The Response Of Seed Germination And Seedlings Growth Of Xanthoceras Sorbifolium Bunger To Salinity-alkalinity Stress

Xanthoceras sorbifolium bunge is a unique woody oil plant in China,and it is also an excellent soil and water conservation tree species.The distribution range is wide and the ecological benefits are good.The response of the seeds and seedlings to the salt and alkali stress is determined,It can provide guidance for the selection of the site of Xanthoceras sorbifolium bunge and the expansion of planting range.In this paper,salt and alkali stress of Xanthoceras sorbifolium bunge were studied by setting different concentrations of gradient saline solution,and the changes of seeds and seedlings were analyzed.The results show:(1)Mixed salt and alkali stress The water absorption process before the seedling of Pinellia ternata can be divided into three periods:accelerated absorption period,stable water absorption period and saturated water absorption period.(0-6 hours)to accelerate the water absorption period,(16-36)for the stable water absorption period,(40-120 hours)for the saturated water absorption period.In the case of accelerated water uptake and salt concentration,the water absorption of Xanthoceras sorbifolium bunge was gradually accelerated with the increase of alkali concentration.In the case of stable water uptake and salinity,The water uptake rate of seed reached the maximum and then decreased,and the water absorption reached the maximum under the light alkali stress.Under the condition of saturated water absorption and salinity,the water absorption of Xanthoceras sorbifolium bunge The water loss of seeds was the fastest,and the water absorption rate was the fastest.(2)The low concentration(0.1%?0.3%)of neutral salt promoted the germination of Xanthoceras sorbifolium bunge under the same pH condition.The medium and high concentration(0.5%?1%)Of the neutral salt on the yield of Xanthoceras sorbifolium has inhibited,in particular,1%inhibition of salinity serious.With the increase of pH,the germination rate of the seeds showed obvious difference,the effect of light base salt stress on seed germination rate was not obvious,the germination rate of seed was the lowest under heavy alkali salt treatment,and the effect of heavy alkali salt stress on seed germination Significantly higher than single salt stress.(3)Under the saline-alkali stress,the malondialdehyde,proline and soluble sugar of the leaves of Xanthoceras sorbifolium bunge were positively correlated with the salt concentration and pH value.Under salt stress,malondialdehyde,proline,Soluble sugar compared with the control is not obvious,indicating that the fruit has a certain salt tolerance.However,when the alkalinity of a certain degree of salinity reached 1%,malondialdehyde,proline,soluble sugar increased sharply,indicating that 1%salt concentration will cause greater damage to the genus Xanthoceras sorbifolium bunge seedlings.When the pH was above 9.51,the chlorophyll,plant height and ground diameter of the leaves of Xanthoceras sorbifolium bunge were significantly decreased with the increase of salinity concentration.Description PH9.51 or more,Xanthoceras spp.Seedlings were injured.(4)Salt concentration increased to 1%,PH reached 9.51,Xanthoceras sorbifolium bunge growth physiology were seriously inhibited,plant physiological protection early warning mechanism reaction is strong,indicating that the genus Xionggan fruit seedlings have the strongest physical damage,can also indirectly explain the text Correlative salt tolerance threshold of 1%,alkali resistance threshold of 9.51.