【作者】 郑桂珍；

【导师】 李广敏； 关军锋；

【作者基本信息】 河北师范大学 ， 植物学， 2002， 硕士

【摘要】 本试验以冬小麦（Triticum aestivum L.）4185为试材，研究了正常供水和20％PEG-6000（-0.49MPa）渗透胁迫下不同浓度游离Ca²⁺、EGTA、LaCl₂、Verapamil及CPZ、TFP对小麦幼芽、根的生长和POD活性的影响，及渗透胁迫下CaM水平的变化；并分析了25％PEG-6000（-0.73MPa）渗透胁迫下LaCl₃、CPZ、TFP、CaCl₂和EGTA对小麦幼苗含水量、膜透性及生长量的作用，同时测定了渗透胁迫下小麦幼苗钙、CaM含量的变化，结果如下： 1渗透胁迫下，10⁷-10⁴mol／L的Ca²⁺对小麦幼芽及根系的生长有利，10^?和10^?mol／L的Ca²⁺则抑制小麦幼芽、根系的生长，对于渗透胁迫下10mmol／L EGTA预处理的小麦，1mmol／L的CaCl₂能使其生长得到部分逆转，而5mmol／L和10mmol／L的CaCl₂则抑制其生长，这表明，只有适宜浓度的Ca²⁺才对小麦的生长有利，Ca²⁺浓度过高，反而会抑制生长，并且，渗透胁迫下小麦幼芽、幼根对外源Ca²的依赖性增强，体现了钙对小麦抗旱的增强作用。 2渗透胁迫下，EGTA（1、5、10mmol／L）、LaCl₃（0.5、1mmol／L）、Verapamil（250、500μ mol／L）处理均抑制了小麦幼芽和根系的生长，并有明显的浓度效应，浓度越大，抑制程度也越大。而正常供水时，1mmol／L的EGTA和250μ mol／L Verapamil对小麦幼芽的生长无影响或稍有促进作用，这些结果表明，渗透胁迫下，小麦对缺钙更敏感，减少细胞外Ca²⁺或阻断Ca（2+）吸收，会抑制小麦的生长，说明钙对小麦抵御干旱的重要性。 3渗透胁迫下，CPZ（25、50、100、200μ mol／L）及TFP（10、25、50、100、200μ mol／L）处理小麦幼芽，抑制了小麦根系和幼芽的生长，并表现出明显的浓度效应，浓度越大，抑制程度越高；而正常供水时，25μ mol／L的CPZ和10μ mol／L的TFP对小麦幼芽和根系的生长无影响或有促进作用，这表明，渗透胁迫下，抑制CaM活性对小麦的生长不利，降低了小麦的抗旱性。 4渗透胁迫下，与对照相比，小麦幼芽的CaM含量在胁迫6h时降低，然后逐渐升高，并且CaM的高峰时间与芽生长的高峰期一致，而根系的CaM含 量在最刊的 24 h一百低丁对照，36h后增加到高了对照的水平c这些结果 表明，渗透胁迫初期抑制小支幼芽和根系的hM台成，可能是于旱胁迫反 应的信号之一，冈而，保持正常的Ca＼1功能对维持植株的抗旱性是至犬重 要的。 5渗透胁迫卜，外源游离＊一、“八、hCI、＼，；丑p。。门、nZ、仆P处理 促进了小麦幼芽和根系POD活性，并且经相关分析POD活性与小麦的生K 量丫显著或极显著负相关，冈此，内源Ca’－Ca＼l信使系纹可能通过调V POD 话性而影叼了小支幼芽的抗旱性。 6 不同叮G－6000渗透胁迫表明，10‘。的PEG－6000即抑制了小支根羊叶的钙 含量，且叮巳浓度增加，对钙吸收的抑制柑度也增加；x‘；旺G－即（）O处理， 小支幼白钙含量与对照相比在12卜时吐这川夭，在24h－ISh义逐渐升高， 】h时急剧减少，并且根系m氏的柠度最人，＃从之，叶片的变化最小。 7 渗透胁迫与对照相比，小支根系和叫片的〔J含量丫不同的变化趋势， 叶片的CaM在胁迫IZh时迅这升高，然后陆低，而根系的CaM则是在胁迫 12h irk少，然后逐渐增加，到 72h时义降到低丁对照的水平。说明(参透胁 迫卜，小主根系、口十片的Ca＼l有各白的灯异性啊应c最刊叶片Ca＼1升高利 根系 C a＼1降低，可能是幼由干旱信号乙一。 8 i＆透胁迫－卜，lin。of．L的 LaCI．、100 u。of’L的 CPZ、100 u。of．L的 TFP。 10mmolL CaCI。和sin。。l’L gi EGTA使小麦幼苗叶片的相对含水量及根系的 绝对含水量有不同程度的降低，这一结果表明，〔。‘－Cd信使系统参与了 渗透胁卫卜小支幼苗水分平街的调节。 9 渗透W迫卜，1＊。。卜L的L。CI、1加卜。oIL的CR、1b。O1L hCI。和 5。。O IL的 EGTj＼处理增加了小支幼曲叶片和根系的细胞 B莫侵胜，使小支幼 苗受伤害的程度增加，这说明Ca‘－Ca＼1信使系纹参与了细胞膜功能调乃。 10 渗透胁迫卜，LaCI．、CPZ、ITP处理小主幼苗，降低了小主口｝片的干重， 说明，C。’－CJ系纹调节了渗透胁迫卜小支口f片的生K，进而影啊到干物 质积累。更多还原

【Abstract】 The effects of Ca2, EGTA, LaCh, Verapamil, CPZ and TFP on growth and POD activity and the changes of CaM level in buds and roots were studied with winter wheat (Triticum aestivuni L.) 4185 under osmotic stress of 20% PEG-6000, and the effects of LaCl3, CPZ, TFP, CaCl2 and EGTA on relative water content, relative permeability of plasma membrane and growth of seedlings during osmotic stress of 25% PEG-6000, and of osmotic stress on Ca and CaM contents with winter wheat 4185 seedlings were investigated. The results were as follows:1 Under osmotic stress, Ca2+(l 0-1 0-4mol/L) was benefit to the growth of wheat buds and roots, and Ca2 (10-102mol/L) inhibited the growth of wheat.CaCh (Immol/L) could reversed the inhibition effect of EGTA(10mmol/L) pretreatment. but CaCl2 (Smmol.’L, lOmmol/L) inhibited the growth of wheat. These data indicated that only proper Ca2 concentration was benefit to the wheat growth. In addition, the dependence of wheat on Ca was enhanced under osmotic stress, which showed that Ca2+ was very important to drought-resistance of wheat.2 Under osmotic stress, EGTA(1 , 5, lOmmol/L), LaCl3(0.5, Immol/L) and Verapamil(250, 500 u mol/L) treatment inhibited thegrowth of wheat buds and roots, but EGTA(lmmol/L) and Verapamil (250 u mol/L) had no inhibition effect on the control buds growth. The results showed that under osmotic stress, the wheat was more sensitive to deficiency of Ca2+, when extracellular Ca2+ concentration was decreased or Ca2+ transportation blocked, the growth of wheat buds and roots would be inhibited. It indicated that Ca2+ played an important role in the drought-resistance of wheat.3 Under osmotic stress, CPZ (25, 50, 100, 200 u mol/L) and TFP (10, 25, 50, 100, 200 u mol/L) inhibited the growth of wheat budsand roots, and the inhibition effect was increased with the increase of the treatment concentration, but CPZ (25 u mol/L) and TFP ( 10 U mol/L) had no inhibition effect on the control wheat. These data showed that it was disadvantage to the wheat growth when the activity of CaM was inhibited under osmotic stress, thus declined the capability of drought-resistance of wheat.4 Compared with the normal water supply, the CaM content of decreased at first 6 h, then increased slowly in wheat buds treated with 20% PEG-6000. When the CaM content was the most, the growth rate of wheat buds was the fastest. However, the CaM content of roots was lower than the control during the first 24 h. then it increased and surpassed the control. The data indicated that the CaM content decreased at the beginning of the osmotic stress might be one of the signals of drought reaction. Thus maintaining the normal CaM function was very important to sustain drought-resistance of wheat.5 Under osmotic stress, exogenous Ca +, EGTA, LaC, Verapamil, CPZ and TFP enhanced the POD activities of wheat buds and roots, and the POD activity negatively correlated with the fresh weight of wheat. So that Ca2+-CaM message system might affect thedrought-resistance of wheat by regulating the POD activity.6 After treated the wheat seedlings with different concentration PEG-6000, the results showed that 10% PEG-6000 decreased the calcium content of wheat roots, stems and leaves. The inhibited effect of Ca + absorption was enhanced with increase of the PEG treatment concentration. The calcium content of seedlings declined at 12h compared with the control, then increased from 24h to 48h,at last decreased quickly at 72h after treated with 25% PEG-6000. The decline of calcium amount of roots \vas the biggest, then stems, the leaves least.7 Compared with the control, the CaM content changes of wheat leaves and roots were different under osmotic stress. CaM content of leaves increased quickly at 12h,then decreased, however, CaM content of roots decreased at 12h,then increased during 24h to 48h,and declined again at 72更多还原