Studies On Salt Tolerance Biology Of Thellungiella Halophila

Flowering physiology, content change of ions, physiological and biochemical indexes and stress protein in different concentration of NaCl were studied. And the effect of NaCl and fluorescein sodium treatment on plants was analyzed. The main results were as follows:(1)Influence of temperature and salt treatment on flower formation in vitro was studied. The results showed that the ratio of seed germination treated by low temperature was higher than that of the contrast and the time of seed germination was short. So, low temperature treatment accelerated seed germination and bud of Thellungiella halophila. Low salt concentration had little influence on seed germination and plant bloom.While high salt concentration restrained seed germination and plant bloom.(2) Effect of salt treatment on ion content of of Thellungiella halophila was studied. Determining the variation of ion content in the body of Thellungiella halophila by atomic absorption spectrometer, we found that content of Na⁺ increased, K⁺ content above the ground decreased continuously, the content of belowground decreased first and then increased and the trend of Ca²⁺ content was similar to that of K⁺, with the increase of NaCl concentration in the treatment of NaCl.The increase of Na⁺/K⁺ indicated that high concentration of Na⁺ restrained the absorption of K⁺.With the treatment of fluorescein sodium, Na⁺ content of underground part increased. Aboveground increased first, then decreased and finally increased again; in the treatment range K⁺ content both of the parts increased first and decreased then; Ca2⁺ content aboveground decreased and belowground increased. The ratio of Na⁺/K⁺ aboveground increased first, then decreased and finally increased again, while it increased all the time underground.(3) Influence of the treatment of NaCl and fluorescein sodium to the four physiologic indexes of Thellungiella halophila was studied.With the treatment of NaCl, activity of SOD and POD in underground part of Thellungiella halophila strengthened first and weakened then. While it weakened first, then strengthened and finally weakened in aboveground part. MDA content decreased first and then increased in both parts. Soluble protein content increased gradually with the increase of NaCl concentration.With the treatment of fluorescein sodium, activity of SOD and POD in the body of Thellungiella halophila strengthened first and weakened latter. MDA content increased first, then decreased and increased finally in the aboveground part; in the belowground part it decreased first, then increased, decreased again, and finally increased. Soluble protein content decreased first, increased then, decreased again and increased finally with the treatment of fluorescein sodium.(4)SDS-PAGE cataphoresis of adversive albumen of Thellungiella halophila under salt stress was studied.With the treatment of low concentration salt, the content of 68.2kD,61.6kD,54.9kD,44.9kD,34.4kD,28.3kD,27.0kD protein stripes increased evidently. With the increase of concentration and lengthening of time, many proteines were degradable. With the treatment of 1.0% concentration and 24-hour, the content of stripes of 61.6kD,27.0kD was larger than that of the contrast. However, with the increase of concentration and time, they started to decrease, which indicated that these two stripes had important effect on adverse resistance of Thellungiella halophila within this concentration and time.With low concentration and short time, the temporary protein stripes appeared in the body of Thellungiella halophila,and with the increase of concentration and time,many stripes disappeared or decreased. With the treatment of 2.0% concentration and 48-hour time, protein content of 70.2kD,59.7kD,27.8kD,23.9kD,22.5kD,21.9kD,20.7kD,14.8kD increased obviously, and they decreased with the extention of time.(5) We found that fluorescein sodium could be used as a kind of indicator for the transport pathway of nutrient substance in plants.Effects of NaCl and fluorescein sodium treatment on four physiological indexes of Thellungiella halophila. Determination results of (2) and (3) showed that, the change of physiological indexes and inner ions contents of Thellungiella halophila (especially the roor system) was some the same whether be treated with fluorescein sodium or NaCl. So we suggested that the fluorescein sodium can be used as a kind of indicator to reflect the action of Na⁺. According to the results of (2), (3) and (4), we believed that Thellungiella halophila should be belonged to a kind of salt-dilution-halophyte instead of a kind of salt-exclude- halophyte, which was same to its congenetic species Thellungiella salsuginea.