【作者】 杜建雄；

【导师】 侯向阳； 刘金荣；

【作者基本信息】 甘肃农业大学 ， 草业科学， 2010， 博士

【摘要】 为进一步深入探究硅肥对干旱条件下草坪草生长、生理特性及抗旱性方面的影响,本研究以狗牙根(Cynodon Dactylon L.)、草地早熟禾(Poa pratensis L.)和高羊茅(Festuca arundinacea Scherb.)各一个品种为试验材料,第一阶段对参试3种草坪草进行3种灌水处理(分别按田间最大持水量的100%,75%,50%进行灌水,分别简称FWC100,FWC75,FWC50)45 d,同时对参试3种草坪草分别施加0,28ppm,56ppm,112ppm的硅酸(分别简称Si0,Si28,Si56,Si112)。期间测定了参试3种草坪草的总蒸散量(Evapotranspiration, ET),叶片相对含水量(Relative Water Content, RWC),叶片相对电导率(Electrolyte Leakage, EL),草坪质量(Turf Quality, TQ),超氧化物歧化酶(Superoxide Dismutase, SOD)活性,过氧化氢酶(Catalase, CAT)活性,丙二醛(malondialdehyde, MDA)含量,根干重(Root Dry Weight, RDW)和根活性(Root Activity,RACT)。第二阶段对所有参试草种进行完全复水处理50 d,同时按第一阶段各自对应处理施加0,28ppm,56ppm,112ppm的硅酸,复水结束之后随即进行第三阶段完全干旱处理,由于参试草种高羊茅恢复情况较好,因此以高羊茅为试验材料进行再干旱胁迫处理,干旱胁迫30 d,期间分别测定了叶片相对含水量(RWC)、叶片萎蔫率(LW)、叶片相对电导率(EL)、草坪质量(TQ)、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、丙二醛(MDA)含量,主要结论如下:1.随着灌水量的减少,参试3种草坪草的总蒸散量呈现出下降趋势。施加不同浓度硅肥后,FWC100处理对应参试3种草坪草的总蒸散量并没有发生明显的变化,而FWC75和FWC50处理对应参试3种草坪草的总蒸散量随硅肥浓度的增加呈现出下降趋势,尤其Si56处理对应参试3种草坪草的总蒸散量下降最为明显。2.FWC75和FWC50处理对应参试3种草坪草的RWC较FWC100处理对应参试3种草坪草的RWC出现了明显下降,以FWC50处理对应参试3种草坪草的RWC降低最为明显。施加不同浓度硅肥后,FWC100处理对应参试3种草坪草的RWC基本保持在一个水平,而在FWC75和FWC50灌水条件下,随着硅肥浓度的增加参试3种草坪草的RWC都出现了明显的上升,尤其以Si56处理对应3种草坪草的RWC上升最为明显,硅肥增强了参试3种草坪草的抗旱性。3.在没有施加硅肥处理中,FWC50和FWC75处理对应参试3种草坪草的EL明显高于FWC100处理对应各自草种的EL,尤其FWC50处理对应3种草坪草的EL升高最明显。施加不同浓度硅肥后,FWC100处理对应参试3种草坪草的EL并没有随硅肥浓度的增加而发生明显变化,随着硅肥浓度的增加,FWC75和FWC50处理对应参试3种草坪草的EL出现明显下降,尤其FWC50处理对应参试3种草坪草的EL下降明显,FWC75和FWC50处理对应参试草坪草的EL降幅以Si56处理最为明显。硅肥增强了参试3种草坪草的抗旱性。4.在没有施加硅肥处理中,FWC75和FWC50处理对应参试3种草坪草的TQ较FWC100处理对应各自草坪草的TQ出现了明显下降,即灌水量越少,TQ下降越明显。施加硅肥后,FWC100处理对应参试3种草坪草的TQ并没有随硅肥浓度的增加而发生明显变化,硅肥并没有明显提高草坪草的TQ。而FWC75和FWC50处理对应参试3种草坪草的TQ随着硅肥浓度的增加而明显上升,总体来看以Si56处理各参试草种的TQ上升最为明显,硅肥增强了参试3种草坪草的抗旱性。5.在没有施加硅肥处理中,FWC75和FWC50处理对应参试3种草坪草的SOD和CAT活性明显低于FWC100处理对应参试3种草坪草的SOD和CAT活性,而且灌水量越少,SOD和CAT活性下降越明显。施加硅肥后,FWC100处理对应参试3种草坪草的SOD和CAT活性并没有随硅肥浓度的增加而显著升高,而FWC75和FWC50处理对应参试3种草坪草的SOD和CAT活性随硅肥浓度的增加而明显升高,而且呈现出灌水量越少硅肥提高参试3种草坪草的SOD和CAT活性的效果越明显,尤其Si56处理参试3种草坪草的SOD和CAT活性上升最为明显,硅肥增强了参试3种草坪草的抗旱性。6.在没有施加硅肥处理中,FWC75和FWC50处理对应参试3种草坪草的MDA含量明显高于FWC100处理对应参试3种草坪草的MDA含量,尤其FWC50处理参试3种草坪草的MDA含量上升最明显。施加硅肥后,FWC100处理对应参试3种草坪草的MDA含量并没有随硅肥浓度的增加而发生明显变化,而FWC75和FWC50处理对应参试3种草坪草的MDA含量随硅肥浓度的增加而出现明显下降,尤其以Si56处理对应参试3种草坪草的MDA含量下降最为明显,硅肥增强了参试3种草坪草的抗旱性。7.在没有施加硅肥处理中,FWC75和FWC50处理对应参试3种草坪草的RDW,RACT明显低于FWC100处理对应各自草种的RDW,RACT,而且灌水量越少,参试3种草坪草的RDW,RACT下降越明显。施加硅肥后,FWC100处理对应参试3种草坪草的RDW,RACT并没有随硅肥浓度的增加而明显变化,基本保持在同一水平,而FWC75和FWC50处理对应参试3种草坪草的RDW,RACT随硅肥浓度的增加而明显上升,尤其Si56处理对应参试3种草坪草的RDW,RACT上升最为明显,硅肥增强了参试草坪草的抗旱性。8.复水后再次干旱胁迫下,参试高羊茅的RWC,TQ出现了明显下降,没施加硅肥处理对应高羊茅的RWC,TQ要明显低于施加硅肥处理的。在干旱胁迫下,随着硅肥浓度的增加,参试高羊茅的RWC,TQ逐渐降低,而且施加硅肥处理对应高羊茅的RWC,TQ要高于没施加硅肥处理对应高羊茅的RWC,TQ,相同浓度硅肥FWC100处理对应高羊茅的RWC,TQ低于FWC75和FWC50处理对应高羊茅的RWC,TQ。适当干旱锻炼及硅肥增强了参试高羊茅的抗旱性。9.复水后再次干旱胁迫下,参试高羊茅的EL和LW出现了明显的升高。干旱胁迫结束时(30 d),没施加硅肥处理对应高羊茅的EL和LW较施加硅肥处理的EL和LW高;而且相同浓度硅肥下,FWC50处理对应高羊茅的EL和LW较FWC100和FWC75处理对应高羊茅的EL和LW低,适当干旱锻炼及硅肥增强了参试高羊茅的抗旱性。10.复水后再次干旱胁迫下,参试高羊茅的SOD活性出现了短暂升高,随后出现了明显下降,而CAT活性则持续下降。干旱胁迫结束时(30 d),没施加硅肥对应高羊茅的SOD和CAT活性明显低于施加硅肥高羊茅的SOD和CAT活性;在干旱胁迫下,随着硅肥浓度的增加,参试高羊茅的SOD和CAT活性相对较高,而且相同浓度硅肥处理下,FWC50处理对应高羊茅的SOD和CAT活性较FWC100和FWC75处理对应的SOD和CAT活性高,适当干旱锻炼及硅肥增强了参试高羊茅的抗旱性。11.复水后再次干旱胁迫下,参试高羊茅的MDA含量出现了明显的上升。干旱胁迫结束时(30 d),没施加硅肥对应高羊茅的MDA含量明显高于施加硅肥高羊茅的MDA含量;随着硅肥浓度的增加,参试高羊茅的MDA含量不同程度地下降,而且相同浓度硅肥处理下以FWC50处理对应参试高羊茅的MDA含量较低,干旱胁迫结束时(30 d),Si56处理对应高羊茅的MDA含量相对较低,适当干旱锻炼及硅肥增强了参试高羊茅的抗旱性。更多还原

【Abstract】 In order to study the effects of silicon on growth and physiological characteristic of turfgrass under drought stress, Bermurd, Kentucky bluegrass, and Tall fescue were used as experimental material,and irrigated by three irrigation treatments (irrigating according to 100%, 75%, and 50% of maximum field capacity ) 45 d at the first stage, and at the same time 0, 28ppm, 56ppm, 112ppm silicon acid were applied. Evapotranspiration (ET), leave relative water content (RWC), leave relative electrothye leakage (EL), turf quality (TQ), superoxidation (SOD) activity, catalase (CAT) activity, malondialdehyde (MDA) content, root dry weight (RDW), and root activity (RACT) were determined during the experiment. At the second stage, all tested cultivars were rewatered fully 50 d, and meanwhile 0, 28ppm, 56ppm, 112ppm silicon acid were applied, following rewatering, the third stage drought stress treatment began, Tall fescue could recover best, and then was made as trial material to expose drought stress 30 d, during drought stress RWC, EL, LW, TQ, SOD, CAT, and MDA were determined. Main conclusions as following:1. Under three irrigation conditions, ET of three tested turfgrasses showed decreasing trend with decreasing irrigation content. Following different concentration silicon fertilizer were applied, ET of three tested turfgrasses for FWC100 treatment did not change markedly, while ET of three tested turfgrasses for FWC75 and FWC50 declined with increasing silicon fertilizer concentration, especially, ET of three tested turfgrasses for FWC50 declined markedly.2. RWC of three tested turfgrasses for FWC75 and FWC50 decreased more markedly than that of three tested turfgrasses for FWC100, RWC of three tested turfgrasses for FWC50 declined most markedly. Following different concentration silicon fertilizer were applied, RWC of three tested turfgrasses for FWC100 hardly kept the same level, RWC of three tested turfgrasses for FWC75 and FWC50 increased markedly with increasing silicon fertilizer concentration, especially RWC of three tested turfgrasses for FWC50 increased most markedly. Silicon fertilizer can enhance drought resistance of tested turfgrasses.3. At un-silicon fertilizer treatment, EL of three tested turfgrasses for FWC75 and FWC50 was higher than that of three tested turfgrasses for FWC100, especially EL of three tested turfgrasses for FWC50 increased most markedly. Following different concentration silicon fertilizer were applied, EL of three tested turfgrasses for FWC100 treatment did not change markedly with increasing silicon fertilizer concentration, while EL of three tested turfgrasses for FWC75 and FWC50 decreased markedly, especically EL of three tested turfgrasses for FWC50 declined most markedly, and EL of three tested turfgrasses for FWC50 and FWC75 decreased obviously under Si56 treatment. Silicon fertilizer can enhance drought resistance of tested turfgrasses.4. At un-silicon fertilizer treatment, TQ of three tested turfgrasses for FWC75 and FWC50 decreased more markedly than that of three tested turfgrasses for FWC100, less irrigation water, lower TQ. Following different concentration silicon fertilizer were applied, TQ of three tested turfgrasses for FWC100 treatment did not change markedly with increasing silicon fertilizer concentration, silicon could not improve TQ. While TQ of three tested turfgrasses for FWC75 and FWC50 increased markedly with increasing silicon fertilizer concentration, TQ of three tested turfgrasses increased most markedly under Si56 treatment. Silicon fertilizer can enhance drought resistance of tested turfgrasses.5. At un-silicon fertilizer treatment, SOD and CAT activity of three tested turfgrasses for FWC75 and FWC50 were much lower than that of three tested turfgrasses for FWC100, less irrigation water, lower SOD and CAT activity. Following different concentration silicon fertilizer were applied, SOD and CAT activity of three tested turfgrasses for FWC100 did not increase markedly with increasing silicon fertilizer concentration, while SOD and CAT activity of three tested turfgrasses for FWC75 and FWC50 increased obviously with increasing silicon fertilizer concentration, whatever, silicon fertilizer could improve SOD and CAT activity of three tested turfgrasses under less irrigation water condition, especially, SOD and CAT activity of three tested turfgrasses increased markedly under Si56 treatment. Silicon fertilizer can enhance drought resistance of tested turfgrasses.6. At un-silicon fertilizer treatment, MDA content of three tested turfgrasses for FWC75 and FWC50 were much higher than that of three tested turfgrasses for FWC100, especially MDA content of three tested turfgrasses for FWC50 increased most obviously. Following different concentration silicon fertilizer were applied, MDA content of three tested turfgrasses for FWC100 did not increase obviously with increasing silicon fertilizer concentration, while MDA content of three tested turfgrasses for FWC75 and FWC50 decreased markedly with increasing silicon fertilizer concentration, especically MDA content of three tested turfgrasses declined markedly under Si56 treatment. Silicon fertilizer can enhance drought resistance of tested turfgrasses.7. At un-silicon fertilizer treatment, RDW and RACT of three tested turfgrasses for FWC75 and FWC50 were much lower than that of three tested turfgrasses for FWC100, less irrigation water, lower RDW and RACT of three tested turfgrasses. Following different concentration silicon fertilizer were applied, RDW and RACT of three tested turfgrasses for FWC100 did not change obviously with increasing silicon fertilizer concentration, and kept the same level, while RDW and RACT of three tested turfgrasses for FWC75 and FWC50 increased markedly with increasing silicon fertilizer concentration, especically RDW and RACT of three tested turfgrasses increased most markedly under Si56 treatment. Silicon fertilizer can enhance drought resistance of tested turfgrasses.8. RWC and TQ of tested Tall fescue declined obviously under drought stress following rewatering treatment, RWC and TQ of tested Tall fescue without application of silicon fertilizer was lower than that of tested Tall fescue with application of silicon fertilizer. Under drought stress, RWC and TQ of tested Tall fescue gradually declined with increasing silicon fertilizer concentration,RWC and TQ of tested Tall fescue with application of silicon fertilizer was higher than that of tested Tall fescue without application of silicon fertilizer,whatever, RWC and TQ of tested Tall fescue for FWC100 was lower than that for FWC75 and FWC50 at the same silicon fertilizer concentration. Drought exercise and silicon fertilizer can enhance drought resistance of tested Tall fescue.9. EL and LW of tested Tall fescue increased obviously under drought stress following rewatering treatment. At the end of drought stress (30 d), EL and LW of tested Tall fescue without application silicon fertilizer was much higher than that of tested Tall fescue with application silicon fertilizer; whatever, EL and LW of tested Tall fescue for FWC50 was lower than that of tested Tall fescue for FWC100 and FWC75 at the same silicon fertilizer concentration. Drought exercise and silicon fertilizer can enhance drought resistance of tested Tall fescue.10. SOD of tested Tall fescue increased momently and then decreased obviously, while CAT activity declined continuously under drought stress following rewatering treatment. At the end of drought stress (30 d), SOD and CAT activity of tested Tall fescue without application silicon fertilizer was much lower than that of tested Tall fescue with application silicon fertilizer; SOD and CAT activity of tested Tall fescue under drought stress were relative high with increasing silicon fertilizer concentration, whatever, SOD and CAT activity of tested Tall fescue for FWC50 were higher than that of tested Tall fescue for FWC100 and FWC75 at the same silicon fertilizer concentration. Drought exercise and silicon fertilizer can enhance drought resistance of tested Tall fescue.11. MDA content of tested Tall fescue increased obviously under drought stress following rewatering treatment. At the end of drought stress (30 d), MDA content of tested Tall fescue without application silicon fertilizer was much higher than that of tested Tall fescue with application silicon fertilizer; MDA content of tested Tall fescue declined differently with increasing silicon fertilizer concentration, whatever, MDA content of tested Tall fescue for FWC50 was lower than that of tested Tall fescue for FWC75 and FWC100, At the end of drought stress (30 d), MDA content of tested Tall fescue for Si56 was relative low. Drought exercise and silicon fertilizer can enhance drought resistance of tested Tall fescue.更多还原