【作者】 丁烽；

【导师】 王宝山；

【作者基本信息】 山东师范大学 ， 植物学， 2007， 硕士

【摘要】 泌盐盐生植物最显著的形态结构特征是具有泌盐结构,可将体内过多的盐分排出体外,这种结构包括盐腺和盐囊泡两类。它们在调节体内离子平衡,维持渗透压稳定,提高植物的耐盐性等方面发挥重要作用。现在已经清楚叶片上总的盐腺的泌盐速率随着外界盐浓度的升高而增加,分泌物的成分取决于根系的环境组成。盐腺密度随着外界盐浓度的升高而增加而且喷洒BA能显著使盐腺的密度增加。然而有三个重要的问题至今尚不清楚:(1)不同盐浓度下泌盐速率的变化是由于单个盐腺泌盐效率的变化还是由于盐腺数目的变化引起的?(2)单个盐腺对不同的离子分泌是否具有选择性?(3)盐腺的泌盐速率和盐腺发育之间有无联系?本实验以中华补血草(Limonium sinense Kuntze)为实验材料,研究了不同浓度的NaCl和KCl处理对其生长、盐腺发育和泌盐速率的影响。其主要结果如下:1 NaCl和KCl处理对中华补血草生长的影响随着NaCl浓度的升高,植株干重和鲜重均显著升高,100 mmol/L NaCl处理时植株干鲜重达到最大,尔后干、鲜重都逐渐下降;随KCl浓度的升高中华补血草干、鲜重增加,50 mmol/L KCl处理达到最大值,尔后干、鲜重都逐渐下降。2 NaCl和KCl处理对中华补血草叶片盐腺发育的影响与对照相比,300 mmol/L NaCl处理下盐腺的分泌细胞及平均直径差别不显著,100、200 mmol/L NaCl处理下显著增大;与对照相比,100 mmol/L KCl处理下,盐腺直径显著增大,200、300 mmol/L KCl处理下盐腺直径显著减小。100 mmol/L NaCl处理下盐腺直径与100 mmol/L KCl处理下盐腺直径无显著性差异;200、300 mmol/L NaCl处理下盐腺直径均显著高于同等浓度KCl处理下盐腺的直径。随着NaCl浓度的升高,叶片上表面盐腺总数明显高于对照;随着KCl浓度的升高叶片上表面盐腺总数显著增多。3 NaCl和KCl处理对中华补血草盐腺泌盐速率的影响随NaCl和KCl浓度的升高,单个盐腺的泌盐速率和叶片整体泌盐速率均显著升高;当NaCl和KCl的浓度同为100 mmol/L和200 mmol/L时,叶片Na+的分泌速率显著高于K+;当NaCl和KCl的浓度同为200 mmol/L时,单个盐腺的Na+分泌速率高于K+, 100 mmol/L和300 mmol/L时单个盐腺的Na+与K+分泌速率无显著性差异。这些结果表明适当浓度的NaCl和KCl处理显著促进中华补血草盐腺的发育及泌盐能力,过高浓度的NaCl和KCl处理使盐腺的直径减小,却显著促进盐腺的泌盐能力。更多还原

【Abstract】 The most remarkable morphological characteristics of recretohalophytes are the salt-secreting structures (salt glands and salt bladders) that can excrete excessive salts. They play an important role in regulating ion balance, maintaining the stability of osmotic pressure and enhancing the salinity tolerance. It is clear that the gland secretion increases with external concentration of exposure to salinity and the composition of the secretions is highly dependent on the composition of the root environment. However, there are three particularly pertinent questions that have not been satisfactorily resolved: one is that the variation of salt secretion rate is due to the efficiency of the secretion process per salt gland or to changes in the number of salt glands at different salinity levels? The second is that there is any selectivity in different ions per salt glands? The last is what’s the relationship between the salt secretion rate and the development of salt glands? Limonium sinense seedlings were used to study the effects of NaCl and KCl on the growth, development and salt secretion rate of salt glands. The results were shown as follows:1 Effects of NaCl and KCl on growth of Limonium sinenseBoth the fresh and dry weight of the whole plant increased with increasing NaCl concentration. Both the fresh and dry weight of the whole plant reached the maximum under 100 mmol/L NaCl treatment and then declined with increasing NaCl concentration. Both the fresh and dry weight of the whole plant increased with increasing KCl concentration and reached the maximum under 50 mmol/L KCl treatment, and then declined with increasing KCl concentration.2 Effects of NaCl and KCl on development of salt glandsUnder 100 mmol/L and 200 mmol/L NaCl treatment, the average diameter of salt glands was significantly bigger than that of controls; No significant difference was observed between plants treated with 300 mmol/L NaCl and controls. Under 100 mmol/L KCl treatment, the average diameter of salt glands was significantly bigger than that of controls, while the average diameter of salt glands was significantly smaller than that of controls under 200 mmol/L and 300 mmol/L KCl treatments. There was no significant difference in the average diameter of salt glands between plants treated with 100 mmol/L NaCl and 100 mmol/L KCl. When the concentrations of NaCl and KCl were 200 mmol/L or 300 mmol/L, the diameters of salt glands under NaCl treatment were significantly bigger than those under KCl treatment. The total number of salt glands under NaCl and KCl treatments was significantly higher than that of controls.3 Effects of NaCl and KCl on salt secretion rate of salt glandsSalt secretion rate per salt gland and per leaf increased markedly with the increase of NaCl and KCl concentrations. When the concentrations of NaCl and KCl were 100 mmol/L or 200 mmol/L, Na+ secretion rate per leaf was significantly higher than K+ secretion rate. When the concentrations of NaCl and KCl were both 200 mmol/L, Na+ secretion rate per salt glands was significantly higher than K+ secretion rate. There was no significant difference between the Na+ secretion rate per salt glands and K+ secretion rate under 100 mmol/L and 300 mmol/L NaCl and KCl treatments.The results suggested that modest NaCl and KCl treatments significantly stimulated the development and salt secretion rate of salt glands of Limonium sinense, severe NaCl and KCl treatments inhibited the development of salt gland significantly, but still markedly enhanced salt secretion rate.更多还原