CAJ | 학술논문

目的黄瓜和番茄是我国主栽蔬菜种类，育苗过程中容易遭遇高温、高湿、弱光等不良环境，导致幼苗下胚轴徒长，严重影响后期丰产性。在控制幼苗徒长的实际操作中，利用植物生长调节剂、机械刺激、补光、温度调节、水分控制等调控方法容易受到多种因素影响而效果不佳。本文研究高浓度营养液对黄瓜和番茄幼苗下胚轴徒长的抑制作用，以期提出一种有效制御幼苗徒长的方法。方法试验以Hoagland标准营养液配方为基础浓度（设为1.0C），通过成比例增减大量元素组分用量而不改变微量元素组分用量，组成0.5C、2.5C、5.0C、7.5C、10.0C和12.5C 6个浓度。以0.5C为对照，在日光温室条件下分别对黄瓜和番茄幼苗进行灌施处理。待幼苗生长至子叶平展期时，测定黄瓜和番茄幼苗形态及生长指标，研究营养液浓度对幼苗下胚轴细胞长度、生长速率及内源激素含量的影响；随后对幼苗进行0.5C低浓度营养液的恢复生长处理，待幼苗生长至第一真叶平展期时，再次进行幼苗形态及生长指标的测定，从而确定高浓度营养液对黄瓜和番茄下胚轴徒长的抑制效果及机制，并确定最适合制御幼苗徒长的营养液浓度。结果6种浓度营养液对黄瓜和番茄幼苗下胚轴徒长的影响结果为：1）高浓度营养液显著提高了基质EC值（ r＝0.99），黄瓜和番茄幼苗在子叶平展期其下胚轴生长受到明显抑制，下胚轴长度、绝对生长速率和含水量均呈下降趋势，下胚轴皮层薄壁细胞轴／径向生长也受到影响。与对照相比，10.0 C营养液处理下黄瓜和番茄幼苗下胚轴皮层薄壁细胞缩短为49％和48％。2）随着营养液浓度的增加，黄瓜和番茄下胚轴内源激素含量发生显著变化，其中赤霉酸（GA3）、玉米素核苷（ZR）含量呈降低趋势，而脱落酸（ABA）含量呈升高趋势，且ABA含量与下胚轴长度呈极显著负相关关系（P＜0.01）。生长素（IAA）含量在不同浓度营养液处理下呈现区位性变化特征。3）在幼苗子叶平展期重新灌施0.5C浓度的营养液，对5.0C和7.5C处理下生长的幼苗均有恢复生长的作用，且幼苗株高／茎粗比明显优于对照和其它处理，该浓度可望有效避免幼苗徒长。结论高浓度营养液通过改变幼苗内源激素的动态平衡，特别是促进ABA的合成和积累，从而抑制幼苗下胚轴皮层细胞伸长生长，有效制御幼苗徒长。灌施高浓度营养液对黄瓜、番茄幼苗下胚轴伸长的抑制作用可以通过降低营养液浓度而得到解除，这种防治幼苗徒长的操作方法简便易行，具有潜在的应用前景，但在不同品种蔬菜幼苗生长过程中，最优化的营养液施用浓度及其影响机制尚需进一步研究分析。目的黃瓜和番茄是我國主栽蔬菜種類，育苗過程中容易遭遇高溫、高濕、弱光等不良環境，導緻幼苗下胚軸徒長，嚴重影響後期豐產性。在控製幼苗徒長的實際操作中，利用植物生長調節劑、機械刺激、補光、溫度調節、水分控製等調控方法容易受到多種因素影響而效果不佳。本文研究高濃度營養液對黃瓜和番茄幼苗下胚軸徒長的抑製作用，以期提齣一種有效製禦幼苗徒長的方法。方法試驗以Hoagland標準營養液配方為基礎濃度（設為1.0C），通過成比例增減大量元素組分用量而不改變微量元素組分用量，組成0.5C、2.5C、5.0C、7.5C、10.0C和12.5C 6箇濃度。以0.5C為對照，在日光溫室條件下分彆對黃瓜和番茄幼苗進行灌施處理。待幼苗生長至子葉平展期時，測定黃瓜和番茄幼苗形態及生長指標，研究營養液濃度對幼苗下胚軸細胞長度、生長速率及內源激素含量的影響；隨後對幼苗進行0.5C低濃度營養液的恢複生長處理，待幼苗生長至第一真葉平展期時，再次進行幼苗形態及生長指標的測定，從而確定高濃度營養液對黃瓜和番茄下胚軸徒長的抑製效果及機製，併確定最適閤製禦幼苗徒長的營養液濃度。結果6種濃度營養液對黃瓜和番茄幼苗下胚軸徒長的影響結果為：1）高濃度營養液顯著提高瞭基質EC值（ r＝0.99），黃瓜和番茄幼苗在子葉平展期其下胚軸生長受到明顯抑製，下胚軸長度、絕對生長速率和含水量均呈下降趨勢，下胚軸皮層薄壁細胞軸／徑嚮生長也受到影響。與對照相比，10.0 C營養液處理下黃瓜和番茄幼苗下胚軸皮層薄壁細胞縮短為49％和48％。2）隨著營養液濃度的增加，黃瓜和番茄下胚軸內源激素含量髮生顯著變化，其中赤黴痠（GA3）、玉米素覈苷（ZR）含量呈降低趨勢，而脫落痠（ABA）含量呈升高趨勢，且ABA含量與下胚軸長度呈極顯著負相關關繫（P＜0.01）。生長素（IAA）含量在不同濃度營養液處理下呈現區位性變化特徵。3）在幼苗子葉平展期重新灌施0.5C濃度的營養液，對5.0C和7.5C處理下生長的幼苗均有恢複生長的作用，且幼苗株高／莖粗比明顯優于對照和其它處理，該濃度可望有效避免幼苗徒長。結論高濃度營養液通過改變幼苗內源激素的動態平衡，特彆是促進ABA的閤成和積纍，從而抑製幼苗下胚軸皮層細胞伸長生長，有效製禦幼苗徒長。灌施高濃度營養液對黃瓜、番茄幼苗下胚軸伸長的抑製作用可以通過降低營養液濃度而得到解除，這種防治幼苗徒長的操作方法簡便易行，具有潛在的應用前景，但在不同品種蔬菜幼苗生長過程中，最優化的營養液施用濃度及其影響機製尚需進一步研究分析。
목적황과화번가시아국주재소채충류，육묘과정중용역조우고온、고습、약광등불량배경，도치유묘하배축도장，엄중영향후기봉산성。재공제유묘도장적실제조작중，이용식물생장조절제、궤계자격、보광、온도조절、수분공제등조공방법용역수도다충인소영향이효과불가。본문연구고농도영양액대황과화번가유묘하배축도장적억제작용，이기제출일충유효제어유묘도장적방법。방법시험이Hoagland표준영양액배방위기출농도（설위1.0C），통과성비례증감대량원소조분용량이불개변미량원소조분용량，조성0.5C、2.5C、5.0C、7.5C、10.0C화12.5C 6개농도。이0.5C위대조，재일광온실조건하분별대황과화번가유묘진행관시처리。대유묘생장지자협평전기시，측정황과화번가유묘형태급생장지표，연구영양액농도대유묘하배축세포장도、생장속솔급내원격소함량적영향；수후대유묘진행0.5C저농도영양액적회복생장처리，대유묘생장지제일진협평전기시，재차진행유묘형태급생장지표적측정，종이학정고농도영양액대황과화번가하배축도장적억제효과급궤제，병학정최괄합제어유묘도장적영양액농도。결과6충농도영양액대황과화번가유묘하배축도장적영향결과위：1）고농도영양액현저제고료기질EC치（ r＝0.99），황과화번가유묘재자협평전기기하배축생장수도명현억제，하배축장도、절대생장속솔화함수량균정하강추세，하배축피층박벽세포축／경향생장야수도영향。여대조상비，10.0 C영양액처리하황과화번가유묘하배축피층박벽세포축단위49％화48％。2）수착영양액농도적증가，황과화번가하배축내원격소함량발생현저변화，기중적매산（GA3）、옥미소핵감（ZR）함량정강저추세，이탈락산（ABA）함량정승고추세，차ABA함량여하배축장도정겁현저부상관관계（P＜0.01）。생장소（IAA）함량재불동농도영양액처리하정현구위성변화특정。3）재유묘자협평전기중신관시0.5C농도적영양액，대5.0C화7.5C처리하생장적유묘균유회복생장적작용，차유묘주고／경조비명현우우대조화기타처리，해농도가망유효피면유묘도장。결론고농도영양액통과개변유묘내원격소적동태평형，특별시촉진ABA적합성화적루，종이억제유묘하배축피층세포신장생장，유효제어유묘도장。관시고농도영양액대황과、번가유묘하배축신장적억제작용가이통과강저영양액농도이득도해제，저충방치유묘도장적조작방법간편역행，구유잠재적응용전경，단재불동품충소채유묘생장과정중，최우화적영양액시용농도급기영향궤제상수진일보연구분석。
Objectives]Cucumber (Cucumis sativus) and tomato (Lycopersicon esculentum) are main cultivated vegetable species in China. The seedling growth in breeding processes is vulnerable to disadvantageous environments, such as high temperature, high humidity and weak light, which lead to excessive hypocotyl stretch and reduce yield at later stage.Several methods such as plant growth regulators, mechanical stimulations, supplement of light, temperature modulation and water limitation are used to prevent excessive hypocotyl stretch, but the effects are always not satisfied due to complicated influence factors.To develop an effective method for controlling hypocotyl stretch in cucumber and tomato seedlings, this paper focused on the inhibition effect of high strength nutrient solution on hypocotyl stretch in cucumber and tomato seedlings.[Methods] A concentration of complete macroelement of 1.0 strength Hoagland nutrient solution was defined as fundamental formula ( 1.0 C ) . Other nutrient solution concentration gradients involved in this experiment were 0.5, 2.5, 5.0, 7.5, 10.0 and 12.5C by adding macroelement compositions proportionally without changing the microelements compositions.The 0.5C nutrient solution was set as the control group, and others were the treatment groups.After watering cucumber and tomato seedlings by different nutrient solutions in greenhouse conditions, the growth parameters were measured, and the nutrient solution effects on hypocotyl cortical cell length, growth rate and phytohrmone levels were determined at the cytoledon extending stage.Then seedlings were rewatered by the 0.5C nutrient solution to restore the inhibition growth of hypocotyl stretch.The growth parameters were measured at the first true leaves extending stage.The effects and mechanism of high nutrient solution on inhibiting hypocotyl stretch were determined, and the optimal strength was acquired by appropriate effect on cucumber and tomato seedlings.[Results]The effects of six strength ( 0.5, 2.5, 5.0, 7.5, 10.0 and 12.5C ) Hoagland ’ s nutrient solution on controlling the excessive hypocotyl stretch are:1) The electrical conductivity (EC) of substrate increases linearly (r=0.99) and growth of both cucumber and tomato are inhibited gradually from 0.5C to 12.5C nutrient solution.Compared with the 0.5C nutrient solution, the lengths of hypocotyl cortical cell are decreased by 49% in cucumber and 48% in tomato under the 10.0C nutrient solution.2) The endogenous phytohormone homeostasis is disturbed by decreasing GA3 and ZR levels but increasing ABA level which significantly displays a negative correlation with hypocotyl length ( P<0.01 ) .The IAA level shows different tendency dependent on the concentration of nutrient solution.3 ) The growth of hypocotyl stretch that has been inhibited by high strength of nutrient solution could be restored to different degrees by rewatering 0.5C nutrient solution.Especially in the 5.0C and 7.5C treatments, the ratios of plant height/stem diameter are better than those in other treatments, which could be expected to effectively control excessive hypocotyl stretch.[Conclusions] High strength nutrient solution contributes to the inhibition effect on excessive hypocotyl stretch by changing endogenesis phytohormone homeostasis, apparently because of promoting more ABA synthesis and accumulation in hypocotyl cells, and shortening hypocotyl cortical cell length.The inhibition effect could be restored by decreasing the nutrient solution concentration.The method exhibits potential application prospect due to simple maneuverability and obvious effects, but the optimal strength and mechanism on different vegetable species still should be further studied and analysed.