{"name":"烟草栽培技术员题库","level":"五级 / 四级 / 三级 / 二级 / 一级","org":"烟草行业职业技能鉴定机构","count":300,"questions":[{"id":1,"type":"single","stem":"漂浮育苗播种后，营养池水面覆盖的聚乙烯薄膜主要作用是防止水分蒸发和","options":["提高池水温度","增加池水溶氧","降低池水盐度","抑制藻类繁殖"],"answer":[0],"explanation":"知识点为漂浮育苗池膜功能。覆盖薄膜可减少蒸发并保温促萌发，故正确项为提高池水温度；增加溶氧主要靠通气，非覆膜作用；池水盐度与覆膜无关；抑藻主要靠遮光或药剂，薄膜透光反而利于藻类，故其余项错误。","tier":"基础"},{"id":2,"type":"single","stem":"烟草移栽时，井窖式移栽的关键操作是使烟苗茎秆大部分埋入土中，其直接目的是","options":["促进不定根发生","减少病毒病侵染","提高叶片含钾量","加快花序分化"],"answer":[0],"explanation":"知识点为井窖式移栽促根原理。深栽使茎秆接触湿润土壤，诱发不定根，故正确项为促进不定根发生；减少病毒病主要靠防蚜和卫生操作，非深栽直接目的；含钾量由施肥和品种决定；花序分化受温度和营养调控，与深栽无直接因果关系，故其余项错误。","tier":"进阶"},{"id":3,"type":"single","stem":"烟草团棵期田间管理中进行中耕培土，其主要作用是促进根系下扎和","options":["增强植株抗倒伏能力","降低烟叶烟碱含量","加速花芽提前分化","减少上部叶开片"],"answer":[0],"explanation":"知识点为团棵期中耕培土作用。培土使茎基部生根并稳固植株，故正确项为增强抗倒伏能力；烟碱含量主要由打顶和氮素调控；花芽分化受光温影响；上部叶开片与水分和营养有关，均非培土直接作用，故其余项错误。","tier":"基础"},{"id":4,"type":"single","stem":"烟草黑胫病在田间常从茎基部开始发病，防治该病时最应优先采取的措施是","options":["选用抗病品种并轮作","喷施叶面钾肥","增加打顶次数","提高移栽密度"],"answer":[0],"explanation":"知识点为黑胫病综合防治。该病为土传病害，抗病品种和轮作可降低菌源，故正确项为选用抗病品种并轮作；叶面钾肥只能辅助抗性，不能控病；打顶次数与病害无关；提高密度会加重湿度利于发病，故其余项错误。","tier":"进阶"},{"id":5,"type":"single","stem":"烟草打顶后，腋芽容易萌发消耗养分，抹杈应在腋芽长到多长时进行较为适宜","options":["3～5厘米","10～15厘米","20～25厘米","30厘米以上"],"answer":[0],"explanation":"知识点为打顶后抹杈时机。腋芽3～5厘米时抹除伤口小、养分消耗少，故正确项为3～5厘米；10～15厘米已消耗较多养分且伤口大；20厘米以上和30厘米以上更晚，影响产量和品质，故其余项错误。","tier":"基础"},{"id":6,"type":"single","stem":"烤烟成熟采收时，判断下部叶成熟的主要外观特征是","options":["叶色由绿转黄绿且叶尖下垂","叶面出现大量成熟斑","叶片变厚且茸毛增多","主脉变白且叶片脆硬"],"answer":[0],"explanation":"知识点为下部叶成熟特征。下部叶成熟时叶色转黄绿、叶尖下垂，故正确项为叶色由绿转黄绿且叶尖下垂；大量成熟斑多见于中上部叶；叶片变厚茸毛增多是未熟表现；主脉变白脆硬为过熟或病态，故其余项错误。","tier":"基础"},{"id":7,"type":"single","stem":"烟草苗床期遇到低温阴雨，为防止烟苗徒长，下列管理措施最恰当的是","options":["适当控水并增加通风见光","加盖草帘保温并多浇水","密闭棚膜提高湿度","增施速效氮肥促苗"],"answer":[0],"explanation":"知识点为苗床温光水调控。低温阴雨时控水通风见光可抑制徒长，故正确项为适当控水并增加通风见光；加盖草帘多浇水会加重徒长；密闭高湿利于病害和徒长；增施氮肥更促徒长，故其余项错误。","tier":"挑战"},{"id":8,"type":"single","stem":"烟草移栽后遇到持续干旱，烟苗出现萎蔫，此时正确的补水方式是","options":["小水勤浇并结合覆盖保墒","一次大量漫灌淹没垄顶","等降雨后统一补浇","只喷叶面水不浇根"],"answer":[0],"explanation":"知识点为移栽后水分管理。小水勤浇配合覆盖可保墒且不伤根，故正确项为小水勤浇并结合覆盖保墒；大量漫灌易烂根和流失养分；等雨可能延误成活；只喷叶面水不能满足根系需求，故其余项错误。","tier":"挑战"},{"id":9,"type":"single","stem":"某烟田发现部分烟株叶片呈花叶、皱缩且植株矮化，田间蚜虫较多，最可能的病害及处置是","options":["病毒病，及时拔除病株并防治蚜虫","黑胫病，灌根用药并培土","赤星病，摘除病叶并喷药","青枯病，排水并撒石灰"],"answer":[0],"explanation":"知识点为病毒病症状与传播。花叶皱缩矮化伴蚜虫多符合病毒病，应拔除病株并防蚜，故正确项为病毒病及时拔除病株并防治蚜虫；黑胫病为茎基黑腐；赤星病为叶斑；青枯病为萎蔫青枯，症状不符，故其余项错误。","tier":"挑战"},{"id":10,"type":"single","stem":"烟农在烟株旺长期一次性重施氮肥，随后烟叶贪青晚熟、上部叶开片差，正确的补救措施是","options":["控水控氮并叶面补磷钾","再追一次氮肥促生长","立即打顶并增施氮肥","深中耕断根并多浇水"],"answer":[0],"explanation":"知识点为旺长贪青调控。控水控氮并补磷钾可促成熟，故正确项为控水控氮并叶面补磷钾；再追氮肥加重贪青；打顶后增氮仍贪青；深中耕多水会促旺长，故其余项错误。","tier":"进阶"},{"id":11,"type":"single","stem":"烟草漂浮育苗中，播种后盖种用的基质厚度通常控制在","options":["2至3毫米","8至10毫米","15至20毫米","25至30毫米"],"answer":[0],"explanation":"知识点为漂浮育苗播种后盖种厚度。盖种过厚会阻碍出苗，2至3毫米既能保湿又不压苗，故正确。8至10毫米过厚，出苗顶土困难；15至20毫米严重过厚，基本不出苗；25至30毫米属于育苗盘装填基质厚度概念，不是盖种厚度。","tier":"基础"},{"id":12,"type":"single","stem":"烟草移栽时采用膜下小苗移栽，栽后掏苗封口的最佳时机是","options":["烟苗顶膜后及时掏出并封严膜口","烟苗长到团棵期再统一掏苗","烟苗顶膜后先不掏，等膜内温度升高后再掏","烟苗顶膜后只把膜划破不封口"],"answer":[0],"explanation":"知识点为膜下小苗移栽掏苗封口时机。烟苗顶膜后及时掏出并用细土封严膜口，可防高温灼苗并保住膜内温湿度，故正确。团棵期再掏苗会使烟苗在膜内受灼或徒长；等膜内温度升高后再掏会加重灼苗；只划破不封口会跑墒跑温并造成膜口进风揭膜。","tier":"基础"},{"id":13,"type":"single","stem":"烟草苗床期出现烟苗茎叶徒长、叶色淡绿、根系较弱的异常苗，最可能的原因是","options":["苗床氮肥偏多且光照不足","苗床磷钾肥偏多且光照充足","苗床水分偏少且通风过强","苗床温度偏低且昼夜温差大"],"answer":[0],"explanation":"知识点为苗床徒长苗的成因。氮肥偏多配合光照不足，烟苗会茎叶徒长、叶色淡绿、根系弱，故正确。磷钾肥偏多且光照充足会使苗矮壮；水分偏少且通风过强会使苗矮小老化；温度偏低且温差大会使苗生长缓慢、叶色偏深。","tier":"进阶"},{"id":14,"type":"single","stem":"烟草大田移栽后遭遇连续阴雨，田间出现烟苗发黄、根系发黑、拔起有腐臭味，最可能的病害是","options":["烟草黑胫病","烟草普通花叶病","烟草赤星病","烟草气候斑点病"],"answer":[0],"explanation":"知识点为黑胫病症状识别。连阴雨后烟苗发黄、根系发黑、拔起有腐臭味是黑胫病典型症状，故正确。普通花叶病表现为花叶、皱缩，不烂根；赤星病为叶片褐色病斑；气候斑点病为叶面斑点，均不引起根系腐臭。","tier":"进阶"},{"id":15,"type":"single","stem":"烟草打顶后为控制腋芽生长，抹杈应掌握的原则是","options":["腋芽长到3至5厘米时抹除，并配合抑芽剂","腋芽长到20厘米以上再一次性抹除","腋芽刚露头就用手反复触摸抹掉","腋芽长到开花后再连同花蕾一起抹除"],"answer":[0],"explanation":"知识点为打顶后抹杈技术。腋芽3至5厘米时抹除省工且伤口小，配合抑芽剂可控制再生，故正确。长到20厘米以上再抹消耗养分多且伤口大；刚露头反复触摸易传染病害且抹不净；开花后再抹已消耗大量养分。","tier":"进阶"},{"id":16,"type":"single","stem":"烟草漂浮育苗池水pH值适宜范围是","options":["5.5至6.5","7.5至8.5","8.5至9.5","3.0至4.0"],"answer":[0],"explanation":"知识点为漂浮育苗池水pH管理。烟苗适宜微酸性环境，池水pH5.5至6.5利于养分吸收和抑制部分病害，故正确。7.5至8.5偏碱，易诱发缺铁黄化；8.5至9.5碱性过强，烟苗生长受阻；3.0至4.0过酸，会伤根。","tier":"基础"},{"id":17,"type":"single","stem":"烟草地膜覆盖栽培中，若盖膜时膜面与畦面贴得不紧、膜内空隙大，最容易出现的后果是","options":["膜内杂草旺长且烟苗易受高温灼伤","膜内温度偏低且保水效果增强","膜内湿度下降且烟苗根系深扎","膜内二氧化碳积累且烟苗徒长"],"answer":[0],"explanation":"知识点为地膜覆盖质量要求。膜面与畦面贴不紧、空隙大，膜内易长草且热空气聚集灼苗，故正确。膜内温度不会因此偏低，保水效果反而变差；膜内湿度不会下降；膜内二氧化碳积累与贴膜松紧无直接对应关系。","tier":"进阶"},{"id":18,"type":"single","stem":"烟草移栽前进行炼苗的主要目的是","options":["提高烟苗抗逆性，促进栽后还苗成活","降低烟苗含水量，使叶片变薄","抑制烟苗根系生长，便于拔苗","使烟苗叶色变淡，减少氮素吸收"],"answer":[0],"explanation":"知识点为移栽前炼苗的作用。炼苗可增强烟苗抗逆性、促进栽后还苗成活，故正确。炼苗会使叶片增厚而不是变薄；会促进根系健壮而不是抑制；叶色变化不是炼苗目的。","tier":"基础"},{"id":19,"type":"single","stem":"烟草大田期发现烟株下部叶片出现水渍状暗绿色病斑，迅速扩展并沿叶柄蔓延，湿度大时病部产生白色霉层，应首先考虑","options":["烟草猝倒病","烟草黑胫病","烟草青枯病","烟草野火病"],"answer":[1],"explanation":"知识点为黑胫病田间症状。下部叶片水渍状暗绿病斑、沿叶柄蔓延、湿度大时白色霉层是黑胫病典型表现，故正确。猝倒病多发生在苗期茎基部；青枯病表现为萎蔫和茎内菌脓；野火病为叶面黄晕病斑，均不符。","tier":"挑战"},{"id":20,"type":"single","stem":"烟草蚜虫防治中，利用银灰色地膜驱避蚜虫的原理是","options":["蚜虫对银灰色有趋避反应","银灰色地膜能释放杀虫气体","银灰色地膜可提高地温杀死蚜虫","银灰色地膜能反射紫外线杀灭蚜虫"],"answer":[0],"explanation":"知识点为蚜虫物理防治。蚜虫对银灰色有趋避反应，铺银灰膜可减少蚜虫迁入，故正确。银灰膜不释放杀虫气体；提高地温不能直接杀死蚜虫；反射紫外线也不能杀灭蚜虫。","tier":"基础"},{"id":21,"type":"single","stem":"烟草成熟采收时，判断下部叶适熟的标准是","options":["叶面出现成熟斑，主脉变白，叶尖下垂","叶片全绿，主脉青绿，叶尖上翘","叶片深绿，叶面光滑，主脉粗硬","叶片黄绿，主脉青白，叶尖平展"],"answer":[0],"explanation":"知识点为下部叶成熟采收标准。下部叶适熟时叶面出现成熟斑、主脉变白、叶尖下垂，故正确。全绿主脉青绿为未熟；深绿光滑主脉粗硬为未熟；黄绿主脉青白叶尖平展介于未熟与适熟之间，不是下部叶适熟标准。","tier":"基础"},{"id":22,"type":"single","stem":"漂浮育苗播种后覆盖基质厚度通常控制在多少，既利于出苗又可减少带壳出土","options":["2至4毫米","8至10毫米","12至15毫米","18至20毫米"],"answer":[0],"explanation":"知识点为漂浮育苗播种后基质覆盖厚度。覆盖2至4毫米可保湿透光、减少带壳苗；8至10毫米过厚抑制出苗；12至15毫米出苗困难；18至20毫米基本无法正常出苗。","tier":"基础"},{"id":23,"type":"single","stem":"烟草移栽时采用地膜覆盖，其增温保墒效果最明显的土层深度是","options":["0至5厘米","10至15厘米","20至25厘米","30至35厘米"],"answer":[0],"explanation":"知识点为地膜覆盖的增温保墒机理。地膜主要提高0至5厘米表层土温并减少蒸发；10至15厘米增温已明显减弱；20至25厘米受地膜影响小；30至35厘米基本不受地膜覆盖影响。","tier":"基础"},{"id":24,"type":"single","stem":"烤烟打顶后及时抹杈的主要目的是","options":["减少腋芽消耗养分","促进根系向下深扎","降低叶片含水量","增加烟株节间长度"],"answer":[0],"explanation":"知识点为打顶抹杈的作用。抹杈可减少腋芽生长消耗光合产物，使养分向叶片转移；促进根系深扎主要靠中耕蹲苗；降低叶片含水量与抹杈无直接关系；增加节间长度是氮肥偏多和密度过大表现。","tier":"基础"},{"id":25,"type":"single","stem":"烟田发现烟蚜数量上升，释放烟蚜茧蜂进行生物防治的适宜时期是","options":["烟蚜发生初期","烟蚜盛发后期","烟叶采收结束后","烟株现蕾打顶后"],"answer":[0],"explanation":"知识点为烟蚜茧蜂释放时机。烟蚜发生初期释放，蜂蚜比合理，寄生效果好；盛发后期蚜量过大，茧蜂难以控制；采收结束后无寄主；现蕾打顶后释放与防治目标时期不匹配。","tier":"挑战"},{"id":26,"type":"single","stem":"烟草育苗盘消毒后使用前，正确的做法是","options":["用清水冲洗残留消毒液并晾干","直接带药液播种以免再次感染","用消毒液浸泡后立即装基质","放在阳光下暴晒后带药使用"],"answer":[0],"explanation":"知识点为育苗盘消毒后处理。消毒后必须清水冲洗残留药液并晾干，避免药害；带药播种易伤芽；浸泡后立即装基质药液浓度高；暴晒后带药仍可能产生药害。","tier":"进阶"},{"id":27,"type":"single","stem":"烟田施用钾肥时，为提高钾的利用率，较合理的做法是","options":["分次追施并与有机肥配合","一次性撒施于地表","在雨后大水漫灌时冲施","与石灰同时大量施用"],"answer":[0],"explanation":"知识点为钾肥施用技术。分次追施并与有机肥配合可减少钾固定和流失；地表撒施易流失；大水漫灌冲施会淋失；与石灰大量同施会因钙离子竞争影响钾吸收。","tier":"基础"},{"id":28,"type":"single","stem":"地膜覆盖烟田在团棵期揭膜的主要依据是","options":["膜内温度过高且烟株需培土","膜内温度偏低需继续保温","烟株尚未进入旺长期","土壤湿度已经达到饱和"],"answer":[0],"explanation":"知识点为地膜烟揭膜时机。团棵期揭膜多因膜内温度过高、烟株需要培土追肥；温度偏低应继续覆盖；未进旺长期不是揭膜依据；湿度饱和不是揭膜的主要判断标准。","tier":"基础"},{"id":29,"type":"single","stem":"烟草苗床期发现烟苗徒长，下列管理措施最恰当的是","options":["降低苗床温度并适当控水","增施氮肥促进叶片展开","提高苗床湿度并遮阴","增加播种密度以互相遮光"],"answer":[0],"explanation":"知识点为苗床期徒长调控。降低温度并适当控水可抑制徒长；增施氮肥会加重徒长；提高湿度遮阴更利于徒长；增加密度会加剧竞争和徒长。","tier":"挑战"},{"id":30,"type":"single","stem":"烟田防治烟青虫时，在幼虫三龄前施药效果较好的主要原因是","options":["幼虫体壁薄且取食量小","幼虫已进入烟株顶端","成虫抗药性最强","卵壳能阻止药剂进入"],"answer":[0],"explanation":"知识点为烟青虫防治适期。三龄前幼虫体壁薄、取食量小、抗药性弱，防治效果好；进入顶端不是主要原因；成虫抗药性与幼虫施药无关；卵壳阻止药剂不是三龄前施药的原因。","tier":"基础"},{"id":31,"type":"single","stem":"漂浮育苗播种后，营养池水面应保持的深度通常是","options":["1～2厘米","5～10厘米","15～20厘米","25～30厘米"],"answer":[1],"explanation":"知识点为漂浮育苗水层管理。漂浮盘漂浮需要足够水深，5～10厘米可保证盘体浮起且基质能吸水，又不至于水深过大导致水温波动剧烈。1～2厘米过浅，盘体易触底、基质吸水不足；15～20厘米和25～30厘米过深，水温变化大且操作不便、浪费营养液。","tier":"基础"},{"id":32,"type":"single","stem":"烟草移栽时采用地膜覆盖，其保墒增温效果主要发生在烟株生长的","options":["还苗期","团棵期","现蕾期","成熟期"],"answer":[0],"explanation":"知识点为地膜覆盖的时期效应。地膜在移栽后还苗期能提高地温、减少水分蒸发，促进还苗成活。团棵期后烟株封行、地温已升高，增温保墒作用减弱；现蕾期和成熟期烟株较大，地膜主要影响已不明显。","tier":"挑战"},{"id":33,"type":"single","stem":"烟草打顶后，为促进上部叶开片和成熟，常采用的措施是","options":["及时抹杈并配合抑芽剂","深中耕断根控长","增施速效氮肥促长","灌大水促叶片伸展"],"answer":[0],"explanation":"知识点为打顶后田间管理。打顶后腋芽易萌发，需及时抹杈或用抑芽剂，使养分集中供给叶片。深中耕断根会伤根减产；增施速效氮肥会导致贪青晚熟；灌大水易造成渍害和养分流失。","tier":"基础"},{"id":34,"type":"single","stem":"烟草苗床期发现烟苗茎基部缢缩、倒伏，湿度大时病部可见白色棉絮状霉层，最可能的是","options":["猝倒病","黑胫病","赤星病","花叶病"],"answer":[0],"explanation":"知识点为苗期病害识别。猝倒病典型症状是茎基部缢缩倒伏，潮湿时病部产生白色棉絮状霉层。黑胫病多发生在成株茎基部，呈黑褐色坏死；赤星病主要为害叶片；花叶病为病毒病，表现花叶症状。","tier":"挑战"},{"id":35,"type":"single","stem":"烟田发现烟蚜危害，采用释放瓢虫进行防治，这种防治方法属于","options":["生物防治","物理防治","化学防治","农业防治"],"answer":[0],"explanation":"知识点为病虫害防治方法分类。释放瓢虫等天敌属于生物防治。物理防治如黄板诱杀；化学防治如喷施药剂；农业防治如轮作、清洁田园。","tier":"挑战"},{"id":36,"type":"single","stem":"烟草团棵期追肥，若氮肥用量过大，最可能出现的后果是","options":["烟株徒长、叶片贪青晚熟","烟株矮小、叶片数减少","烟叶成熟提前、身份变薄","烟株抗病性明显增强"],"answer":[0],"explanation":"知识点为氮肥用量对烟株的影响。团棵期氮肥过量会导致烟株徒长，叶片贪青晚熟，影响烟叶品质。氮肥不足才会出现矮小、叶片数少；氮肥过量不会使成熟提前或抗病性明显增强。","tier":"进阶"},{"id":37,"type":"single","stem":"烟草黑胫病在田间传播的主要途径是","options":["雨水和灌溉水","气流远距离传播","种子带菌传播","昆虫媒介传播"],"answer":[0],"explanation":"知识点为黑胫病传播途径。黑胫病病菌主要通过雨水、灌溉水在田间传播，也可随病残体传播。气流远距离传播多见于白粉病等；种子带菌和昆虫传播不是黑胫病主要途径。","tier":"基础"},{"id":38,"type":"single","stem":"烤烟移栽时，若土壤墒情不足，正确的做法是","options":["先浇足定根水再覆土封穴","深栽不浇水等雨","减少移栽密度不浇水","推迟移栽不浇水"],"answer":[0],"explanation":"知识点为移栽保苗技术。墒情不足时应先浇足定根水，再覆土封穴，保证烟苗成活。深栽不浇水、减少密度不浇水、推迟移栽不浇水都会影响还苗成活。","tier":"进阶"},{"id":39,"type":"single","stem":"烟草苗床管理中，为防止烟苗徒长，通常采取的措施是","options":["适当通风降温和控制浇水","密闭苗床提高温度","增加氮肥施用次数","保持苗床土壤积水"],"answer":[0],"explanation":"知识点为苗床温湿度管理。适当通风降温、控制浇水可防止烟苗徒长。密闭提温、增施氮肥、保持积水都会促进徒长或引发病害。","tier":"进阶"},{"id":40,"type":"single","stem":"烟草漂浮育苗中，播种后覆盖基质厚度通常应控制在","options":["2～3毫米","5～8毫米","10～12毫米","15～20毫米"],"answer":[0],"explanation":"知识点为漂浮育苗播种覆土厚度。覆土过厚会阻碍出苗，过薄则种子裸露、保湿差，通常覆2～3毫米。5～8毫米偏厚，易造成出苗延迟；10～12毫米和15～20毫米过厚，出苗困难。","tier":"基础"},{"id":41,"type":"single","stem":"烟草移栽时，井窖式移栽与传统垄栽相比，其主要优势是","options":["栽后烟苗处于较深窖内，保温保湿利于还苗","栽后烟株根系分布更浅便于集中施肥","栽后烟苗叶片直接接触地膜加速生长","栽后不需浇定根水依靠窖内湿土"],"answer":[0],"explanation":"知识点为井窖式移栽原理。井窖内温度湿度较稳定，利于还苗。根系分布更浅说法与深栽相反；叶片接触地膜易灼伤；定根水仍需浇，不能依赖窖内土。","tier":"进阶"},{"id":42,"type":"single","stem":"烟草苗床期出现烟苗茎叶徒长、叶色淡绿，最可能的原因是","options":["苗床氮肥偏多且光照不足","苗床磷钾肥偏多且温度偏低","苗床水分偏少且通风过强","苗床基质偏酸且播种过深"],"answer":[0],"explanation":"徒长伴叶色淡多因氮多、光照弱、温度偏高。磷钾偏多不会徒长；水分少通风强会矮小；基质偏酸播种过深影响出苗而非徒长。","tier":"进阶"},{"id":43,"type":"single","stem":"烤烟大田期发现烟株中下部叶片出现水渍状暗绿斑并迅速扩展腐烂，田间湿度大，最可能是","options":["烟草黑胫病","烟草赤星病","烟草普通花叶病","烟草野火病"],"answer":[0],"explanation":"黑胫病典型为茎基部水渍状黑斑、叶片水渍状腐烂，高湿扩展快。赤星病为褐色圆斑具轮纹；花叶病为花叶皱缩；野火病为黄晕褐斑。","tier":"挑战"},{"id":44,"type":"single","stem":"烟草打顶后，为促进上部叶开片和成熟，通常采取的措施是","options":["及时抹杈并适当追施钾肥","保留全部腋芽增加光合面积","打顶后立即大量灌水促长","打顶后停止一切田间操作"],"answer":[0],"explanation":"打顶后腋芽消耗养分，需抹杈，配施钾肥促上部叶开片。保留腋芽争养分；大量灌水易贪青；停止操作不利成熟。","tier":"进阶"},{"id":45,"type":"single","stem":"烟草育苗盘消毒常用方法中，对病毒类病原较有效的是","options":["用福尔马林溶液浸泡后清水冲洗","用清水浸泡后阳光下晾晒","用草木灰涂抹盘面后播种","用干热风吹扫盘面后使用"],"answer":[0],"explanation":"福尔马林可灭活多种病毒和真菌。清水浸泡晾晒、草木灰涂抹、干热风吹扫均不能有效灭活病毒。","tier":"进阶"},{"id":46,"type":"single","stem":"烟田发现烟蚜数量上升，为减少病毒病传播，最合理的防治策略是","options":["尽早用药控制蚜量并清除田边杂草","等蚜量很大时再集中喷药","只喷烟株上部叶片即可","用黄板诱杀代替所有药剂"],"answer":[0],"explanation":"蚜虫是病毒传播媒介，应早防、清除越冬寄主。等量大再防已传播病毒；只喷上部不全面；黄板可辅助但不能完全替代。","tier":"挑战"},{"id":47,"type":"single","stem":"烟草移栽前炼苗的主要目的是","options":["提高烟苗抗逆性，促进栽后还苗","增加烟苗高度便于移栽","使烟苗叶色变深提高卖相","减少烟苗水分便于运输"],"answer":[0],"explanation":"炼苗通过控水控温通风增强抗逆性。增加高度、变深、减少水分均非目的，反而可能伤苗。","tier":"基础"},{"id":48,"type":"single","stem":"某烟农在烟株团棵期发现部分烟株心叶发黄、生长迟缓，土壤pH偏低，最可能缺乏的元素是","options":["钼","氮","钾","氯"],"answer":[0],"explanation":"酸性土壤钼有效性低，缺钼表现为心叶发黄、生长受阻。缺氮全株黄；缺钾叶缘焦枯；缺氯较少见且症状不同。","tier":"挑战"},{"id":49,"type":"single","stem":"烟草漂浮育苗中，播种后覆盖池膜保温保湿，当出苗率达到多少时，应及时揭去池膜以防高温烧苗？","options":["30%左右","50%左右","80%左右","95%以上"],"answer":[2],"explanation":"知识点：漂浮育苗出苗期池膜管理。出苗率达到80%左右时，膜内温度晴天中午可超过40℃，必须及时揭膜通风降温，否则幼芽易灼伤。30%和50%出苗时揭膜过早，苗床保湿保温不足，出苗不齐；95%以上时已接近全苗，此时揭膜已偏晚，高温烧苗风险已经发生。","tier":"进阶"},{"id":50,"type":"multi","stem":"烟草大田移栽后遭遇连续降雨，烟株出现叶片发黄、根系变褐、生长停滞，下列处置措施中恰当的有哪些？","options":["及时疏通垄沟和腰沟排除田间积水","趁土壤湿润追施速效氮肥促进恢复","中耕松土改善土壤通气性","拔除病株并带出田外集中处理","喷施广谱杀菌剂后立即覆盖地膜保温"],"answer":[0,2,3],"explanation":"知识点：涝渍后烟田管理。及时排涝、中耕松土、拔除病株是正确处置。趁湿追施速效氮肥会加重根系负担并流失，且涝后根吸收能力弱，不宜立即追肥；喷杀菌剂后覆膜会进一步阻碍土壤通气并提高膜内湿度，不利于根系恢复。","tier":"挑战"},{"id":51,"type":"single","stem":"漂浮育苗播种后，营养池水面与育苗盘基质表面应保持的初始距离是","options":["0.5～1厘米","2～3厘米","5～8厘米","10～12厘米"],"answer":[0],"explanation":"知识点为漂浮育苗的水位管理。播种后盘内基质吸水后表面应略高于水面0.5～1厘米，避免种子被水淹没。2～3厘米距离过远导致基质吸水不足；5～8厘米和10～12厘米距离过大，基质无法通过毛细作用吸足水分。","tier":"基础"},{"id":52,"type":"single","stem":"烟草苗床期遇到连续阴雨、光照不足时，防止烟苗徒长最应优先采取的棚内管理措施是","options":["加大通风排湿并适当降低苗床温度","增加浇水次数保持基质湿润","密闭棚膜提高棚内温度","喷施高浓度氮肥促进生长"],"answer":[0],"explanation":"知识点为苗床期温湿度调控。阴雨弱光下烟苗易徒长，应通风排湿并降温抑制伸长。增加浇水会加重徒长和病害；密闭棚膜提高温度更利于徒长；高浓度氮肥会加剧地上部旺长。","tier":"挑战"},{"id":53,"type":"single","stem":"烟田起垄时，垄体高度和垄距的确定主要依据","options":["当地降雨量、土壤质地和品种特性","烟农个人习惯和地块形状","烟苗移栽时的天气状况","烤房容量和烘烤进度"],"answer":[0],"explanation":"知识点为起垄规格的确定依据。垄高垄距需综合考虑降雨、土壤排水性和品种株型。个人习惯、移栽天气、烤房容量均不是确定垄体规格的主要依据。","tier":"进阶"},{"id":54,"type":"single","stem":"烟草大田期发现烟株中下部叶片出现水渍状暗绿色病斑，并迅速扩展成不规则大斑，湿度大时病部产生白色霉状物，最可能的病害是","options":["烟草黑胫病","烟草赤星病","烟草普通花叶病","烟草野火病"],"answer":[0],"explanation":"知识点为黑胫病症状识别。黑胫病典型症状为叶片水渍状暗绿大斑、湿度大时生白色霉层，并常伴随茎基部变黑。赤星病病斑为褐色圆形具同心轮纹；普通花叶病为花叶、畸形无霉层；野火病病斑周围有黄晕、无白色霉层。","tier":"挑战"},{"id":55,"type":"single","stem":"防治烟草蚜虫时，为减少病毒病传播，最合理的施药策略是","options":["在蚜虫迁飞高峰前及早防治并交替用药","等蚜虫大量发生后再集中喷药","只用一种内吸性药剂连续喷施","在烟叶采收前一周喷施高毒药剂"],"answer":[0],"explanation":"知识点为蚜虫防治与病毒病防控。蚜虫是病毒病主要传播媒介，应在迁飞高峰前早防。等大量发生后再防已造成传毒；单一药剂连用易产生抗性；采收前一周用高毒药剂影响烟叶安全性。","tier":"进阶"},{"id":56,"type":"single","stem":"烟草打顶后，为控制腋芽生长通常采用的方法是","options":["人工抹杈或使用抑芽剂","追施速效氮肥促进生长","增加灌溉量抑制腋芽","喷施赤霉素促进腋芽伸长"],"answer":[0],"explanation":"知识点为打顶后腋芽控制。打顶后腋芽萌发力强，需人工抹杈或施用抑芽剂。追施氮肥、增加灌溉、喷施赤霉素均会促进腋芽或烟株旺长，与控芽目标相反。","tier":"进阶"},{"id":57,"type":"single","stem":"烟叶成熟采收时，判断下部叶适宜采收的主要外观特征是","options":["叶面由绿转黄绿，主脉变白，叶尖下垂","叶片浓绿肥厚，叶面有光泽","叶面出现成熟斑，叶缘焦枯","叶片完全枯黄，主脉干缩"],"answer":[0],"explanation":"知识点为下部叶成熟采收标准。下部叶成熟时叶色转黄绿、主脉变白、叶尖下垂。浓绿肥厚为未熟；成熟斑和叶缘焦枯多为上部叶过熟表现；完全枯黄干缩则已过熟。","tier":"进阶"},{"id":58,"type":"single","stem":"烟草漂浮育苗中，出苗后基质表面出现绿色藻类，最直接有效的处理措施是","options":["适当通风降低棚内湿度并控制营养液浓度","增加喷水次数保持表面湿润","提高棚温促进藻类与烟苗竞争","向营养池中加入更多氮肥"],"answer":[0],"explanation":"知识点为苗床藻类防控。藻类在高温高湿、营养丰富的环境易滋生，应通风降湿并控制营养液浓度。增加喷水、提高温度、加氮肥都会加重藻类繁殖。","tier":"进阶"},{"id":59,"type":"single","stem":"某烟区移栽后遭遇持续低温阴雨，烟苗出现发黄、生长停滞，田间管理上应优先采取的措施是","options":["中耕松土提高地温并追施适量速效肥","大量灌水保持土壤湿润","喷施高浓度抑制剂控制旺长","立即揭膜让烟苗接受强光"],"answer":[0],"explanation":"知识点为低温阴雨后的田间补救。低温阴雨导致根系活力下降、吸收不良，应中耕提温、适量追肥促恢复。大量灌水降低地温；喷抑制剂与促恢复目标相反；突然揭膜强光易造成萎蔫。","tier":"进阶"},{"id":60,"type":"single","stem":"烟草黑胫病药剂防治中，移栽后至团棵期施药的重点部位是","options":["茎基部和根部","顶部嫩叶","叶面正面","花蕾和花序"],"answer":[0],"explanation":"知识点为黑胫病施药部位。黑胫病主要从茎基部和根部侵染，药剂应重点喷淋茎基部和根际。顶部嫩叶、叶面正面、花蕾花序均非主要侵染部位和施药重点。","tier":"基础"},{"id":6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赤星病","烟草青枯病"],"answer":[0],"explanation":"知识点为病毒病田间诊断。黄瓜花叶病由蚜虫传播，典型症状为叶片卷曲、主脉扭曲、植株矮化。黑胫病为茎基部黑褐色坏死；赤星病为叶片褐色圆形病斑；青枯病为植株萎蔫、茎部维管束变褐。","tier":"挑战"},{"id":81,"type":"multi","stem":"烟草漂浮育苗过程中，以下哪些操作有助于培育壮苗","options":["定期检查并调节苗池营养液浓度","根据苗龄和天气适时通风炼苗","苗盘长期保持深水层以稳定温度","发现病苗及时拔除并带出苗床","播种后始终遮阳避免强光直射"],"answer":[0,1,3],"explanation":"知识点为漂浮育苗壮苗管理。调节营养液浓度保证养分供应，适时通风炼苗提高抗逆性，及时拔除病苗防止蔓延，均为壮苗措施。长期深水层会导致根系缺氧、茎叶徒长；始终遮阳会造成光照不足、幼苗细弱。","tier":"挑战"},{"id":82,"type":"single","stem":"烤烟漂浮育苗中，播种后覆盖池膜的主要作用是保持池内温湿度和防止雨水冲淋，当幼苗出土达到什么程度时应及时揭去池膜？","options":["子叶平展后即可全部揭除","第一片真叶展开时揭除","出苗率达到八成左右时揭除","烟苗长到十字期后揭除"],"answer":[2],"explanation":"知识点为漂浮育苗揭膜时机。出苗率达到八成左右时揭膜可防止高温烫苗和徒长；子叶平展时苗还弱，过早揭膜易失水；第一片真叶展开时已偏晚，膜内高温易灼伤；十字期更晚，已造成高脚苗。","tier":"基础"},{"id":83,"type":"single","stem":"烟草移栽时，穴施肥料应与烟苗根系保持适当距离，主要原因是防止哪种现象发生？","options":["肥料挥发造成氮素损失","根系被高浓度肥料灼伤","肥料被土壤胶体固定","烟苗吸收养分过快徒长"],"answer":[1],"explanation":"知识点为移栽施肥安全距离。肥料集中穴施时浓度高，直接接触根系会造成烧根；挥发损失主要与表施和温度有关；土壤固定是磷钾的常见现象，与距离无直接关系；徒长由氮肥过量或水分过多引起，不是距离过近的主要后果。","tier":"挑战"},{"id":84,"type":"single","stem":"烟田起垄时要求垄体饱满、垄面平整，垄高一般根据当地气候和土壤条件确定，在雨水较多、地下水位较高的烟区，垄高应如何掌握？","options":["适当降低以便于培土","适当加高以利排水防涝","保持与干旱烟区相同高度","按烟株最终高度的一半确定"],"answer":[1],"explanation":"知识点为起垄高度与排水的关系。多雨高地下水位烟区需加高垄体，防止渍水伤根；降低垄高会加重涝害；不同气候区不能照搬同一高度；垄高与烟株最终高度无固定比例关系。","tier":"进阶"},{"id":85,"type":"single","stem":"烤烟田间管理中，打顶后烟株腋芽容易萌发，为抑制腋芽生长，生产上常采用人工抹杈或使用抑芽剂，下列哪种做法符合科学抑芽要求？","options":["打顶后立即抹杈并涂抹抑芽剂","打顶后等腋芽长到十厘米再抹除","只抹除上部腋芽保留下部腋芽","抑芽剂直接喷在烟株顶端切口"],"answer":[0],"explanation":"知识点为打顶后抑芽操作。打顶后立即抹杈并施药可减少养分消耗；腋芽长到十厘米已消耗大量养分；保留下部腋芽会继续消耗养分；抑芽剂应施于腋芽或全株，直接喷切口易造成药害且效果不佳。","tier":"进阶"},{"id":86,"type":"single","stem":"烟草黑胫病在田间常表现为茎基部出现黑褐色病斑并向上扩展，该病害的发生与下列哪种条件关系最密切？","options":["土壤干旱且气温偏低","田间积水且气温较高","空气干燥且光照强烈","土壤偏砂且有机质少"],"answer":[1],"explanation":"知识点为黑胫病发病条件。高温高湿、田间积水时病菌易侵染茎基部；干旱低温不利于发病；干燥强光抑制病害；砂土有机质少与黑胫病无直接对应关系。","tier":"挑战"},{"id":87,"type":"single","stem":"烟草育苗中，采用湿润育苗方式时，苗床水分管理应掌握的原则是下列哪一项？","options":["始终保持床面有明水","见干见湿、控水蹲苗","出苗前控水、出苗后大水","全期保持土壤饱和状态"],"answer":[1],"explanation":"知识点为湿润育苗水分管理。见干见湿有利于根系下扎和蹲苗；保持明水易烂根；出苗前应保湿、出苗后适当控水；全期饱和会导致根系缺氧。","tier":"进阶"},{"id":88,"type":"single","stem":"烟叶成熟采收时，判断下部叶成熟的主要外观特征是叶色由绿转为黄绿，叶面茸毛脱落，此外还应结合什么特征综合判断？","options":["叶尖开始枯焦","叶脉变白且主脉发亮","叶片变厚且脆","叶柄变短且弯曲"],"answer":[1],"explanation":"知识点为下部叶成熟特征。下部叶成熟时叶脉变白、主脉发亮，叶色黄绿；叶尖枯焦是病害或早衰；叶片变厚脆多为上部叶特征；叶柄变短弯曲不是成熟判断标准。","tier":"进阶"},{"id":89,"type":"single","stem":"某烟区移栽后遇到持续低温阴雨，烟苗出现发僵、生长缓慢的现象，此时最合理的田间管理措施是下列哪一项？","options":["立即大量追施速效氮肥","中耕松土提高地温并排水","喷施高浓度叶面肥促长","覆盖地膜后不再揭膜"],"answer":[1],"explanation":"知识点为低温阴雨后的田间管理。中耕松土可提高地温、排除积水，促进根系恢复；大量追氮会加重根系负担；高浓度叶面肥易烧苗；覆盖地膜后长期不揭会阻碍通风和根系生长。","tier":"挑战"},{"id":90,"type":"single","stem":"烟草花叶病在田间可通过汁液摩擦传播，农事操作时下列哪种做法能有效减少该病的传播？","options":["操作前用肥皂水洗手和工具","操作时先处理病株再处理健株","在露水未干时进行打顶抹杈","同一把剪刀连续使用不消毒"],"answer":[0],"explanation":"知识点为花叶病汁液传播的预防。肥皂水可钝化病毒，操作前洗手和工具能减少传播；先处理病株会将病毒带到健株；露水未干时操作易造成伤口传播；剪刀不消毒会连续传毒。","tier":"进阶"},{"id":91,"type":"single","stem":"漂浮育苗播种后，为使基质表面保持湿润而不积水，出苗期苗盘表面喷水应达到的状态是","options":["盘面见明水流动","基质表层发白再浇","轻压基质有水渗出","基质手握成团不滴水"],"answer":[2],"explanation":"知识点：漂浮育苗出苗期水分管理以基质吸足水又不积水为标准。轻压基质有水渗出说明基质已达饱和且未过量，符合要求；盘面见明水流动说明喷水过量易缺氧烂种；基质表层发白再浇说明已经偏干，出苗期不能等发白；手握成团不滴水是基质装盘时的手感标准，不是苗盘喷水的判断标准。","tier":"进阶"},{"id":92,"type":"single","stem":"烟草移栽时，同一地块中烟苗茎秆高度差异较大，为提高成活率，栽植深度应","options":["统一埋到第一片真叶","按苗高分别埋茎三分之一","统一埋到茎基部两厘米","按苗高分别埋到子叶痕"],"answer":[3],"explanation":"知识点：移栽深度应依苗高调整，以埋到子叶痕为适宜深度。按苗高分别埋到子叶痕可保证生长点外露且根系入土深度足够，成活率高；统一埋到第一片真叶会埋没心叶造成烂心；按苗高埋茎三分之一在高脚苗上仍偏浅、在矮苗上又过深；统一埋到茎基部两厘米对高苗太浅、对矮苗可能埋心。","tier":"进阶"},{"id":93,"type":"single","stem":"烟田追肥时，若在雨后土壤过湿条件下沿垄面撒施速效氮肥，最可能出现的问题是","options":["肥料随水流失且根系上浮","肥料被土壤胶体固定失效","肥料挥发导致叶片灼伤","肥料下渗造成深层固定"],"answer":[0],"explanation":"知识点：土壤过湿时表施速效氮肥易随径流和重力水淋失，并诱导根系向表层集中。雨后土湿撒施会使养分流失、根系上浮，降低肥效和抗旱力；被土壤胶体固定主要发生在磷肥与酸性土，与速效氮表施关系不大；挥发导致叶片灼伤是氨挥发熏叶，不是雨后撒施的主要问题；下渗造成深层固定不是氮肥在湿土表施的典型后果。","tier":"进阶"},{"id":94,"type":"single","stem":"烤烟大田生长中后期，下部叶片开始正常成熟采收，判断下部叶适熟的主要外观特征是","options":["叶面出现明显成熟斑","叶色由绿转黄绿且主脉发白","叶尖叶缘焦枯卷曲","叶面腺毛分泌大量黏液"],"answer":[1],"explanation":"知识点：下部叶适熟以叶色转黄绿、主脉变白发亮、叶面茸毛脱落为主要标志。叶色由绿转黄绿且主脉发白符合下部叶成熟特征；出现明显成熟斑多为上部叶或过熟表现；叶尖叶缘焦枯卷曲是病害或日灼症状；腺毛分泌大量黏液是烟蚜危害或叶面分泌物多的表现，不是成熟标志。","tier":"进阶"},{"id":95,"type":"single","stem":"烟草苗床期发现幼苗茎基部缢缩变细、子叶尚绿而幼苗倒伏，拔起病苗可见茎基腐烂，该病最可能是","options":["烟草炭疽病","烟草猝倒病","烟草黑胫病","烟草花叶病"],"answer":[1],"explanation":"知识点：猝倒病典型症状为苗期茎基部水浸状缢缩、幼苗倒伏而子叶暂绿。茎基缢缩倒伏、病苗茎基腐烂符合猝倒病；炭疽病以叶片产生褐色凹陷病斑为主，不首先表现茎基缢缩倒伏；黑胫病多发生在成株期，茎基部变黑并向上扩展，苗期少见典型倒伏；花叶病表现叶片花叶畸形，不引起茎基腐烂倒伏。","tier":"挑战"},{"id":96,"type":"single","stem":"烟田采用地膜覆盖栽培时，若在烟株团棵期发现膜下杂草顶起地膜，较合理的处置方式是","options":["揭开地膜彻底除草后不再覆膜","从膜孔处压土并随手拔除顶膜杂草","全田喷施灭生性除草剂后盖严","立即破膜放风并停止追肥"],"answer":[1],"explanation":"知识点：地膜覆盖田杂草顶膜时应局部压土并人工拔除，保持膜面完整。从膜孔处压土并拔除顶膜杂草可保住地膜增温保墒效果；揭膜后不再覆膜会丧失覆膜效应；全田喷灭生性除草剂易伤烟株；破膜放风并停止追肥与除草无关，还会影响烟株生长。","tier":"挑战"},{"id":97,"type":"single","stem":"烟草黑胫病在田间扩展较快时，下列农业防治措施中针对性最强的是","options":["增施磷钾肥提高抗性","及时清除病株并撒石灰消毒病穴","深翻晒垡降低土壤湿度","叶面喷施微量元素增强长势"],"answer":[1],"explanation":"知识点：黑胫病为土传病害，清除病株并对病穴消毒可减少菌源扩散。及时清除病株并撒石灰消毒病穴直接针对土壤传染源；增施磷钾肥是提高抗性的一般措施，针对性弱；深翻晒垡对已发病田块难以立即控制扩展；叶面喷微肥只起营养作用，不能阻断病害传播。","tier":"进阶"},{"i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用农药；物理防治指灯光诱杀等；农业防治指轮作、深耕等栽培措施。"},{"id":119,"type":"single","stem":"烟叶采收成熟度的判断中，下部叶适熟采收的外观特征是","options":["叶色浓绿，叶面光滑","叶色由绿转黄绿，叶尖微下垂","叶面出现成熟斑，主脉变白","叶片完全枯黄，叶柄自然脱落"],"answer":[1],"explanation":"知识点：烟叶成熟采收标准。下部叶适熟时叶色由绿转黄绿，叶尖微下垂。叶色浓绿说明未熟；出现成熟斑、主脉变白是中部叶或上部叶的成熟特征；叶片完全枯黄已过熟。"},{"id":120,"type":"single","stem":"某烟农在烤烟团棵期发现田间部分烟株心叶卷曲、皱缩，叶片变窄呈鼠尾状，拔起检查根系正常，最可能的病因是","options":["烟草普通花叶病","烟草黄瓜花叶病","烟草黑胫病","烟草根结线虫病"],"answer":[1],"explanation":"知识点：病毒病症状鉴别。黄瓜花叶病典型症状为心叶卷曲皱缩、叶片变窄呈鼠尾状。普通花叶病表现为花叶、疱斑；黑胫病茎基部变黑缢缩；根结线虫病根部有根结。"},{"id":121,"type":"single","stem":"某烟区在移栽后30天发现烟株生长缓慢，叶片自下而上黄化，拔起病株见根部有大小不等的瘤状突起，该烟田下一步最恰当的处理措施是","options":["立即追施大量氮肥促进生长","拔除病株并撒施石灰消毒病穴","全田喷施叶面肥缓解黄化","增加灌溉量冲刷根部瘤状物"],"answer":[1],"explanation":"知识点：根结线虫病田间处置。根结线虫病株应拔除并消毒病穴，防止扩散。追施氮肥不能解决线虫危害；喷施叶面肥只缓解表面症状；增加灌溉不能冲刷掉根结。"},{"id":122,"type":"multi","stem":"烟草育苗过程中，预防苗床病害发生应采取的措施包括","options":["选用无病种子并进行种子消毒","苗床使用未消毒的旧床土","控制苗床湿度避免积水","及时拔除病苗并带出苗床","苗床期保持高温高湿促苗快长"],"answer":[0,2,3],"explanation":"知识点：苗床病害综合预防。种子消毒、控湿防积水、拔除病苗都是有效预防措施。使用未消毒旧床土会带入病原；高温高湿环境利于病害发生而非预防。"},{"id":123,"type":"single","stem":"漂浮育苗池水pH值宜调控在哪个范围","options":["4.5～5.5","5.8～6.5","6.8～7.5","7.8～8.5"],"answer":[1],"explanation":"知识点为漂浮育苗池水酸碱度管理。烟苗适宜微酸性环境，pH 5.8～6.5利于养分吸收并抑制部分病原菌；4.5～5.5过酸易伤根；6.8～7.5近中性偏高，易诱发缺铁黄化；7.8～8.5偏碱，烟苗根系发育受阻。"},{"id":124,"type":"single","stem":"烟草催芽播种后苗床温度管理通常采用的变温策略是","options":["播种后高温促出苗，出苗后适当降温","播种后低温保湿，出苗后逐步升温","播种至出苗保持恒温，出苗后继续恒温","播种后先降温炼苗，出苗后再升温促长"],"answer":[0],"explanation":"知识点为育苗温度分段管理。播种后需较高温度促进萌发和出苗，出苗后降温可防徒长、培育壮苗；低温保湿会延迟出苗；全程恒温易造成高脚苗；先降温再升温与出苗生理需求相反。"},{"id":125,"type":"single","stem":"烤烟移栽时采用“井窖式”移栽的主要优势是","options":["深栽保温保湿，促进还苗成活","浅栽露坨，便于根系呼吸","斜栽靠垄，减少日灼伤苗","平栽覆土，抑制杂草萌发"],"answer":[0],"explanation":"知识点为井窖式移栽技术要点。井窖式移栽把苗栽入较深井窖，能保温保湿、缩短还苗期；浅栽露坨易失水伤苗；斜栽靠垄不是该技术特点；平栽覆土与井窖式做法不符。"},{"id":126,"type":"single","stem":"烟田发现烟株中下部叶片出现“缺钾”症状，最典型的表现是","options":["叶尖和叶缘先发黄，逐渐向叶内扩展","叶脉间失绿，叶脉仍保持绿色","新叶小而簇生，顶芽萎缩","叶片出现水渍状暗绿斑，随后腐烂"],"answer":[0],"explanation":"知识点为烟草缺钾症状识别。缺钾先从老叶叶尖叶缘发黄焦枯，再向叶内发展；叶脉间失绿多为缺镁；新叶簇生顶芽萎缩常见缺硼或缺钙；水渍状暗绿斑腐烂属病害或涝害表现。"},{"id":127,"type":"single","stem":"烟草苗床期防治猝倒病，在发病初期较合理的处置是","options":["立即拔除病苗并喷施对症药剂控制蔓延","大量灌水稀释病原后任其自然恢复","提高苗床湿度并加盖遮阳网闷棚","仅撒施草木灰覆盖病斑不再用药"],"answer":[0],"explanation":"知识点为苗床猝倒病应急处置。发病初期应清除病苗并用药控制中心病株；大量灌水会加速病原传播；提高湿度闷棚更利于病害流行；只撒草木灰不能有效控制病情扩展。"},{"id":128,"type":"single","stem":"烟叶移栽后还苗期遇连续阴雨，田间管理应优先采取的措施是","options":["及时清沟排水，防止渍害沤根","加大追肥量促进快速生长","深中耕培土提高地温","喷施抑制蒸腾剂减少水分吸收"],"answer":[0],"explanation":"知识点为还苗期水分管理。连续阴雨易积水沤根，应优先排水降湿；加大追肥在根系未恢复时易烧根；深中耕在湿土条件下易破坏结构；抑制蒸腾剂并非还苗期常规优先措施。"},{"id":129,"type":"single","stem":"烟草打顶后抹杈不及时，最可能造成的后果是","options":["腋芽消耗养分，影响上部叶开片和品质","主茎继续伸长，增加有效叶数","根系活力增强，提高钾素吸收","叶片成熟期提前，利于集中采收"],"answer":[0],"explanation":"知识点为打顶抹杈的养分调控作用。打顶后腋芽若不及时抹除会消耗大量养分，导致上部叶变小、品质下降；主茎不会因此继续增加有效叶；根系活力和钾吸收不会因此增强；成熟期也不会提前。"},{"id":130,"type":"single","stem":"烟田蚜虫防治中，利用银灰色地膜驱避蚜虫的机理主要是","options":["反射短波光，干扰蚜虫定位寄主","释放性信息素，诱杀雄蚜","提高地表温度，灼伤蚜虫足部","遮挡雨水，减少蚜虫迁飞降落"],"answer":[0],"explanation":"知识点为物理防治蚜虫原理。银灰色膜反射短波光，干扰蚜虫寻找寄主；性信息素诱杀属生物防治手段；提高地温灼伤足部不成立；遮挡雨水与驱避蚜虫无直接关系。"},{"id":131,"type":"single","stem":"烟叶成熟采收时，判断下部叶适熟的主要外观特征是","options":["叶色由绿转黄绿，主脉发白，叶尖下垂","叶色浓绿，叶面茸毛密布，主脉青绿","叶面出现焦斑，叶缘干枯卷曲","叶片变厚发脆，背面呈灰白色"],"answer":[0],"explanation":"知识点为烟叶成熟度判断。下部叶适熟时叶色转黄绿、主脉发白、叶尖下垂；浓绿茸毛密布为未熟；焦斑干枯为过熟或病害；变厚发脆灰白多为病态或异常叶。"},{"id":132,"type":"single","stem":"某烟农在移栽前将烟苗放在阳光下直接暴晒两天再移栽，结果还苗缓慢，主要原因是","options":["烟苗失水严重，根系活力下降","烟苗光照过强，叶绿素合成过多","烟苗茎秆变硬，移栽后不易折断","烟苗适应了强光，移栽后不需遮阴"],"answer":[0],"explanation":"知识点为移栽前炼苗方法。暴晒造成烟苗严重失水，根系活力下降，还苗慢；叶绿素合成增多不是还苗慢主因；茎秆变硬并非主要问题；适应强光不等于不需缓苗。"},{"id":133,"type":"single","stem":"烟田发现部分烟株叶片呈花叶、皱缩，且田间蚜虫量较大，下一步最合理的处置是","options":["及时防治蚜虫并拔除病株，减少毒源传播","只追施氮肥促进病株恢复生长","全田灌水淹没垄面抑制病毒扩散","摘除所有病叶后不再防治蚜虫"],"answer":[0],"explanation":"知识点为烟草病毒病综合防控。蚜虫是传播媒介，应治蚜并清除病株减少毒源；单追氮肥不能治病毒病；灌水淹垄易伤根且不能抑制病毒；只摘病叶不治蚜仍会继续传播。"},{"id":134,"type":"single","stem":"漂浮育苗播种后，营养池水面应保持的高度是使育苗盘底部浸入水中约多少厘米","options":["1～2厘米","3～4厘米","5～6厘米","7～8厘米"],"answer":[0],"explanation":"知识点为漂浮育苗水分管理。正确项1～2厘米可保证基质通过毛细作用吸足水分而不过湿。3～4厘米浸水过深易造成基质过湿、根系缺氧；5～6厘米使盘体漂浮不稳、出苗不齐；7～8厘米已接近淹没盘面，生产上不会采用。"},{"id":135,"type":"single","stem":"烟草育苗期出现幼苗茎基部缢缩、倒伏，湿度大时病部可见白色棉絮状霉层，应首先判断为","options":["猝倒病","立枯病","炭疽病","黑胫病"],"answer":[0],"explanation":"知识点为苗期病害识别。猝倒病典型症状为茎基缢缩倒伏并生白色棉絮状霉层。立枯病病部呈褐色、霉层不明显；炭疽病产生圆形凹陷病斑；黑胫病主要发生于大田成株茎基，苗期极少表现该症状。"},{"id":136,"type":"single","stem":"烤烟移栽时，井窖式移栽相比常规膜上移栽最突出的优势是","options":["深栽保温且还苗快","省去覆膜环节","不需浇定根水","可完全替代追肥"],"answer":[0],"explanation":"知识点为移栽方式比较。井窖式移栽使烟苗处于较深、温度稳定的土体环境中，利于深栽和提早还苗。省去覆膜并非其本质优势；定根水仍需浇；追肥任何移栽方式都不能省略。"},{"id":137,"type":"single","stem":"烟田追肥时，若在烟株团棵期一次性重施氮肥，最可能导致的结果是","options":["烟叶贪青晚熟、上部叶身份变薄","烟株还苗加快、成熟提早","烟叶钾含量明显提高","根系下扎深度显著增加"],"answer":[0],"explanation":"知识点为氮肥运筹。团棵期一次性重施氮肥会造成氮素供应后移，引起贪青晚熟并影响上部叶充实度。还苗提早主要靠移栽质量；钾含量取决于钾肥供应；根系下扎受土壤水分和耕层影响，与该施肥方式无直接因果。"},{"id":138,"type":"single","stem":"烟田发现烟蚜数量上升，为保护烟蚜茧蜂等天敌，优先采用的防治措施是","options":["释放瓢虫并喷施选择性杀虫剂","立即喷施广谱有机磷农药","加大菊酯类药剂浓度","全田撒施呋喃丹颗粒剂"],"answer":[0],"explanation":"知识点为蚜虫综合防治。释放瓢虫配合选择性药剂可兼顾控蚜与护益。广谱有机磷、菊酯类高浓度使用及撒施呋喃丹均会大量杀伤天敌，与保护天敌目标相反。"},{"id":139,"type":"single","stem":"烟叶成熟采收判断中，下部叶适宜的采收外观特征是","options":["叶色由绿转黄绿、主脉变白、叶面出现成熟斑","叶色浓绿、叶面光滑、主脉青绿","叶色深绿、叶尖焦枯、叶缘上卷","叶色黄白、叶片干脆、主脉褐变"],"answer":[0],"explanation":"知识点为成熟采收标准。下部叶成熟时叶色转黄绿、主脉变白并出现成熟斑。浓绿光滑表示未熟；深绿焦尖多为病害或灼伤；黄白干脆已过熟。"},{"id":140,"type":"single","stem":"烟草黑胫病在田间流行的关键条件是","options":["高温高湿且土壤排水不良","低温干燥且光照充足","土壤偏砂且有机质低","昼夜温差大且风力强"],"answer":[0],"explanation":"知识点为黑胫病流行条件。高温高湿配合排水不良最利于病菌侵染和传播。低温干燥、砂质低有机质土壤及温差大风力强均不利于该病流行。"},{"id":141,"type":"single","stem":"某烟区移栽后遇持续低温阴雨，烟苗出现叶片发紫、生长停滞，最可能的原因是","options":["低温抑制磷素吸收","土壤钾素过量","光照过强导致灼伤","氮肥施用不足"],"answer":[0],"explanation":"知识点为低温对养分吸收的影响。低温阴雨抑制根系对磷的吸收，导致花青素积累使叶片发紫。钾过量不会致紫；光照过强与阴雨矛盾；缺氮表现为整株黄化而非发紫。"},{"id":142,"type":"single","stem":"烟田采用地膜覆盖栽培时，膜孔封堵不严最可能引起的后果是","options":["膜下高温蒸汽灼伤烟苗","土壤水分蒸发加快","地温明显降低","杂草完全无法生长"],"answer":[0],"explanation":"知识点为地膜覆盖管理。膜孔未封严时膜下热空气从孔口逸出，易灼伤烟苗茎叶。封堵不严反而利于水分散失和杂草从孔口生长；地温不会因此明显降低。"},{"id":143,"type":"single","stem":"烟农在旺长期发现烟株中下部叶片出现水渍状暗绿色病斑，迅速扩展并沿叶脉蔓延，田间湿度大，应优先采取的处置是","options":["拔除病株并喷施防治黑胫病药剂","大量追施氮肥增强长势","继续观察待症状稳定后处理","仅摘除病叶不作药剂防治"],"answer":[0],"explanation":"知识点为黑胫病田间应急处置。水渍状暗绿病斑沿叶脉扩展是黑胫病典型表现，应及时拔除病株并施药控制蔓延。追氮会加重病情；拖延观察会扩大侵染；仅摘叶难以阻断土壤和雨水传播。"},{"id":144,"type":"multi","stem":"烟草漂浮育苗中，为预防苗期病害发生，可采取的措施包括","options":["播种前对育苗盘和基质进行消毒","控制营养池水位避免基质过湿","保持苗棚通风降低棚内湿度","发现病苗后继续留床观察","阴雨天全天密闭棚膜保温"],"answer":[0,1,2],"explanation":"知识点为苗期病害综合预防。消毒育苗盘和基质、控制水位、通风降湿均为有效预防措施。病苗继续留床会成为传染源；阴雨天全天密闭会升高棚内湿度，利于病害发生。"},{"id":145,"type":"single","stem":"漂浮育苗播种后，营养池水面应保持与育苗盘底面接触而盘面不浸水，其主要目的是","options":["保证种子吸水萌发同时避免盘面长期积水缺氧","提高池水温度以加快出苗速度","防止藻类在盘面生长遮挡光照","减少营养液蒸发以降低补水量"],"answer":[0],"explanation":"知识点为漂浮育苗水分管理。种子萌发需要吸胀吸水，盘底面接触水面可通过基质毛细作用供水，而盘面不浸水可保证基质通气、避免缺氧烂种。提高水温主要靠温控设施而非水位；防藻靠遮光和药剂，水位高低不是关键；减少蒸发靠覆盖或池体结构，不是把水位控制在盘底刚接触的主因。"},{"id":146,"type":"single","stem":"烟草苗床期出现幼苗茎基部缢缩、倒伏，湿度大时病部可见白色棉絮状霉层，最可能是","options":["猝倒病","立枯病","炭疽病","黑胫病"],"answer":[0],"explanation":"知识点为苗期病害识别。猝倒病典型症状是茎基缢缩、幼苗倒伏，高湿时产生白色棉絮状霉层。立枯病病部缢缩但霉层不典型、病苗常直立枯死；炭疽病在叶片形成凹陷病斑而非茎基缢缩倒伏；黑胫病主要在成株茎基部变黑，苗期少见典型棉絮状霉层。"},{"id":147,"type":"single","stem":"烤烟移栽时采用“膜下小苗移栽”，栽后立即封严膜口的主要作用是","options":["保温保湿并防止膜内热气从孔口灼伤烟苗","减少膜内光照以抑制杂草","提高膜内二氧化碳浓度促进光合","防止雨水进入垄体造成肥料流失"],"answer":[0],"explanation":"知识点为膜下小苗移栽操作。封严膜口可维持膜内温湿度、促进还苗，同时避免膜内高温气体从孔口集中逸出灼伤幼苗。遮光抑草靠膜本身颜色或除草剂；膜内二氧化碳变化不是封口主因；防雨水流失靠垄体沟渠和覆膜完整性，封口作用在于保温防灼伤。"},{"id":148,"type":"single","stem":"烟株团棵期追施氮肥后遇连续降雨，田间出现烟株徒长、叶色浓绿、下部叶不易落黄，最合理的补救措施是","options":["控制灌水并叶面喷施磷钾肥促进代谢平衡","立即再追一次氮肥补偿淋失的养分","深中耕切断部分根系抑制养分吸收","喷施赤霉素促进叶片快速伸展"],"answer":[0],"explanation":"知识点为田间养分调控。降雨后氮肥淋失少反而易造成氮素过多、烟株徒长，应控水并补充磷钾以平衡营养、促进成熟落黄。再追氮肥会加重徒长；深中耕断根伤苗且不能解决氮素过剩；赤霉素促进细胞伸长会使叶片更贪青，方向相反。"},{"id":149,"type":"single","stem":"烟草打顶后要及时抹杈，但抹杈过早易造成伤口过多，正确的做法是","options":["腋芽长到3~5厘米时选晴天上午抹除并带出田外","腋芽刚露头米粒大小时立即抹除","腋芽长到10厘米以上时连同部分主茎叶一起抹除","任腋芽长到开花后再一次性抹除"],"answer":[0],"explanation":"知识点为打顶抹杈技术。腋芽长到3~5厘米时抹除，伤口适中、操作方便，晴天上午利于伤口愈合，带出田外可减少病虫传播。芽刚露头抹除易反复、伤口密集；芽过大消耗养分且常需撕伤主茎；任其开花则严重消耗养分、降低上部叶质量。"},{"id":150,"type":"single","stem":"烟田发现烟蚜数量上升，计划释放瓢虫进行生物防治，释放前应重点考虑","options":["田间近期是否使用过广谱杀虫剂","当天是否安排了打顶抹杈","烟株是否已进入成熟采烤期","垄体是否已经完成中耕培土"],"answer":[0],"explanation":"知识点为生物防治配套条件。释放天敌前必须确认近期未施用广谱杀虫剂，否则瓢虫会被杀伤而失效。打顶抹杈是农事操作，不影响瓢虫定殖但非释放前首要条件；成熟采烤期与释放时机有关但非关键限制；中耕培土与天敌释放无直接冲突。"},{"id":151,"type":"single","stem":"烤烟生长后期烟青虫幼虫已钻入烟叶内部取食，此时防治效果最好的措施是","options":["在幼虫三龄前选用生物农药重点喷施心叶和嫩叶","在幼虫钻蛀后喷施触杀型药剂于叶面","在成虫期喷施胃毒剂于下部老叶","在幼虫钻蛀后撒施毒土于烟株根际"],"answer":[0],"explanation":"知识点为烟青虫防治时机。幼虫三龄前多在叶面取食，选用生物农药喷心叶和嫩叶可有效控制；钻蛀后触杀剂难以接触虫体；成虫期喷胃毒剂于老叶不对靶；根际毒土针对地下害虫而非钻蛀叶片的烟青虫。"},{"id":152,"type":"single","stem":"烟苗移栽前进行“断水炼苗”，其主要目的是","options":["提高烟苗抗逆性以缩短还苗期","降低烟苗含水量以便长途运输","促使烟苗根系老化便于拔苗","减少苗床病害发生概率"],"answer":[0],"explanation":"知识点为移栽前炼苗。断水炼苗使烟苗细胞液浓度提高、茎叶坚韧，栽后抗逆性强、还苗快。便于运输和拔苗只是附带效果而非主要目的；炼苗与苗床病害无直接因果关系。"},{"id":153,"type":"single","stem":"某烟区土壤pH为5.0，计划种植烤烟，最适宜的改良措施是","options":["施用适量石灰提高pH至适宜范围","大量施用硫酸铵酸化土壤","增施过磷酸钙降低土壤pH","灌水洗盐以降低土壤酸度"],"answer":[0],"explanation":"知识点为土壤酸碱度调控。烤烟适宜pH约5.5~6.5，pH5.0偏酸，施石灰可中和酸度。硫酸铵为生理酸性肥会进一步酸化；过磷酸钙含游离酸可能降低pH；灌水洗盐针对盐碱土，对酸性土无效。"},{"id":154,"type":"multi","stem":"烟草漂浮育苗中，为预防苗期猝倒病和立枯病，下列管理措施合理的有","options":["播种前对苗盘和基质进行消毒处理","苗床期保持盘面基质见干见湿、避免长期积水","发现病苗后立即拔除并带出苗床销毁","为促苗快长，出苗后每天早晚各浇一次透水","将苗床温度始终控制在35℃以上以抑制病菌"],"answer":[0,1,2],"explanation":"知识点为苗期病害综合预防。苗盘基质消毒可减少初侵染源；见干见湿避免高湿环境；拔除病苗并销毁可切断传播。每天浇透水会造成高湿缺氧，利于病害；35℃以上高温抑菌同时会灼伤烟苗、抑制生长，不是合理措施。"},{"id":155,"type":"single","stem":"烟草漂浮育苗中，播种后覆盖基质厚度通常以盖没种子后尚余多少为宜","options":["0.2～0.3厘米","0.5～1.0厘米","1.5～2.0厘米","2.5～3.0厘米"],"answer":[0],"explanation":"知识点为漂浮育苗播种后基质覆盖厚度。覆盖过厚会阻碍出苗，过薄易露籽干芽，通常盖没种子后再覆0.2～0.3厘米即可。0.5～1.0厘米偏厚，出苗迟缓；1.5～2.0厘米明显过厚，易闷芽；2.5～3.0厘米过厚，基本不能正常出苗。"},{"id":156,"type":"single","stem":"烟草移栽时，井窖式移栽与膜下小苗移栽相比，其主要优势在于","options":["烟苗栽后不需还苗直接进入旺长","可提早移栽并利用井窖保温保湿","完全免除后期追肥作业","适合所有土壤类型且不需整地"],"answer":[1],"explanation":"知识点为井窖式移栽的特点。井窖式移栽利用井窖的保温保湿作用，可适当提早移栽，促进早发。说栽后不需还苗直接旺长不准确，任何移栽都有还苗过程；说完全免除追肥不符合实际；说适合所有土壤且不需整地也不成立。"},{"id":157,"type":"single","stem":"烤烟田间管理中，打顶后留叶数的确定主要依据","options":["烟株高度和茎围","品种特性与烟叶着生部位","土壤颜色和坡度","移栽当天的天气"],"answer":[1],"explanation":"知识点为打顶留叶原则。留叶数主要根据品种特性、烟叶着生部位及烟株长势确定，以保证上部叶充分开展。烟株高度和茎围是长势参考但非主要依据；土壤颜色和坡度与留叶数无关；移栽当天天气不影响留叶数确定。"},{"id":158,"type":"single","stem":"烟草黑胫病在田间发病后，下列处置措施中正确的是","options":["及时拔除病株并带出田外销毁","保留病株以观察病情发展","将病株就地翻压入土","把病株叶片采下晒干后混入好烟"],"answer":[0],"explanation":"知识点为黑胫病田间处置。黑胫病为土传病害，发现病株应及时拔除并带出田外销毁，减少菌源。保留病株会继续传播；就地翻压仍可污染土壤；病叶混入好烟会造成损失和传播风险。"},{"id":159,"type":"single","stem":"烟田发现烟蚜数量上升，采用释放瓢虫进行防治，这种方式属于","options":["化学防治","生物防治","物理防治","农业防治"],"answer":[1],"explanation":"知识点为病虫害防治方法分类。释放瓢虫等天敌防治害虫属于生物防治。化学防治指使用农药；物理防治指利用光、热、色板等物理手段；农业防治指通过耕作、轮作等农艺措施。"},{"id":160,"type":"single","stem":"烟草苗床期发现部分烟苗茎基部缢缩、倒伏，最可能的原因是","options":["猝倒病","花叶病","黑胫病","赤星病"],"answer":[0],"explanation":"知识点为苗期病害识别。猝倒病典型症状是茎基部缢缩、幼苗倒伏。花叶病表现为叶片花叶斑驳；黑胫病多在成株期茎基部变黑；赤星病主要为害叶片形成病斑。"},{"id":161,"type":"single","stem":"烟田采用地膜覆盖栽培时，揭膜时间通常应根据","options":["烟株长势和气温回升情况确定","地膜颜色深浅确定","烟农经验随意确定","移栽后固定第10天确定"],"answer":[0],"explanation":"知识点为地膜覆盖管理。揭膜时间应结合烟株长势和气温回升情况，避免高温灼苗或揭膜过晚影响根系。地膜颜色不是揭膜时间依据；随意确定不科学；固定天数不考虑天气和长势，易造成不利影响。"},{"id":162,"type":"single","stem":"烟农反映烟苗移栽后缓苗慢、叶片发紫，田间检查发现土壤板结且近期低温，下一步最合理的处置是","options":["立即大量追施速效氮肥","中耕松土并适当提高地温","马上喷施高浓度除草剂","停止一切田间作业等待回暖"],"answer":[1],"explanation":"知识点为移栽后缓苗不良的原因与处置。土壤板结、低温导致根系活力差、吸磷受阻而叶片发紫，应先中耕松土、提高地温促根。大量追氮在根系弱时易伤根；喷除草剂会加重药害；停止作业等待不利于改善土壤通气。"},{"id":163,"type":"multi","stem":"烟草大田期进行中耕培土的作用包括","options":["疏松土壤、改善通气","促进不定根发生","增强烟株抗倒伏能力","直接杀灭所有地下害虫","替代全部追肥作业"],"answer":[0,1,2],"explanation":"知识点为中耕培土的作用。中耕培土可疏松土壤、改善通气，促进不定根发生，增强抗倒伏能力。中耕培土不能直接杀灭所有地下害虫；也不能替代全部追肥作业。"},{"id":164,"type":"single","stem":"漂浮育苗池中营养液EC值突然从1.2 mS/cm升至2.5 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现蕾开花","增加烟苗单株叶片总数","使烟苗根系完全脱离基质"],"answer":[0],"explanation":"炼苗通过控水、通风、降温等手段增强烟苗适应大田的能力，提高成活率；炼苗不促进早花；不增加叶片总数；也不要求根系完全脱离基质。"},{"id":206,"type":"single","stem":"烤烟大田移栽后出现“还苗期”叶片发黄，最合理的判断是","options":["烟株根系受伤尚未恢复吸收","烟株已进入旺长期需追肥","烟田已发生黑胫病必须拔除","烟叶已成熟需要及时采收"],"answer":[0],"explanation":"还苗期烟苗根系受损，吸收能力弱，短暂发黄属正常现象；旺长期尚未到来；单凭发黄不能判定黑胫病；成熟采收更不符合苗期特征。"},{"id":207,"type":"single","stem":"烟田打顶后立即抹杈，容易造成的后果是","options":["腋芽再生加快且伤口易感染","烟株根部发育明显增强","烟叶成熟期明显推迟","烟碱含量显著下降"],"answer":[0],"explanation":"打顶后腋芽生长旺盛，过早抹杈易刺激再生并增加伤口感染风险，应待腋芽长到一定长度再抹；抹杈不会增强根系；不推迟成熟；也不会使烟碱显著下降。"},{"id":208,"type":"single","stem":"烟田发现烟蚜数量上升，为减少病毒病传播，优先采取的措施是","options":["及时喷施杀虫剂并清除田边杂草","大量灌水冲刷烟株叶片","增施氮肥促进烟株生长","推迟移栽时间避开蚜虫"],"answer":[0],"explanation":"蚜虫是病毒病主要传播媒介，及时治蚜并清除田边杂草可减少毒源和虫源；灌水冲刷效果有限且易传播；增施氮肥使烟株柔嫩反而诱蚜；推迟移栽不能解决田间蚜量问题。"},{"id":209,"type":"single","stem":"烟田施用氮肥过多而钾肥不足时，烟叶最可能出现的变化是","options":["叶色浓绿、叶片肥厚且易感病","叶色淡黄、叶片薄且易落黄","叶脉发白、叶片早衰且易烤青","叶面皱缩、叶尖干枯且易早花"],"answer":[0],"explanation":"氮多钾少使烟株贪青徒长，叶色浓绿肥厚，抗病性下降；叶色淡黄薄是缺氮；叶脉发白早衰多为缺钾或早衰；皱缩干枯早花不是氮钾比例失调的典型表现。"},{"id":210,"type":"single","stem":"某烟农在移栽后连续降雨、田间积水，烟株出现根部发黑、叶片萎蔫，最可能是","options":["黑胫病在积水条件下加重","花叶病随雨水快速传播","烟青虫在根部大量取食","赤星病从下部叶向上蔓延"],"answer":[0],"explanation":"黑胫病在高温高湿、田间积水时易发，表现根茎发黑、萎蔫；花叶病主要表现花叶皱缩；烟青虫取食叶片；赤星病主要危害叶片形成病斑。"},{"id":211,"type":"single","stem":"烟农在烟株现蕾期发现部分烟株长势过旺、叶色浓绿，计划打顶，正确的处置是","options":["待花序伸长后及时打顶并合理留叶","立即将所有烟株连根拔除","推迟到烟叶采收后再打顶","只打顶不抹杈以保留养分"],"answer":[0],"explanation":"现蕾后待花序伸长及时打顶，可调控养分分配并合理留叶；拔除烟株不现实；采收后打顶失去意义；只打顶不抹杈会使腋芽消耗养分。"},{"id":212,"type":"multi","stem":"关于烤烟漂浮育苗基质装盘与播种的操作，正确的做法有","options":["基质装盘前应调节含水量至手握成团","播种后覆盖基质厚度以薄盖不见种为宜","播后及时将苗盘放入营养池并保温保湿","基质装盘越紧实越有利于根系盘结","播种后应把苗盘放在阳光下暴晒催芽"],"answer":[0,1,2],"explanation":"基质含水量适宜、薄盖种子、播后入池保温保湿均利于出苗；装盘过紧会缺氧影响根系；暴晒会使基质失水且温度过高，影响出苗。"},{"id":213,"type":"single","stem":"烟草漂浮育苗播种后，苗盘放入育苗池，覆盖无纺布的主要作用是","options":["保温保湿并防止种子被水冲走","遮挡强光避免藻类繁殖","防止烟苗徒长形成高脚苗","隔离蚜虫传播病毒病"],"answer":[0],"explanation":"知识点为漂浮育苗播种后的覆盖管理。无纺布覆盖可保温保湿、稳定出苗环境并防止种子被水冲散，故正确；遮挡强光并非其主要目的，藻类控制靠遮阳网或水质管理，故B错；防徒长靠温湿度与剪叶管理，覆盖无纺布不解决高脚苗，故C错；隔离蚜虫需防虫网或药剂，无纺布不具隔离蚜虫传毒功能，故D错。"},{"id":214,"type":"single","stem":"烟草苗床期出现烟苗茎叶徒长、根系少而弱，最先应检查的管理环节是","options":["苗床温度与氮肥用量","苗床是否喷施了多菌灵","育苗盘是否用过消毒液","覆盖物是否使用无纺布"],"answer":[0],"explanation":"知识点为苗床期徒长苗的成因诊断。徒长苗多因温度偏高、氮肥偏多、湿度大、光照不足引起，故应首先检查温度与氮肥，A正确；多菌灵是杀菌剂，不直接导致徒长，B错；育苗盘消毒液残留可能伤根但通常表现为抑制而非徒长，C错；无纺布覆盖与徒长无直接因果，D错。"},{"id":215,"type":"single","stem":"烟草移栽时采用地膜覆盖栽培，膜口封土不严最可能造成的后果是","options":["膜内杂草顶膜烧苗","膜内温度过低抑制还苗","膜下水分过多引起烂根","膜口进风揭膜伤苗"],"answer":[0],"explanation":"知识点为地膜覆盖栽培的封口要求。膜口封土不严会使膜内杂草生长并顶起地膜，晴天高温易灼伤烟苗，故A正确；地膜本身增温，膜口不严不会导致温度过低，B错；膜下水分过多主要与排水和膜面坡度有关，封口不严反而易散湿，C错；揭膜伤苗多因大风或压膜不实，与膜口封土不严的直接后果不符，D错。"},{"id":216,"type":"single","stem":"烤烟大田期发现烟株中下部叶片出现水渍状暗绿色病斑，迅速扩展并沿叶脉蔓延，田间湿度大时病部产生白色霉状物，最可能是","options":["烟草黑胫病","烟草赤星病","烟草霜霉病","烟草普通花叶病"],"answer":[2],"explanation":"知识点为烟草常见病害症状识别。霜霉病在湿度大时病部产生白色霉状物，病斑扩展快，故C正确；黑胫病主要危害茎基部和根部，表现为黑胫和萎蔫，故A错；赤星病病斑为褐色圆形轮纹斑，后期无白色霉层，故B错；普通花叶病为花叶、泡斑等病毒症状，无霉状物，故D错。"},{"id":217,"type":"single","stem":"烟草育苗池水pH偏高最直接的影响是","options":["铁、锰等微量元素有效性下降","池水溶氧量迅速升高","烟苗对磷的吸收明显增强","基质保水能力显著提高"],"answer":[0],"explanation":"知识点为漂浮育苗水质管理。pH偏高会使铁、锰、锌等微量元素形成沉淀，有效性下降，故A正确；pH升高与溶氧量升高无直接因果，B错；pH偏高通常降低磷的有效性而非增强吸收，C错；基质保水能力由基质配比决定，与池水pH无关，D错。"},{"id":218,"type":"single","stem":"烟草大田期进行中耕培土，培土高度一般以不埋没心叶为原则，其主要作用是","options":["促进不定根发生并增强抗倒伏能力","降低土壤透气性抑制杂草","减少烟株对钾素的吸收","加速下部叶片落黄成熟"],"answer":[0],"explanation":"知识点为中耕培土的栽培作用。培土可促进茎基部不定根发生、增强抗倒伏和排水能力，故A正确；培土利于透气而非降低透气性，B错；培土不减少钾素吸收，C错；下部叶落黄与培土无直接关系，D错。"},{"id":219,"type":"single","stem":"烟草苗期猝倒病多在低温高湿、幼苗密集时发生，防治上首先应采取的措施是","options":["降低苗床湿度并及时间苗通风","提高苗床温度并增施氮肥","喷施叶面肥增强幼苗长势","增加覆盖物厚度保温保湿"],"answer":[0],"explanation":"知识点为猝倒病的发生条件与防治原则。低温高湿、幼苗密集利于猝倒病流行，应降湿、间苗、通风，故A正确；增施氮肥会加重病害，B错；叶面肥不能替代环境调控，C错；增加覆盖物会加重高湿，D错。"},{"id":220,"type":"single","stem":"烟叶采收成熟度判断中，下部叶适熟采收的典型外观特征是","options":["叶面呈黄绿色且主脉发白","叶面深绿且叶尖上翘","叶面出现焦边且主脉变褐","叶面浓绿且茸毛密集"],"answer":[0],"explanation":"知识点为烟叶成熟采收标准。下部叶适熟时叶色由绿转黄绿、主脉发白、叶面茸毛脱落，故A正确；深绿、叶尖上翘为未熟特征，B错；焦边、主脉变褐为过熟或病态，C错；浓绿、茸毛密集为未熟，D错。"},{"id":221,"type":"single","stem":"某烟农在移栽后遇持续阴雨，烟田出现积水，烟株叶片发黄、根系变褐，此时最合理的处置是","options":["及时疏通沟渠排水并浅中耕散墒","立即追施大量速效氮肥促苗","全田喷施杀菌剂后不再排水","覆盖地膜减少水分蒸发"],"answer":[0],"explanation":"知识点为涝害后烟田管理。积水导致根系缺氧变褐，应先排水、浅中耕散墒改善通气，故A正确；积水未排时追施大量氮肥会加重根系负担，B错；只喷药不排水不能解决缺氧，C错；覆盖地膜会阻碍散墒，D错。"},{"id":222,"type":"single","stem":"漂浮育苗播种后至出苗前，苗盘表面覆盖物的主要作用是保持基质湿润和","options":["提高苗盘温度","增加光照强度","促进根系下扎","降低池水盐分"],"answer":[0],"explanation":"知识点为漂浮育苗出苗期管理。播种后覆盖无纺布或薄膜可保温保湿，促进出苗整齐，故A正确；覆盖物会削弱光照而非增加，B错；根系下扎主要受基质和水分影响，非覆盖物直接作用，C错；覆盖物不改变池水盐分，D错。"},{"id":223,"type":"single","stem":"烟草育苗中，剪叶前一天应停止浇水的主要目的是","options":["让叶片变硬便于操作","降低基质含水量防止伤流","抑制病菌随水传播","促使烟苗提前进入成苗期"],"answer":[1],"explanation":"知识点为剪叶前水分管理。剪叶前控水可使基质偏干、叶片挺实，减少剪叶时伤流和感染，故B正确；叶片变硬是控水的表现而非目的，A错；控水不能替代消毒防病，C错；剪叶不改变成苗进程，D错。"},{"id":224,"type":"single","stem":"烤烟移栽时，若地温偏低且土壤墒情较好，最适宜的栽烟方式是","options":["深栽浅覆土","浅栽深覆土","深栽深覆土","浅栽浅覆土"],"answer":[0],"explanation":"知识点为移栽深度与覆土。地温低时深栽可保护根系、浅覆土利于升温，故A正确；浅栽深覆土使生长点埋土过深，B错；深栽深覆土升温慢，C错；浅栽浅覆土根系易受旱，D错。"},{"id":225,"type":"single","stem":"烟田追肥时，硝态氮肥与铵态氮肥相比，其肥效特点是","options":["肥效慢而持久","易被土壤胶体吸附","肥效快但易随水淋失","在淹水条件下更稳定"],"answer":[2],"explanation":"知识点为氮肥形态与土壤行为。硝态氮带负电，不被土壤胶体吸附，移动快、肥效快但易淋失，故C正确；肥效慢而持久是铵态氮特点，A错；易被吸附也是铵态氮特点，B错；淹水条件下硝态氮易反硝化损失，D错。"},{"id":226,"type":"single","stem":"烟草大田期发现烟株中下部叶片出现水渍状暗绿斑，并迅速扩展成褐色大斑，叶背有白色霉层，最可能的病害是","options":["烟草黑胫病","烟草赤星病","烟草霜霉病","烟草花叶病"],"answer":[2],"explanation":"知识点为烟草病害症状识别。霜霉病典型症状为叶背白色霉层和水渍状斑，故C正确；黑胫病主要危害茎基部，A错；赤星病病斑有同心轮纹，B错；花叶病以花叶、畸形为主，D错。"},{"id":227,"type":"single","stem":"烤烟成熟采收中，判断下部叶适熟的主要标志是","options":["叶色深绿、叶面平展","叶色黄绿、叶尖下垂","叶色淡黄、主脉变白","叶色橘黄、茸毛脱落"],"answer":[1],"explanation":"知识点为烟叶成熟度判断。下部叶适熟时叶色由深绿转黄绿、叶尖下垂，故B正确；叶色深绿叶面平展为未熟，A错；主脉变白、叶色淡黄多为中上部叶成熟特征，C错；橘黄茸毛脱落为上部叶过熟表现，D错。"},{"id":228,"type":"single","stem":"烟草漂浮育苗池水pH值一般应维持在","options":["4.0~4.5","5.5~6.5","7.5~8.0","8.5~9.0"],"answer":[1],"explanation":"知识点为漂浮育苗水质管理。池水pH 5.5~6.5利于烟苗养分吸收和抑制部分病菌，故B正确；过酸易伤根，A错；偏碱易缺铁锌，C、D错。"},{"id":229,"type":"single","stem":"烟田发现烟株萎蔫、茎基部变黑并有白色霉层，拔起后根系腐烂，下列处置中最合理的是","options":["立即全田灌大水缓解萎蔫","拔除病株并带出田外，病穴撒石灰","保留病株观察是否恢复","仅对病株喷施叶面肥"],"answer":[1],"explanation":"知识点为黑胫病等根茎病害处置。拔除病株、带出田外并处理病穴可减少传染源，故B正确；灌大水会加速病菌传播，A错；保留病株会继续传染，C错；叶面肥不能控制病害，D错。"},{"id":230,"type":"single","stem":"烟叶烘烤变黄期，若烟叶变黄过快且失水过多，正确的调整措施是","options":["提高干球温度并加大通风","降低干球温度并保持湿球温度","提高湿球温度并关闭排气窗","延长变黄时间并停止通风"],"answer":[1],"explanation":"知识点为烘烤变黄期温湿度调控。变黄过快失水多时应降温保湿，缩小干湿差，故B正确；升温加大通风会加速失水，A错；关闭排气窗不解决失水过快，C错；停止通风易积湿但不解决变黄过快，D错。"},{"id":231,"type":"single","stem":"漂浮育苗池水体消毒后，播种前需要确认的关键指标是余氯降至安全范围，通常采用哪种做法最稳妥","options":["用试纸测余氯后直接播种","按消毒时用量的一半再补一次","排空池水重新加清水后播种","静置一夜后不再检测直接播种"],"answer":[2],"explanation":"知识点是漂浮育苗池消毒后残留消毒剂对种子萌发的影响。正确项排空换清水可彻底去除余氯，最稳妥。用试纸测余氯后直接播种看似合理，但试纸精度和取样点差异易误判。按半量补消毒剂会叠加残留，反而更危险。静置一夜不检测无法确认残留是否降到安全范围。"},{"id":232,"type":"single","stem":"烟草育苗盘装基质时，基质含水量以手握成团、轻触即散为宜，其主要作用是","options":["防止基质过湿导致种子缺氧","提高基质装盘后的透气性","保证播种后种子与基质紧密接触","减少基质在运输中的扬尘损失"],"answer":[2],"explanation":"知识点是装盘基质水分与播种质量的关系。手握成团、轻触即散说明水分适中，能保证种子与基质紧密接触利于吸水萌发。防止缺氧是过湿的危害，不是该含水量的主要作用。提高透气性主要靠基质配比和装盘松紧。减少扬尘与含水量关系不大且不是主要目的。"},{"id":233,"type":"single","stem":"烤烟移栽时采用膜下小苗移栽，掏苗放风的时间应主要依据","options":["移栽后天数固定为15天","膜内温度与烟苗长势","烟苗叶片数达到6片","大田杂草开始萌发"],"answer":[1],"explanation":"知识点是膜下小苗移栽掏苗放风的判断依据。应依据膜内温度和烟苗长势，防止高温烧苗或放风过晚徒长。固定天数不考虑天气变化，容易误判。叶片数只是参考之一，不是主要依据。杂草萌发与掏苗时机无直接关系。"},{"id":234,"type":"single","stem":"烟田发现烟株下部叶片出现水渍状暗绿色病斑，迅速扩展并腐烂，有恶臭，最可能的病害是","options":["烟草黑胫病","烟草青枯病","烟草野火病","烟草赤星病"],"answer":[1],"explanation":"知识点是烟草细菌性病害的症状鉴别。青枯病典型症状为水渍状暗绿色病斑、迅速腐烂并有恶臭。黑胫病主要表现为茎基部黑褐色腐烂，无恶臭。野火病病斑有黄晕，不迅速腐烂。赤星病病斑有明显同心轮纹。"},{"id":235,"type":"single","stem":"烟田施用氮肥时，硝态氮与铵态氮配合使用的主要原因是","options":["硝态氮肥效慢需铵态氮补充","铵态氮易流失需硝态氮固定","两者吸收机制不同可协同供应","两者混合可降低肥料成本"],"answer":[2],"explanation":"知识点是烟草氮素营养与肥料配合。硝态氮和铵态氮吸收机制不同，配合使用可协同供应，满足不同生育阶段需求。硝态氮肥效较快，不是慢。铵态氮易被土壤吸附，不是易流失。混合使用与降低成本无直接关系。"},{"id":236,"type":"single","stem":"烟草苗床期发现烟苗叶片发黄、生长缓慢，排除病害后首先应检查的环节是","options":["苗床温度是否偏低","基质pH是否偏碱","播种密度是否过大","光照时间是否不足"],"answer":[0],"explanation":"知识点是苗床期烟苗黄化的常见原因排查。排除病害后，温度偏低是导致发黄生长缓慢的常见原因，应首先检查。pH偏碱也会影响，但不如温度常见。播种密度过大主要导致徒长。光照不足主要导致徒长和叶色淡，但温度更直接。"},{"id":237,"type":"single","stem":"烟田进行地膜覆盖栽培时，覆膜前土壤墒情不足的正确处置是","options":["先覆膜后从膜上打孔灌水","先灌水造墒再覆膜","直接覆膜等待降雨","覆膜后揭开一端灌水再封口"],"answer":[1],"explanation":"知识点是地膜覆盖前的土壤墒情管理。墒情不足应先灌水造墒再覆膜，保证出苗和成活。先覆膜后打孔灌水易造成膜下板结。直接覆膜等雨不可控。覆膜后揭开灌水再封口操作麻烦且效果差。"},{"id":238,"type":"single","stem":"烟草田间管理中，打顶后抹杈的最佳时机是","options":["杈长到10厘米以上时抹除","杈刚长出1至2厘米时抹除","打顶当天一次性抹除","杈长出花序后抹除"],"answer":[1],"explanation":"知识点是打顶后抹杈的适宜时机。杈刚长出1至2厘米时抹除，伤口小、养分消耗少。杈长到10厘米以上消耗养分多且伤口大。打顶当天抹除可能遗漏未萌发的腋芽。杈长出花序后已消耗大量养分。"},{"id":239,"type":"single","stem":"某烟农在烟株团棵期发现田间部分烟株心叶卷曲、叶片增厚变脆，怀疑是病毒病，下一步最合理的处置是","options":["立即全田喷施广谱杀菌剂","拔除病株并防治传毒媒介","增施氮肥促进烟株恢复","全田灌水缓解症状"],"answer":[1],"explanation":"知识点是烟草病毒病的田间处置。病毒病无特效药剂，应拔除病株并防治蚜虫等传毒媒介。喷施杀菌剂对病毒无效。增施氮肥会加重症状。全田灌水不能缓解病毒病。"},{"id":240,"type":"single","stem":"烟叶烘烤过程中，定色期的主要任务是","options":["快速升温促进叶片变黄","稳定温度湿球使叶片干燥定色","降低湿度使叶片完全变黄","高温快速排湿固定颜色"],"answer":[1],"explanation":"知识点是烟叶烘烤各阶段的任务。定色期应稳定温度湿球，使叶片干燥定色。快速升温变黄是变黄期任务。降低湿度完全变黄是变黄后期。高温快速排湿易导致青筋青片。"},{"id":241,"type":"single","stem":"漂浮育苗播种后，苗盘放入苗池初期，营养液深度应控制在","options":["1～2厘米","3～5厘米","6～8厘米","10～12厘米"],"answer":[1],"explanation":"知识点：漂浮育苗苗池水层管理。播种后初期保持3～5厘米水层，利于基质吸水与种子萌发；1～2厘米过浅易使基质吸水不足、盘面干湿不匀；6～8厘米和10～12厘米过深会使基质长期饱和、通透性差，影响出苗与根系生长。"},{"id":242,"type":"single","stem":"烟草苗床期发现烟苗茎基部呈水渍状缢缩、倒伏，湿度大时病部可见白色绵毛状霉层，应首先考虑","options":["猝倒病","黑胫病","赤星病","花叶病"],"answer":[0],"explanation":"知识点：苗期病害症状识别。猝倒病典型症状为茎基部水渍状缢缩、倒伏并生白色绵毛状霉层；黑胫病多发生于大田成株茎基部，呈黑褐色凹陷；赤星病主要为害叶片形成同心轮纹斑；花叶病为病毒病，表现叶片花叶、皱缩，不出现霉层。"},{"id":243,"type":"single","stem":"烤烟移栽时，常规膜下小苗移栽的适宜壮苗标准是","options":["苗龄30天左右、5～6片真叶","苗龄60天左右、10～12片真叶","苗龄90天左右、现蕾期烟苗","苗龄15天左右、2～3片真叶"],"answer":[0],"explanation":"知识点：烟草壮苗标准。膜下小苗移栽要求苗龄30天左右、5～6片真叶，苗高适中、根系发达；苗龄60天、10～12片真叶属常规大苗，不适合膜下小苗移栽；现蕾期烟苗已老化；2～3片真叶苗过小，抗逆性差。"},{"id":244,"type":"single","stem":"烟草大田管理中，打顶后抹杈应及时进行，其主要目的是","options":["减少养分无效消耗、改善田间通风透光","促进腋芽继续生长增加叶片数","降低烟株高度便于机械采收","抑制根系扩展防止倒伏"],"answer":[0],"explanation":"知识点：打顶抹杈的作用。打顶后腋芽萌发会消耗大量养分并影响中上部叶开片，及时抹杈可减少养分无效消耗、改善通风透光；抹杈是去除腋芽而非促进其生长；降低株高与抑制根系并非抹杈的主要目的。"},{"id":245,"type":"single","stem":"烟草黑胫病在田间扩展迅速时，下列处置顺序中最合理的是","options":["先拔除病株带出田外，再对病穴及周围土壤施药","先对全田灌大水，再拔除病株","先追施速效氮肥，再拔除病株","先摘除病叶，再对全田喷施叶面肥"],"answer":[0],"explanation":"知识点：黑胫病田间应急处置。正确顺序是及时拔除病株并带出田外销毁，减少菌源，再对病穴及周围土壤施药控制蔓延；灌大水会加速病原随水传播；追施速效氮肥会加重发病；摘除病叶对茎基部病害无效。"},{"id":246,"type":"single","stem":"烤烟移栽后遭遇持续低温阴雨，烟苗出现发黄、生长停滞，最可能的原因是","options":["根系吸收能力下降导致营养供应不足","土壤水分过多引起缺铁","低温直接杀死叶片细胞","光照不足使烟株进入休眠"],"answer":[0],"explanation":"知识点：低温阴雨对烟苗的影响。低温阴雨使土壤温度低、根系活力下降，吸收养分能力减弱，烟苗表现发黄、生长停滞；缺铁多表现为新叶脉间失绿；低温一般不会直接杀死叶片细胞；烟株不会因此进入真正休眠。"},{"id":247,"type":"single","stem":"烟草大田期发现烟株顶部叶片呈暗绿色、叶尖叶缘向下卷曲，且下部叶片早衰，最可能缺乏的元素是","options":["磷","氮","钾","钙"],"answer":[2],"explanation":"知识点：烟草缺素症状识别。缺钾时上部叶片暗绿、叶尖叶缘向下卷曲，下部叶片早衰；缺磷多表现下部叶片暗绿或紫红；缺氮全株黄化、下部叶先黄；缺钙多表现顶芽和幼叶畸形坏死。"},{"id":248,"type":"single","stem":"烟草育苗中，采用烟种催芽播种时，催芽温度应控制在","options":["15～18℃","20～23℃","25～28℃","32～35℃"],"answer":[2],"explanation":"知识点：烟草催芽温度。烟种催芽适宜温度为25～28℃，利于发芽整齐；15～18℃偏低发芽缓慢；20～23℃发芽不整齐；32～35℃偏高易使胚根受伤、发芽率下降。"},{"id":249,"type":"single","stem":"烤烟田间管理中，烟株现蕾后打顶的适宜时期是","options":["花蕾出现后立即打顶","花蕾伸长期至开花初期","盛花期后打顶","蒴果形成后打顶"],"answer":[1],"explanation":"知识点：打顶时期。烤烟适宜打顶时期为花蕾伸长期至开花初期，此时打顶可兼顾产量与品质；花蕾刚出现即打顶过早，影响上部叶开片；盛花期和蒴果期打顶过晚，养分已大量消耗。"},{"id":250,"type":"single","stem":"漂浮育苗播种后，营养池水面覆盖无纺布的主要作用是","options":["保持盘面湿度并减少藻类滋生","提高池水温度并防止烟苗徒长","固定育苗盘位置并防止漂移","隔绝空气以减少养分挥发"],"answer":[0],"explanation":"知识点：漂浮育苗覆盖管理。正确项对：无纺布可保湿、遮光，抑制藻类。错误项一：提高池水温度并非覆盖无纺布的主要目的，增温多靠棚膜；错误项二：固定苗盘不是无纺布功能；错误项三：隔绝空气以减少养分挥发说法不成立，养分在池水中并非靠覆盖无纺布防挥发。"},{"id":251,"type":"single","stem":"烟草苗床期发现烟苗茎叶徒长、叶色淡绿，最可能的管理原因是","options":["苗床氮肥偏多且光照不足","苗床磷钾肥偏多且通风过强","苗床水分偏少且温度偏低","苗床播种过密且间苗偏早"],"answer":[0],"explanation":"知识点：苗床徒长成因。正确项对：氮肥多、光照弱、湿度大易徒长。错误项一：磷钾偏多、通风强一般不会致徒长；错误项二：水分少温度低会使苗生长受抑而非徒长；错误项三：播种过密虽影响苗质，但间苗偏早不是徒长主因。"},{"id":252,"type":"single","stem":"烟草移栽时采用地膜覆盖，膜孔封土不严最易导致","options":["膜下高温烧苗且杂草从孔口丛生","膜内水汽外逸且地温明显下降","烟苗茎基部受膜口摩擦折断","土壤养分随雨水从孔口流失"],"answer":[0],"explanation":"知识点：地膜覆盖移栽封孔。正确项对：孔口不封，膜下热气从孔口集中逸出易灼苗，同时杂草易从孔口长出。错误项一：膜内水汽外逸不是主要危害，地温也不会因此明显下降；错误项二：膜口摩擦折断不是封土不严的典型后果；错误项三：养分流失与封孔不严关系不大。"},{"id":253,"type":"single","stem":"烤烟大田期追施钾肥时，下列做法更有利于提高钾肥利用效果的是","options":["在烟株团棵期结合中耕深施并覆土","在烟株现蕾期撒施于地表","在烟株旺长期随大水漫灌冲施","在烟株成熟期叶面喷施高浓度钾"],"answer":[0],"explanation":"知识点：钾肥施用时期与方法。正确项对：团棵期需钾量大，深施覆土减少流失。错误项一：现蕾期地表撒施易流失且吸收有限；错误项二：大水漫灌冲施易淋失，且旺长后期大量施钾不当时；错误项三：成熟期叶面高浓度钾易伤叶，且对产量质量作用有限。"},{"id":254,"type":"single","stem":"烟草黑胫病在田间开始发病后，下列处置顺序较合理的是","options":["先拔除病株带出田外，再对病穴及周围施药","先对全田灌水，再拔除病株并深埋","先对病株喷药，再保留病株观察","先追施氮肥促长，再拔除病株"],"answer":[0],"explanation":"知识点：黑胫病田间处置。正确项对：先清除病株并带出田外，再处理病穴和周围，减少传染源。错误项一：先灌水会利于病菌传播；错误项二：保留病株会继续传染；错误项三：追氮促长不能控病，还可能加重。"},{"id":255,"type":"single","stem":"烟草育苗中，采用湿润育苗比漂浮育苗更需要注意的管理环节是","options":["苗盘基质水分补充与盘面通气","营养池水位恒定与池水消毒","苗盘漂浮方向与池面覆盖","池水盐度调节与藻类控制"],"answer":[0],"explanation":"知识点：湿润育苗与漂浮育苗区别。正确项对：湿润育苗靠浇水或底部润灌，需关注基质水分和通气。错误项一：营养池水位恒定是漂浮育苗重点；错误项二：漂浮方向与池面覆盖偏漂浮育苗；错误项三：池水盐度与藻类控制也偏漂浮育苗。"},{"id":256,"type":"single","stem":"烟田发现烟蚜数量上升，释放瓢虫进行生物防治时，下列做法正确的是","options":["在蚜虫发生初期低密度时尽早释放","在蚜虫暴发高峰期一次性大量释放","在刚喷过广谱杀虫剂后立即释放","在正午强光高温时集中释放"],"answer":[0],"explanation":"知识点：生物防治释放时机。正确项对：早期低密度释放，瓢虫易建立种群控蚜。错误项一：暴发期一次性释放难控且成本高；错误项二：刚喷广谱药会杀死瓢虫；错误项三：正午高温强光不利瓢虫活动存活。"},{"id":257,"type":"single","stem":"烟叶采收后，为减少烤房内青杂气，装烟时较合理的做法是","options":["按成熟度分类装烟，同层同质","将欠熟与过熟叶混装同层","将上部叶与下部叶混装同层","将病叶与好叶混装同层"],"answer":[0],"explanation":"知识点：采收装烟分类。正确项对：成熟度一致便于同层同质烘烤。错误项一：欠熟过熟混装难同步变黄定色；错误项二：上下部叶混装含水与厚度差异大；错误项三：病叶混装易传染并影响品质。"},{"id":258,"type":"single","stem":"烟草苗床期遇到连续阴雨，苗床管理应优先采取的措施是","options":["减少浇水并加强通风排湿","增加浇水并密闭保温","增施氮肥并减少通风","提高床温并增加覆盖物"],"answer":[0],"explanation":"知识点：阴雨期苗床管理。正确项对：阴雨湿度大，应控水通风防病防徒长。错误项一：增加浇水密闭会加重病害；错误项二：增氮减通风易徒长感病；错误项三：单纯增温加覆盖不利排湿。"},{"id":259,"type":"single","stem":"烤烟大田期发现烟株下部叶出现水渍状暗绿斑并迅速扩展，田间湿度大，首先应怀疑","options":["烟草黑胫病","烟草花叶病","烟草赤星病","烟草野火病"],"answer":[0],"explanation":"知识点：黑胫病症状识别。正确项对：黑胫病常从下部叶或茎基开始，水渍状暗绿斑，高湿扩展快。错误项一：花叶病以花叶、皱缩为主；错误项二：赤星病多为褐色圆斑；错误项三：野火病多为角斑周围黄晕。"},{"id":260,"type":"single","stem":"烟草移栽时，地温稳定通过多少度方可进行露地移栽","options":["8℃","10℃","15℃","18℃"],"answer":[2],"explanation":"知识点：烟草移栽温度指标。烟苗根系在15℃以上才能正常生长，故露地移栽要求5cm地温稳定通过15℃。8℃和10℃偏低，根系停止生长；18℃虽安全但会推迟移栽适期，影响上部叶充分成熟。"},{"id":261,"type":"single","stem":"烤烟大田管理中，打顶后抹杈应在腋芽长到多长以前完成","options":["3cm","5cm","8cm","10cm"],"answer":[0],"explanation":"知识点：打顶抹杈技术。腋芽长到3cm以前抹除，此时芽体小、伤口小、对叶片损伤轻。5cm时已消耗部分养分；8cm和10cm时腋芽已木质化，抹除费工且伤口大易感病。"},{"id":262,"type":"single","stem":"烟草育苗中，假植的作用是","options":["降低苗床温度防止徒长","促进侧根发生、培育壮苗","杀灭床土中的病原菌","提高种子发芽率"],"answer":[1],"explanation":"知识点：假植的育苗学意义。假植通过切断主根促进侧根大量发生，使烟苗根系发达、移栽后成活快。降低温度防徒长是控水控温措施；杀灭病原菌是床土消毒的作用；提高发芽率是催芽处理的作用。"},{"id":263,"type":"single","stem":"烟田施用铵态氮肥时，以下做法正确的是","options":["与草木灰混合施用","深施覆土后浇水","撒施于地表后不覆土","与石灰同时施入"],"answer":[1],"explanation":"知识点：铵态氮肥施用技术。铵态氮肥深施覆土可减少氨挥发损失。与草木灰混合会因碱性导致氨挥发；撒施不覆土氨挥发严重；与石灰同施同样加速氨挥发。"},{"id":264,"type":"single","stem":"烤烟移栽后还苗期的水分管理目标是","options":["保持土壤湿润促进成活","控制水分促进根系下扎","大量灌水加速生长","保持干旱抑制病害"],"answer":[0],"explanation":"知识点：还苗期水分管理。移栽后烟苗根系受损，保持土壤湿润才能促进新根发生和成活。控水促根下扎是伸根期措施；大量灌水易沤根；干旱会延长还苗期甚至死苗。"},{"id":265,"type":"single","stem":"烟草花叶病在田间的初侵染源主要是","options":["土壤中越冬的卵孢子","带毒烟苗和病残体","越冬的蚜虫成虫","杂草上的锈孢子"],"answer":[1],"explanation":"知识点：烟草花叶病侵染循环。TMV初侵染源主要是带毒烟苗和土壤中病残体。卵孢子是疫霉等卵菌的越冬形式；蚜虫传播的是黄瓜花叶病毒；锈孢子是锈菌的孢子，与花叶病无关。"},{"id":266,"type":"single","stem":"烟田起垄时，垄体高度一般应达到","options":["10～15cm","15～20cm","25～30cm","35～40cm"],"answer":[2],"explanation":"知识点：烟田起垄规格。垄高25～30cm有利于排水防涝、增厚活土层、促进根系发育。10～15cm和15～20cm垄体过矮，雨季易积水；35～40cm过高，抗旱能力差且易倒伏。"},{"id":267,"type":"single","stem":"烤烟成熟采收中，判断下部叶成熟的主要依据是","options":["叶面出现黄斑、叶尖下垂","叶色由绿转黄绿、主脉发白","叶片完全枯黄、叶柄干缩","叶面出现成熟斑、茸毛脱落"],"answer":[1],"explanation":"知识点：烟叶成熟采收标准。下部叶成熟时叶色由绿转黄绿、主脉发白。叶面黄斑叶尖下垂是上部叶过熟表现；完全枯黄叶柄干缩是过熟；成熟斑和茸毛脱落是中部叶成熟特征。"},{"id":268,"type":"single","stem":"某烟农发现苗床烟苗茎叶徒长、叶色淡绿，最可能的原因是","options":["苗床温度偏低","氮肥偏多且光照不足","苗床湿度偏低","播种密度偏稀"],"answer":[1],"explanation":"知识点：烟苗徒长的原因诊断。氮肥偏多配合光照不足会导致茎叶徒长、叶色淡绿。温度偏低抑制生长；湿度偏低导致苗矮小；播种过稀不会引起徒长。"},{"id":269,"type":"single","stem":"烟草漂浮育苗中，播种后覆盖池膜的主要目的是保持苗池温湿度并促进出苗，当幼苗子叶完全展开并开始出现第一片真叶时，正确的揭膜做法是","options":["晴天上午先揭膜两端通风炼苗，傍晚再盖回，连续几天后择晴天上午全部揭膜","晴天中午气温最高时一次性把膜全部揭掉，让幼苗快速适应外界环境","阴雨天温度较低时揭膜，避免晴天揭膜造成幼苗失水萎蔫","傍晚气温下降后揭膜，揭后立即喷施一次杀菌剂保护幼苗"],"answer":[0],"explanation":"知识点：漂浮育苗揭膜炼苗程序。正确项先通风炼苗再逐步揭膜，可避免幼苗骤然失水。晴天中午一次性揭膜温差大、易灼伤萎蔫；阴雨天揭膜温度低、湿度大，幼苗适应差且易感病；傍晚揭膜后夜间低温，幼苗易受冷害且喷药时机不当。"},{"id":270,"type":"single","stem":"烟草移栽时，确定移栽深度的核心依据是保证烟苗茎基部埋入土中适宜深度，下列做法中符合常规要求的是","options":["将烟苗茎基部埋入土中约3厘米，使生长点露出地面","将烟苗全部茎叶埋入土中，只留顶端两片叶","将烟苗根系放在土表，再用土堆成小丘覆盖根部","将烟苗茎基部埋入土中约10厘米，促进不定根大量发生"],"answer":[0],"explanation":"知识点：烟草移栽深度。正确项茎基部埋入约3厘米，既能促发不定根又不埋没生长点。全部埋入茎叶会使生长点窒息；根系放土表再堆土，根系悬空易失水；埋深10厘米会抑制生长点、缓苗慢。"},{"id":271,"type":"single","stem":"烤烟大田管理中，追肥施用时机和位置对肥效影响很大，下列追肥做法正确的是","options":["在烟株最大叶尖垂直投影处开穴或开沟深施后覆土","紧贴烟株茎基部撒施，随后不覆土让其自然溶解","在行间均匀撒施，随后大水漫灌使肥料渗入土中","在烟株顶部叶片上喷施，利用叶片直接吸收养分"],"answer":[0],"explanation":"知识点：烟草追肥位置。正确项在最大叶尖投影处深施覆土，此处为根系密集区，肥效高。紧贴茎基撒施不覆土易烧苗且养分挥发；行间撒施后大水漫灌会造成养分流失和根系上浮；顶部叶面喷施只能补充微量营养，不能替代根部追肥。"},{"id":272,"type":"single","stem":"烟草黑胫病在田间常从茎基部开始发病，下列农业防治措施中针对性最强的是","options":["实行轮作并选用抗病品种，及时拔除病株并带出田外销毁","增施氮肥促进烟株快速生长，以旺盛长势抵抗病菌侵入","雨后及时中耕松土，降低土壤湿度并切断部分根系","将病株拔除后就地丢弃在烟田行间，让其自然腐烂"],"answer":[0],"explanation":"知识点：烟草黑胫病农业防治。正确项轮作、抗病品种和清除病株是针对性最强的综合措施。偏施氮肥会使烟株抗性下降；中耕松土虽有利但非针对黑胫病核心措施；病株就地丢弃会使病菌继续在田间扩散。"},{"id":273,"type":"single","stem":"烟草蚜虫是传播马铃薯Y病毒的重要媒介，在蚜虫迁飞高峰期防治时，下列做法最合理的是","options":["在蚜虫迁飞高峰前及时喷药，并清除田边越冬寄主","等蚜虫大量发生后再喷药，此时虫体大更容易被杀死","只在烟株顶部喷药，因为蚜虫主要聚集在嫩叶上","用高浓度药液灌根，通过根系吸收来杀灭地上蚜虫"],"answer":[0],"explanation":"知识点：蚜虫防治与病毒病预防。正确项在迁飞高峰前防治并清除越冬寄主，可减少传毒机会。等大量发生后再治已造成病毒传播；只喷顶部不能覆盖全株；灌根对地上部蚜虫效果差且不经济。"},{"id":274,"type":"single","stem":"烟草苗床期出现烟苗徒长、茎细叶薄的现象，下列管理措施中最直接有效的是","options":["适当降低苗床温度并增加光照，同时控制氮肥和水分","进一步提高苗床温度，促进烟苗加快生长赶上季节","增施氮肥并勤浇水，让烟苗在移栽前尽快长高","将苗床遮阴覆盖，减少光照以抑制烟苗纵向生长"],"answer":[0],"explanation":"知识点：烟苗徒长的调控。正确项降温、增光、控氮控水可抑制徒长、培育壮苗。提高温度会加剧徒长；增氮浇水使徒长更严重；遮阴会加重茎细叶薄，不利于壮苗。"},{"id":275,"type":"single","stem":"烟草移栽后遭遇持续干旱，烟苗出现萎蔫，此时最适宜采取的补水方式是","options":["在烟株附近开穴浇足定根水，待水下渗后覆土保墒","全田大水漫灌，让水层淹没畦面后再排干","只向叶片喷水，不浇根部以免降低地温","等降雨后再补浇，避免浇水后土壤板结"],"answer":[0],"explanation":"知识点：干旱期烟苗补水。正确项开穴浇足定根水并覆土保墒，可提高成活率。大水漫灌易板结、地温骤降且浪费水；只喷叶片不能补充根区水分；等雨会延误缓苗甚至死苗。"},{"id":276,"type":"single","stem":"烟草打顶后，为控制腋芽生长并保证上部叶开片，下列做法正确的是","options":["打顶后及时抹去腋芽，或使用抑芽剂定向涂抹在叶腋处","打顶后保留顶部2至3个腋芽，让其长成侧枝增加叶片数","打顶后不处理腋芽，任其自然生长以分散植株养分","打顶后立即全田喷施高浓度抑芽剂，包括叶片正反面"],"answer":[0],"explanation":"知识点：打顶后腋芽控制。正确项及时抹芽或定向涂抑芽剂，可集中养分供上部叶。保留腋芽会消耗养分、降低上部叶质量；不处理腋芽同样消耗养分；全田喷高浓度抑芽剂易造成药害。"},{"id":277,"type":"single","stem":"烟草漂浮育苗池水pH值偏高时，烟苗容易出现缺铁黄化，下列调控措施中正确的是","options":["适量加入酸性物质调节池水pH至适宜范围，并检查营养液配比","大量加入石灰水提高pH，以沉淀水中杂质","直接更换为井水，不再调节pH和营养液浓度","向池水中加入大量碱性肥料，促进烟苗对铁的吸收"],"answer":[0],"explanation":"知识点：漂浮育苗池水pH调控。正确项适量酸化并检查营养液，可提高铁的有效性。加石灰水会进一步提高pH，加重缺铁；换井水不调pH不能解决问题；加碱性肥料会使缺铁更严重。"},{"id":278,"type":"single","stem":"烟草田间发现烟株叶片出现花叶、皱缩且叶脉坏死，怀疑是病毒病，下列处置措施中最恰当的是","options":["及时拔除病株并带出田外销毁，同时防治蚜虫等传毒媒介","保留病株观察症状变化，待确认后再决定是否拔除","对病株喷施杀菌剂，控制病毒继续在株内扩散","增施氮肥促进烟株恢复，同时减少田间操作"],"answer":[0],"explanation":"知识点：烟草病毒病田间处置。正确项拔除病株并防治传毒媒介，可减少毒源和传播。保留病株会成为传染源；杀菌剂对病毒无效；增施氮肥不能治病毒，且操作可能加剧传播。"},{"id":279,"type":"single","stem":"某烟农在烟叶采收前发现下部叶已适熟，但中部叶尚欠熟，正确的采收安排是","options":["先采收下部适熟叶，中部叶待成熟后再分批采收","将下部叶和中部叶一次性全部采完，便于统一烘烤","只采中部叶，下部叶留到全部成熟后一起采","暂不采收，等全部叶片成熟后一次性采收完毕"],"answer":[0],"explanation":"知识点：烟叶成熟采收原则。正确项分批采收成熟叶，保证各部位叶烘烤质量。一次性采完会使欠熟叶和过熟叶混烤，质量下降；只采中部叶浪费下部适熟叶；等全部成熟会使下部叶过熟。"},{"id":280,"type":"multi","stem":"烟草大田期进行中耕培土时，下列操作要求正确的有","options":["中耕深度应掌握先浅后深再浅的原则，避免伤根","培土应在烟株旺长前完成，将行间土培向茎基部","中耕可结合除草进行，但应避免在雨后土壤过湿时作业","培土高度越高越好，最好将下部叶片全部埋入土中","中耕后立即大水漫灌，使土壤沉实便于根系生长"],"answer":[0,1,2],"explanation":"知识点：烟草中耕培土技术要求。正确项包括先浅后深再浅、旺长前培土、结合除草且避开过湿作业。培土过高埋叶会影响光合和诱发病害；中耕后立即大水漫灌易板结且不利根系呼吸。"},{"id":281,"type":"single","stem":"漂浮育苗播种后，营养池水面与格盘底面之间应保持的合适间隙是","options":["紧密贴合不留空隙","保持0.5~1厘米间隙","保持3~5厘米间隙","保持8~10厘米间隙"],"answer":[1],"explanation":"知识点是漂浮育苗营养池的水位控制。正确项保持0.5~1厘米间隙可使基质通过毛细管吸水又不至于淹没种子。紧密贴合不留空隙易造成基质过湿缺氧；3~5厘米间隙则基质吸水不足、出苗不齐；8~10厘米间隙远超毛细吸水高度，种子无法获得水分。"},{"id":282,"type":"single","stem":"烟草苗床期发现烟苗茎基部缢缩、倒伏，茎基表面有白色棉絮状物，最可能是","options":["猝倒病","炭疽病","黑胫病","病毒病"],"answer":[0],"explanation":"知识点是苗期主要病害症状识别。猝倒病典型症状即茎基部缢缩倒伏并生白色棉絮状霉层。炭疽病表现为叶片产生褐色凹陷病斑而非茎基缢缩；黑胫病多发生于大田成株，茎基变黑；病毒病主要表现为花叶、畸形，不产生白色霉层。"},{"id":283,"type":"single","stem":"烟草移栽时采用地膜覆盖，膜孔封土的主要作用是","options":["防止膜内杂草顶破地膜","防止高温灼伤烟苗茎叶","减少膜内水汽外逸并抑制杂草","便于追肥时肥料落入膜内"],"answer":[2],"explanation":"知识点是地膜覆盖移栽的封土作用。正确项封土可压紧膜口减少水汽散失并抑制膜内杂草生长。防杂草顶膜只是封土部分作用而非主要目的；封土不能防止高温灼伤；追肥仍需揭膜或打孔，封土不便于肥料落入。"},{"id":284,"type":"single","stem":"烤烟大田期打顶后，顶部烟杈反复萌发，最有效的控制措施是","options":["打顶后立即深中耕断根","打顶时留叶过多任其生长","打顶后及时抹杈并使用抑芽剂","打顶后大量灌水促进上部叶开片"],"answer":[2],"explanation":"知识点是打顶抹杈与抑芽技术。打顶后及时抹杈并配合使用抑芽剂可有效控制腋芽萌发。深中耕断根主要在团棵期进行，与抑芽无直接关系；留叶过多会加剧烟杈生长；灌水促进开片不能抑制烟杈，反而助长其萌发。"},{"id":285,"type":"single","stem":"烟草育苗中，剪叶的主要目的是","options":["减少叶片数量以降低蒸腾","控制烟苗徒长并促进茎秆粗壮","去除病叶以防病害传播","增加苗床通风以降低湿度"],"answer":[1],"explanation":"知识点是剪叶的培育壮苗作用。剪叶通过去除部分叶面积调控生长，控制徒长、促进茎秆粗壮和根系发达。减少蒸腾不是剪叶的主要目的；去除病叶属于卫生操作而非剪叶本意；增加通风是间苗、揭膜等措施的作用。"},{"id":286,"type":"single","stem":"烟草黑胫病在田间传播蔓延的主要途径是","options":["空气飞沫短距离传播","雨水和灌溉水携带病菌传播","蚜虫取食汁液传播","种子表面携带病菌传播"],"answer":[1],"explanation":"知识点是黑胫病的传播途径。黑胫病病菌借助雨水、灌溉水在土壤中传播，是田间流行的主要方式。空气飞沫不是其主要传播方式；蚜虫主要传播病毒病；种子带菌不是黑胫病田间蔓延的主要途径。"},{"id":287,"type":"single","stem":"烟田施用氮肥过多时，烟株最可能出现的表现是","options":["叶片小而厚、成熟提前","叶色浓绿、贪青晚熟","茎秆细弱、叶片发黄","下部叶过早枯黄脱落"],"answer":[1],"explanation":"知识点是氮素营养与烟株长相的关系。氮肥过多使烟株叶色浓绿、贪青晚熟、品质下降。叶片小而厚成熟提前多为缺氮或后期脱肥表现；茎秆细弱叶片发黄常与缺钾或缺氮有关；下部叶过早枯黄多与缺氮或早衰有关。"},{"id":288,"type":"single","stem":"烟草移栽后遭遇持续低温阴雨，最易诱发的苗期病害是","options":["黑胫病","猝倒病","赤星病","蛙眼病"],"answer":[1],"explanation":"知识点是低温阴雨与苗期病害的关系。持续低温阴雨、苗床湿度大时猝倒病最易流行。黑胫病多在大田高温高湿条件下发生；赤星病和蛙眼病主要为害大田成株叶片，与苗期低温阴雨关系不密切。"},{"id":289,"type":"single","stem":"烟草苗床播种后覆盖遮阳网，其主要目的是","options":["防止鸟兽啄食种子","降低床面温度并保持水分","增加光照促进光合作用","防止雨水冲刷造成板结"],"answer":[1],"explanation":"知识点是遮阳网在育苗中的作用。遮阳网可降低床面温度、减少水分蒸发，利于出苗。防鸟兽啄食不是遮阳网的主要功能；遮阳网会减弱光照而非增加；防雨水冲刷主要靠覆盖措施而非遮阳网。"},{"id":290,"type":"single","stem":"某烟农在团棵期发现烟株叶片呈暗绿色并伴有叶缘上卷，最可能缺乏的元素是","options":["氮","磷","钾","钙"],"answer":[2],"explanation":"知识点是缺钾症状识别。缺钾时叶片暗绿、叶缘上卷，后期叶尖叶缘出现枯斑。缺氮表现为叶色变淡发黄；缺磷表现为叶色暗绿但多伴下部叶发紫；缺钙主要表现为顶芽和幼叶受害。"},{"id":291,"type":"single","stem":"漂浮育苗播种后，苗池水温持续低于适宜范围时，最直接影响的生理过程是","options":["种子吸水膨胀速度","胚根突破种皮的细胞分裂","幼苗叶片的光合产物积累","基质中矿质元素的溶解"],"answer":[0],"explanation":"知识点为漂浮育苗水温对萌发的影响。水温偏低时种子吸水膨胀速度明显减慢，是出苗延迟的首要原因；胚根突破种皮更多受基质湿度和氧气影响；光合产物积累是出苗后叶片功能，与播种初期水温关系不大；矿质元素溶解受水温影响较小且不是出苗延迟的主因。"},{"id":292,"type":"single","stem":"烤烟移栽时，烟苗茎秆过高、叶片数偏多，正确的处理方式是","options":["深栽至只露出顶部3～4片叶","浅栽使生长点略高于垄面","斜栽使茎秆大部分贴于垄面","原深度移栽后培土至第一叶位"],"answer":[0],"explanation":"知识点为壮苗移栽的深栽原则。高脚苗深栽可促发不定根、降低茎秆外露，故深栽至仅露顶部3～4片叶正确；浅栽使生长点高于垄面会加剧失水和倒伏；斜栽贴垄面易造成茎秆灼伤和根系分布不均；原深度移栽不解决茎秆过长问题，培土至第一叶位仍留过多茎秆。"},{"id":293,"type":"single","stem":"烟草团棵期田间长势偏旺、叶色浓绿，此时最不宜采取的措施是","options":["控制氮肥追施量","适当推迟灌溉时间","喷施多效唑抑制旺长","增施速效氮肥促苗"],"answer":[3],"explanation":"知识点为团棵期水肥调控。长势偏旺叶色浓绿说明氮素已足，继续增施速效氮肥会加剧徒长、推迟成熟，是最不宜措施；控氮、推迟灌溉、喷施多效唑均为常见控旺手段，方向正确。"},{"id":294,"type":"single","stem":"烟田发现少量烟株叶片出现花叶、皱缩，拔除病株后最应紧接着做的是","options":["对周边烟株喷施杀虫剂防蚜","全田追施钾肥增强抗性","对病穴土壤撒石灰消毒","将拔除病株带出田外深埋"],"answer":[3],"explanation":"知识点为烟草病毒病田间处置。花叶皱缩多为病毒病，蚜虫是传播介体，但拔除病株后首要环节是清除传染源，即把病株带出田外深埋；喷施杀虫剂防蚜应在清除病株之后进行；追施钾肥和撒石灰均不能直接切断毒源，顺序上不是紧接着的首要动作。"},{"id":295,"type":"single","stem":"烟草苗床期进行间苗定苗时，正确的操作顺序是","options":["先定苗后间苗再补苗","先间苗后定苗再补苗","先补苗后间苗再定苗","先间苗后补苗再定苗"],"answer":[1],"explanation":"知识点为苗床间苗定苗程序。应先拔除过密弱苗（间苗），再按密度留足壮苗（定苗），最后对缺苗处补栽（补苗）；先定苗会造成密度不准，先补苗再间苗易把补的苗间掉，顺序均不合理。"},{"id":296,"type":"single","stem":"烟草大田期遭遇持续降雨后，田间出现积水，最优先的处置是","options":["立即追施速效氮肥促恢复","喷施广谱杀菌剂预防病害","尽快排除积水并中耕松土","覆盖地膜减少水分蒸发"],"answer":[2],"explanation":"知识点为涝害应急管理。积水首先导致根系缺氧，应尽快排除积水并中耕松土改善通气；此时追施氮肥会加重根系负担；喷杀菌剂是后续预防措施而非最优先；覆盖地膜会阻碍散墒，方向相反。"},{"id":297,"type":"single","stem":"烟草育苗中，采用湿润育苗时基质含水量应保持在","options":["手捏成团、指缝不滴水","手捏成团、指缝明显滴水","手捏散开、呈干燥粉末状","手捏成团、松手即散开"],"answer":[0],"explanation":"知识点为湿润育苗基质水分标准。适宜含水量为手捏成团、指缝不滴水；指缝滴水说明过湿易烂根；手捏散开呈粉末状为过干；手捏成团松手即散说明偏干，均不符合湿润育苗要求。"},{"id":298,"type":"single","stem":"烟草移栽后遭遇低温，烟苗出现轻微冻害，正确的补救措施是","options":["立即大量灌水提高地温","追施速效氮肥促进生长","喷施磷酸二氢钾并中耕提温","拔除受冻苗重新补栽"],"answer":[2],"explanation":"知识点为冻害补救。轻微冻害后应喷施磷酸二氢钾增强抗逆并中耕提温；大量灌水会降低地温加重冷害；追施速效氮肥会刺激旺长降低抗性；轻微冻害不必拔苗重栽，拔苗反造成缺苗。"},{"id":299,"type":"single","stem":"烟草漂浮育苗中，当烟苗出现茎叶徒长、根系发黄且盘旋于基质表面时，最可能的原因是","options":["苗盘底距营养液面过高","营养液浓度偏高且光照不足","基质装盘过松且播种过深","剪叶次数过多且通风过强"],"answer":[1],"explanation":"知识点为漂浮育苗苗床管理。营养液浓度偏高会抑制根系下扎、促使茎叶徒长，加之光照不足则更易出现高脚苗和根系盘面；正确项对。苗盘底距液面过高会导致根系下扎不足而干燥，但不会茎叶徒长；基质装盘过松、播种过深主要影响出苗整齐度；剪叶过多、通风过强会抑制徒长而非造成徒长。"},{"id":300,"type":"multi","stem":"烟叶成熟采收期，中部烟叶出现叶面有黄斑、主脉发白、叶尖下垂且茸毛脱落，判断为适熟；此时田间若遇连续降雨，正确的采烤处置有","options":["抢在雨前采收适熟叶并单独装炕","雨后立即采收所有成熟叶并加大装炕密度","雨后等叶面水分散失后再采并适当稀装","对已过熟叶先采并单独编竿上炕","降雨期间继续采收并直接堆放在炕房外"],"answer":[0,2,3],"explanation":"知识点为成熟采收与雨天处置。雨前抢采适熟叶可减少淋溶和返青，单独装炕便于控水；雨后待叶面水分散失再采、适当稀装利于排湿；已过熟叶先采单独编竿可避免与适熟叶同炕造成烤青或糟片。雨后立即采所有成熟叶并加大装炕密度会因湿叶堆积导致糟片；降雨期间采收堆在炕房外会造成叶片发热变质。"}]}