| By the effects of salt stresses on the seed germinations of 10 pepper varieties,three petter breeds including high-salt tolerance breed d, mid-salt tolerance breed h, low- salt tolerance breed a were used as materials in the study. The changes of UWL and some relative physical characters during normal and salt resistance of petter seeding leaves was discussed, in order to offer theory thereunder for discuss salt enduring of petter and application of UWL on vegetable enduring breeding. The main results were as follows: 1. Low salt concentration had a stimulating effect on germination. As NaCl concentration rose, the inhibitive effects on the seed germinations obviously increased. The seed germinations of the ten pepper varieties were differently inhibited by the stress'Meiguochaodaniujiaojiao','Tedaniujiaojiao'and'Daniujiaojiao'were tolerant to salt,'Baojiaoniaiyanerhao'were not tolerant and the other were moderately tolerant.2. Under normal conditions, the UWL intensity of seeding leaves was increased with the rise of culture time.3. Under NaCl stress, UWL intensity of seeding leaves increased at beginning and decreased later. Under different NaCl concentration stress, the intensity of each seeding increased with the rise of NaCl concentration. When achieving at threshold value, UWL intensity of seeding began to weaken.The more increase of NaCl concentration, the more descending of UWL intensity.Different NaCl concentration breed had different changing range of UWL intensity. UWL intensity of high-Salt tolerance breed d was high and had low falling range, but low-Salt tolerance breed a have reverse trend, and mid- Salt tolerance breed h was between with the two others. There was a positive correlation between UWL intensity and Salt resistance of different breeds. The breeds fastness reflected by UWL was consistent with resulted by other physiological index. And the mensuration was easy, convenient, and delicacy.4. Under Salt stress, the chlorophyll content of all three peppter breed fell, so leaded the decline of catching and using light ability of leaves. And the photosynthetic rate and apparent quantum yield of carbon assimilation depressed with prolong of Salt stress and increase of NaCl concentration which had significant correlation with UWL. Relative to low-Salt tolerance breed, the Pn, AQY and light saturation point of high-Salt tolerance breed had slow downtrend, and remained high level. While low-Salt tolerance breed a fell greatly, and mid-Salt tolerance breed h was between with the two others. The results showed that there was a significant correlation between radiant intensity and photosynthesis of leaves.5. Under NaCl stress, the chlorophyll fluorescence parameter of different of pepper seeding leaves on resistance had different changes. On initial stages, Pn, Fv/Fm,φPSII and ETR decreased slowly.With the increase of threatening time, Pn, Fv/Fm,φPSII and ETR decreased greatly.6. The membrane permeability and contents of MDA increased in cultivars with the increase of NaCl concentration and prolonging of time. The activity of SOD and POD in the three cultivars showed at trend from increase to decrease inb shorter term, but it decreased in longer term under NaCl stress. With the prolong of threatening time, the metabolize enzymes were destroyed inside seeding body. And decompose rate of protein mended, and the protein content in every breed body began decreased, but the proline content increased slowly. During NaCl stress, the increasing rate of every physiological character of different of petter breed seeding leaves on resistance had different changes. Relative to low-salt tolerance breed, the proline content in high-salt petter seeding leaves increased quickly, and decompose rate of protein was slow, and remained high level. The production and cumulation of active oxygen and MDA of high-salt tolerance breed was slower than low-salt tolerance breed. There was some relativity between UWL with physiological metabolize of Pepper.
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