Effects Of Endogenous Jasmine And Mycorrhizal Formation On Nacl Stress In Tomato

Saline soils seriously affect agricultural production. As the largest symbiosis between plants andsoil microbes, arbuscular mycorrhizal (AM) has been extensively studied on its regulatory role inplant (crop) response to salt stress. Recent years, increasing evidence has demonstrated thatjasmonic acid (JA) plays a crucial role in the symbiosis between plants and AM fungi. However,the action mechanism of JA is less understood. In this study, we used endogenous JA deficientmutant spr2and its wild type (wt) to comparatively investigate the role of JA in the formation ofAM between tomato plants and Glomus mosseae, as well as in tomato plant response to NaClstress. Results showed that the efficiency of AM formation in wt plants was higher than that inspr2plants. NaCl stress decreased the dry mass accumulation in the tested plants in adose-dependent manner, especially in spr2plants. However, the mycorrhizal plants exhibited anenhanced tolerance to NaCl stress relative to the non-mycorrhizal plants. NaCl stress increasedSOD and POD activities in wt and spr2plants as indicated by spectrophotometer measured andpolyacrylamide gel electrophoresis (PAGE), wherein the mycorrhizal plants performed greateractivities of SOD and POD than the non-mycorrhizal plants. Under the same dose of NaCl stress,wt plants had higher levels of SOD and POD than the spr2plants regardless of inoculation withGlomus mosseae. NaCl stress elevated CAT activity in all the tested plants, but the extent waslower than the SOD and POD. NaCl stress increased lipid peroxidation in wt and spr2plants asindicated by malondialdehyde (MDA) regardless of inoculation with Glomus mosseae in adose-dependent pattern. However, the mycorrhizal plants exhibited a reduced MDA levels thanthe non-mycorrhizal plants. In normal conditions, the chlorophyll content was lower in spr2plants than in wt plants, and AM increased the chlorophyll contents. NaCl stress significantlyenhanced proline levels with a dose-effective relationship, especially in the spr2plants. Based onthese data, it was concluded that JA played an important role in AM formation between tomatoplants and Glomus mosseae, and in tomato response to NaCl stress.