormn.akindofinsects天蛾幼虫Mo(u)ldn.asuperficialgrowthproducedespeciallyondampordecayingorganicmatteroronlivingorganisms霉菌Bluemo(u)ld青霉病Lay-byn.thefinaloperationinthegrowingofafieldcrop最后的田间作业Variegatedv.markedindifferentcoloredspots,lines,areasetc杂色的、斑驳的Sidedressv.toapplynutrientsononesideoftheplantroots侧施肥Nondescripta.belongingtonoparticularclassorkind无归类的;noteasilydescribed难以形容的Suckerciden.chemicalproductthatpreventssuckerfromgrowing腋芽抑制剂Contactsn.chemicalsthatkillinsectsbycontactingthemdirectly触杀剂Systemicsn.apesticidethatasusedisharmlesstotheplant,butwhenabsorbedintoitssapmakestheentireorganismtoxictopests内吸剂Versusprep.Against;incontrastto对、和……相比Primingn.pickingup采收，采摘Burleyn.athin-bodiedair-curedtobaccogrownmainlyinKentucky白肋烟TextIn2005,tobaccowillbeproducedandmarketedwithoutpricesupportforthefirsttimesince1939.Pricescheduleswillreflectanemphasisonquality,withdeepdiscountsforunripeandimmaturegrades.Inthepost-buyoutenvironment,profitabilitywillbedirectlyrelatedtothemarketingofqualitytobaccoproducedatthelowestcost.Anumberofmanagementpracticesaffecttobaccoquality.Someofthemostimportantareasfollows:在2005年，烟草将自1939年以来第一次在没有价格支持下生产和销售。价格表将反映对烟叶质量的重视，未熟等级将大幅降价。在后烟草配额买断的环境下，利润将直接与以最低成本生产的优质烟草的销售相关。很多农艺措施影响烟草的质量，最重要的一些措施有：•Nitrogenrateandtimeofapplication•ToppingandsuckercontrolwithminimalMHresidues•Harvestrateandripeness•Leafseparationbystalkposition●氮肥的施用量和施用时间●打顶和最少马来酰肼残留的腋芽控制●采收速率和成熟度●叶片分部位采收NitrogenRateandTimeofApplicationNitrogenisthemostimportantnutrientaffectingtobaccoyieldandquality.Asnitrogenrateincreases,thefollowingoccur:•Yieldincreasestoapointthendecreases.•Leafsizeincreases,butleafthicknessdecreases.•Totalalkaloids,includingnicotine,increaseandsugarsdecreaseinthecuredleaf.•Maturityandripeningaredelayed.•Curedleafdarkens.•Suckergrowthincreasesandsuckercontroldecreases.•Leafdropandleafbreakincrease.•Bluemoldismoresevere.•Hornwormandaphidpopulationsincrease.氮肥的施用量和施用时间氮素是影响烟草产量和质量的最重要的营养元素。随着氮用量的增加，将会出现以下情况：●产量增加到一定值，然后下降。●叶面积增大，但叶厚度减小。●在调制后叶片中，总生物碱、烟碱增加，糖减少。●成熟延迟。●调制后叶片变黑。●腋芽数增加，腋芽控制效果降低。●残伤增加。●霜霉病更加严重。●天蛾幼虫和蚜虫的虫口增加。Manygrowersspendconsiderabletimechoosingamongsidedresserssuchascalciumnitrate,sodiumnitrate,30percentUANliquid,and24SUANliquid.However,thedataindicatethatinthesoutheasternUnitedStatestherateandtimeofapplicationaremoreimportantthanthesidedresser.Unlessleachingoccurs,nitrogenshouldnotbeappliedafterlay-by.Lateseasonapplicationdelaysripeningandresultsinvariegated-unripegrades.许多种植者花费了相当多的时间选择侧施肥料，比如硝酸钙、硝酸钠、30％的UAN(尿素硝铵)液体肥料和24S的UAN液体肥料。然而，数据表明：在美国东南部，氮肥的施用量和施用时间比侧施肥料更重要。除非发生淋洗，氮肥不应在烟草侧施肥后施用。后期施用延迟烟叶成熟，导致杂色-未熟等级的产生。ToppingandSuckerControlToppingtobaccointhebuttonstage(soonaftertheflowerbeginstoappear)ratherthanlaterincreasesyieldandbodyifsuckersarecontrolled.Whentobaccoplantsarenottoppedforthreeweeksafterreachingthebuttonstage,yieldsarereducedby20to25poundsperacreperday,orabout1percentperacreperdaywhennormalyieldsareinthe2,000-to2,500-pounds-per-acrerange.打顶和腋芽控制如果控制腋芽，烟草在现蕾期打顶比现蕾期之后打顶能够提高产量、增加身份。如果烟株在现蕾期后三周不打顶，则每天每英亩减少产量20～25磅，或者在正常产量在每英亩2000～2500磅的范围内时每天减少l％的产量。Higheryieldsreduceper-poundproductioncostsforacreage-relatedinputssuchaschemicals,fertilizers,andsomelaborexpenses.Toppingearlyalsoimproveschemicalandphysicalqualitiesoftheleafbystimulatingrootdevelopmentandalkaloidproductionandbyreducingbuildupofinsects.高产减少了与面积相关的生产成本，如农药、肥料和一些劳动力支出。早打顶还通过刺激根系的发育、生物碱的生成以及减少害虫的危害而提高烟叶的化学和物理品质。Controlofsuckergrowthiscriticaltomaximizingyieldbecauseitallowstheplanttoconcentrateresourcesontheproductionofleavesinsteadofsuckers.Suckerscanalsointerferewithmechanicalharvestingandbecomeasignificantsourceofforeignmatterincuredleaves.Thekeytosuccessfulsuckercontrolispropertimingofsuckercideapplicationanduseofproperratesofcontactsandsystemics.抑制腋芽生长对最大限度地增产是很关键的，因为它使植株把资源集中到叶片而非腋芽的生产。腋芽也会妨碍机械采收并成为调制后烟叶中杂质的一个重要来源。成功控制腋芽生长的关键是适时施用腋芽抑制剂以及适量施用接触性和内吸性抑制剂。HarvestRateandRipenessWhenitcomestoquality,thereisnosubstituteforharvestingripetobacco.Theripeningrateisdeterminedbynitrogenuptake,rainfall,temperature,roothealth,andvariety.Thus,ripeningisgreatlyaffectedbyweatherconditionsandvariesconsiderablyfromoneseasontoanother.The2002versus2003and2004growingseasonswereatoppositeextremes.The2002seasonwasoneofthedriestseasonsonrecord,with2003and2004amongthewettest.采收速率和成熟度从烟叶品质方面考虑，没有比采收成熟烟叶更重要的了。成熟速率是由氮吸收、降雨量、温度、根系健康状况和品种所决定的。因此，成熟受气候条件影响很大，季节之间差异很大。2002生长季节与2003和2004生长季节是两个相反的极端。2002季节是历史上最干