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1、本科生毕业论文（设计）题目：不同光照条件下渍水对玉米幼苗光合和生长的影响学院:专业班级：学生姓名：指导教师：撰写日期：不同光照条件下渍水对玉米幼苗光合和生长的影响（）摘要：玉米苗期耐旱怕涝，苗期土壤水分过多往往对玉米的生长和产量形成造成不利影响。同时，玉米对淹水的响应还受其他环境因素的影响。本研究以玉米品种郑单958为试材，探讨了两种不同光照条件下玉米幼苗对淹水的响应差异。结果发现，在相对较高的光照条件下，淹水导致净光合速率、蒸腾速率和水分利用效率分别降低70％，26％和59％；叶绿素a，叶绿素b和叶绿素
2、a+b分别降低31％，42％和34％；地下生物量和总生物量分别降低52％和34％。低光强条件下，淹水处理6天的幼苗生物量略有下降。淹水对相对较高光照强度下生长的玉米幼苗的光合速率、生物量和冠根比的影响要明显高于在低光强下生长的玉米幼苗。结果提示，尽管玉米是高光效的C4植物，有着较高的光饱和点，但在淹水胁迫下，相对较高的光照强度仍然加剧了土壤淹水胁迫水浸的影响，而较低的光照强度可以在一定程度上减轻淹水胁迫造成的伤害。因此，我们在研究究淹水对玉米生长发育的影响时，应考虑光强环境的变化。关键字：淹水；光照；玉米
3、；光合速率；冠根比EffectsofSoilFloodingonPhotosynthesisandGrowthofZeamaysL.SeedlingsunderDifferentLightIntensitiesHaochen(CollegeofAgriculture08-cropbiotechnology-1)Abstract:Soilfloodingisoneofthemajorabioticstressesthatrepressmaize(ZeamaysL.)growthandyield,andoth
4、erenvironmentalfactorsofteninfluencesoilfloodingstress.Thispaperreportsanexperimentaltestofthehypothesisthatlightintensitycaninfluencetheresponsesofmaizeseedlingstosoilflooding.Inthisexperiment,maizeseedlingsweresubjectedtosoilfloodingatthetwo-leafstageun
5、dercontrollight(600μmolm-2s-1)orlowlight(150μmolm-2s-1)conditions.Undercontrollightgrowthconditions,theaveragePN,EandWUEwere70%,26%and59%,respectively,higherinnon-floodedthaninfloodedseedlings;andtheaverageChla,Chlb,andChla+bwere31%,42%and34%,respectively
6、,higherinnon-floodedthaninfloodedseedlings;andtheaveragebelowgroundbiomassandtotalbiomasswere52%and34%,respectively,higherinnon-floodedthaninfloodedseedlings.Therewasaslightdecreaseofseedlingbiomassinsixdaysfloodedseedlingsunderlowlightgrowthconditions.Th
7、eeffectsoffloodingonphotosynthetic,seedlinggrowthandshoot/rootratioweremorepronouncedundercontrollightgrowthconditionsthanunderlowlightgrowthconditions,whichindicatethatevenformaizeisC4plant,relativelyhighlightintensitystillaggravatedsoilfloodingstresswhi
8、lelowlightgrowthconditionmitigatedsoilfloodingstress,andsuggestthatlighteffectsshouldbeconsideredwhenwestudymaizeresponsestosoilflooding.Keywords:flood,light,maize,photosynthesisrate,shoot/rootratio在旱地作物生产过程中，涝渍是继干旱
