Effects of pericarp removal and different germination conditions on seed germination and saline-alkali tolerance of Amorpha fruticosa

In this paper, neutral salt NaCl and basic salt Na2CO3 were used to simulate salt stress and alkali stress respectively, and the effects of salt stress and alkali stress on seed germination and growth changes in natural saline-alkali soil were studied, in order to provide theoretical basis for making full use of plant resources and improving production efficiency. The fruit peel of Amorpha fruticosa contains a lot of lipids, which has a significant effect on seed germination. Under salt stress, removal of pericarp significantly increased germination rate, germination potential and germination index (P< 0.05), and significantly shortened germination time of seeds (p< 0.05), which accelerated the establishment of seedlings, reduced the stress time during germination, and advanced the transition from heterotrophic to autotrophic, accumulating more anions and organic solutes to adapt to salt stress. Therefore, when planting in neutral salt soil, it can be used to remove the peel for sowing to improve the planting effect. However, under alkali stress, the growth is inhibited by the absorption of a large amount of Na+ and high pH value, so it is not suitable for removing the peel for sowing. Different germination conditions had significant effects on seed germination. The length and biomass of radicle and germ in sand culture were significantly higher than those in paper culture (P< 0.05). Under the condition of sand culture, the concentration of the treatment solution can be well maintained, which is conducive to fixing the seedlings and reducing the interference of other mineral elements. Therefore, sand culture method is recommended for seed germination experiments under stress, especially for plants with developed roots.