Effects Of NO On The Seed Germination And Seedling Growth Of Suaeda Salsa And Chenopodium Glaucum Under Saline-alkali Stress

Soil salinization is a serious problem facing the world.It is very important to improve and make full use of saline-alkaline land.Introducing and domesticating salt-tolerant plants in saline-alkali land are effective measures to improve and utilize saline-alkali land.Suaeda salsa and Chenopodium glaucum are true halophytes of Chenopodiaceae,and they are forages with salt and alkali tolerance.In order to fully explore the resource advantages of Suaeda salsa and Chenopodium glaucum,this study used Suaeda salsa and Chenopodium glaucum as experimental materials,and by artificially simulating the salt-alkali stress environment,the effects of neutral salt（Na Cl）and alkaline salt（Na HCO₃and Na₂CO₃）stress on seed germination and seedling growth were studied.On this basis,exogenous NO is applied to fully understand the role of NO in the salt-alkali stress tolerance of Suaeda salsa and Chenopodium glaucum.The influence of feed quality provides a theoretical basis for the subsequent use of these two plants for saline soil improvement and livestock feed.The main results are as follows:1.Saline-alkali stress reduced the seed germination rate,germination vigor,germination index,radicle length and sprout length of Suaeda salsa and Chenopodium glaucum.The germination rate,germination potential,and germination index of the alkaline salt treatment group were lower than those of the neutral salt treatment group,and the three parameters of Chenopodium glaucum were lower than those of Suaeda salsa.Exogenous application of NO alleviated the inhibitory effect of saline-alkali stress on seed germination.2.Saline-alkali stress inhibited the plant height,root length,fresh weight,leaf relative water content of Suaeda salsa and Chenopodium glaucum,and increased the relative conductivity value,MDA,H₂O₂,and superoxide anion content,which caused serious damage to plants.Saline-alkali stress increases the Na⁺content and Na⁺/K⁺ratio of the seedlings of Suaeda salsa and Chenopodium glaucum,and decreases photosynthesis.Suaeda salsa and Chenopodium glaucum have accumulated a large amount of proline by regulating SOD,POD and other enzyme activities.Soluble sugar to resist adversity.The relative conductivity value,MDA,H₂O₂,and superoxide anion content under alkaline salt treatment are all higher than those of neutral salt,indicating that the alkaline salt has a stronger inhibitory effect on the two plants,and the Chenopodium glaucum treatment group is higher than the Suaeda salsa treatment group,indicating that the Suaeda salsa is more tolerant to saline and alkali than Chenopodium glaucum.Exogenous application of NO alleviated the damage caused by saline-alkali stress to Suaeda salsa and Chenopodium glaucum,and played a role in regulating membrane damage,ion balance,oxidative damage,and photosynthesis.3.Saline-alkali stress reduced the crude protein,crude fat,and crude ash content of Suaeda salsa and Chenopodium glaucum to varying degrees,and increased the content of neutral detergent fiber,acid detergent fiber and crude fiber.The crude protein,crude fat,and crude ash content of the alkaline salt treatment group were lower than those of the neutral salt treatment group,indicating that the alkaline salt had a greater impact on the forage quality of the two forages.The content of crude protein,neutral detergent fiber and acid detergent fiber of Chenopodium glaucum is lower than that of Suaeda salsa.Exogenous application of NO increased the crude protein,crude fat,and crude ash content of the two plants under salt-alkali stress,and alleviated the inhibitory effect of salt-alkali stress on the feed quality of the two plants.