| Beet is one of the main sources of sugar crops.China beet mainly distributed in north latitude 40°north,including the northeast,north,northwest three producing areas.Xinjiang,Heilongjiang,Inner Mongolia is the country’s top three sugar beet areas,beet planting area accounted for more than 90%of the national sugar beet area,the total output of nearly 90%of the national beets.At the same time,"three North" region is also the main distribution of saline soil in China,saline soil cultivation of sugar beet has been a hundred years of history.It is important to study the effects of different salinization degree on the growth and development of sugar beet and the quality of sugar accumulation.In this paper,15 kinds of salt-tolerant sugar beet germplasm resources were used as the research object to carry out large-scale pot experiment,and the effects of different saline-alkali gradient treatments on the emergence rate,dry fresh weight,chlorophyll and superoxide dismutase（SOD）,Malondialdehyde（MDA）content and leaf membrane permeability were studied.Research indicates:1.The effect of different salinity treatments on the germination rate and emergence rate of sugar beet seeds was different.With the increase of salinity,the seedling emergence time was also changed（4-15d）.（SOD,MDA,conductivity）and chlorophyll and dry fresh were selected for the salt tolerance（salinity content）of different beet varieties,and the comparison between the two groups was carried out.It can be seen that’H003’ has strong salt tolerance and high seedling rate,and can be used as the main cultivar of pot experiment in this paper.2.The activity of superoxide dismutase（SOD）in the leaves of sugar beet increased first and then decreased,and the decrease of the stress time increased with the increase of the degree of salt and alkali stress.The results showed that the ability of nitrogen assimilation under salt and alkali stress was low,the accumulation of organic matter was also reduced,and the growth and development ability of sugar beet decreased.3.The content of malondialdehyde（MDA）and the membrane permeability of the leaves increased with the increase of the degree of salt and alkali stress,and the content of malondialdehyde（MDA）and the membrane permeability were lower,Indicating that the salt damage suffered by the relatively large,so that the accumulation of organic matter in the beet seedlings was peroxidation,the cumulative accumulation of organic matter was significantly reduced.4.The results showed that the growth of sugar beet seedlings was always in the salt stress during the whole process of potted plants,but the degree of salinization in potted soil decreased with the decrease of pH value,which indicated that the growth of sugar beet seedlings was The effect of NaCl and NaHCO3 was the most significant. |
