Study On Salt Tolerance Of 10 Germplasm Materials Of Leguminous Forage

Leguminous forage species have an important position in cropping structure adjustment because their function of improving and enriching soil.With the increasing of area of grassland soil salinization, requirements of leguminous forage planted in saline land increased day by day. So, it is particularly important for identification and screening salt-tolerance germplasm materials of leguminous forage .In this paper, salt-tolerance of seeds was evaluated at seed germination and seedling stage in simulating salt environment taking Astragalus adusrgens, Caragana intermedia, Vicia villosa, Onobrychis viciaefolia, Melilotus officinalis and five Melilotoides ruthenicas as materials, then salt-tolerance was identified in saline land . Eventually, the salt-tolerance of 10 germplasm materials were evaluated synthetically . The results showed: Vicia villosa > 3-1 Melilotoides ruthenica > Melilotus officinalis > 1-16 Melilotoides ruthenica,2-24 Melilotoides ruthenica > Astragalus adusrgens > Onobrychis viciaefolia > 3-4 Melilotoides ruthenica > 1-24 Melilotoides ruthenica > Caragana intermedia ,of which 3-1 Melilotoides ruthenica had stronger salt-tolerance among five Melilotoides ruthenicas .So it can be used as a good germplasm material for breeding new strain of Melilotoides ruthenica which had stronger salt-tolerance.The salt-tolerance of tested materials were different in different stage. At germination stage , the salt-tolerence of Vicia villosa was strongest; the salt-tolerence of Onobrychis viciaefolia, 1-24 Melilotoides ruthenica and 1-16 Melilotoides ruthenica were weakest. At seedling stage , the salt-tolerence of Astragalus adusrgens, Melilotus officinalis, Caragana intermedia and 3-4 Melilotoides ruthenica were strongest; the salt-tolerence of 1-24 Melilotoides ruthenica and 1-16 Melilotoides ruthenica were weakest.The salt-tolerence of tested materials were different in different saline soil. In Ba Meng heavy saline soil, the salt-tolerence of Vicia villosa,Melilotus officinalis,2-24 Melilotoides ruthenica,1-16 Melilotoides ruthenica, Onobrychis viciaefolia and 3-1 Melilotoides ruthenica were strong, the salt-tolerence of Caragana intermedia, 1-24 Melilotoides ruthenica and 3-4 Melilotoides ruthenica were weak. In Hai Liutu alkali soil, the alkali-resistance of Vicia villosa, Melilotus officinalis, 3-4 Melilotoides ruthenica and 3-1 Melilotoides ruthenica were strong, Caragana intermedia and 1-24 Melilotoides ruthenica's were weak. In Tianjin weight reading saline soil, the salt-tolerence of Vicia villosa, Melilotus officinalis, 1-16 Melilotoides ruthenica and 3-1 Melilotoides ruthenica were strong, Caragana intermedia and 1-24 Melilotoides ruthenica's were weak. Among them, salt-tolerence and alkali-resistance of Vicia villosa were all stronger than others.Vigor index could be used as a suitable index for identificating salt-tolerance of leguminous forage in seed germination, gemination index was took second place according correlation studies on every index at seed germination and seedling stage and emergence rate in saline soil. MDA content was considered as a suitable index for evaluating salt-tolerance of leguminous forage at seed germination and seedling stage, proline content was took second place.