Assessment of Salt Resistance and Physiology Basis of Seed and Seedling of Ceratoides
YI Jin 1,WANG Xue min 1,GU An lin 2,XU Jun 1 (1. Inner Mongolia Agricultural University, Huhhot 010019 China; 2. Grassland Research Institute; Chinese Academy of Agricultural Sciences, Huhhot, Inner Mongolia Autonomous Region 010010, China)
A study on the seven Ceratoides (Tourn.) Gagnebin seed samples for their germinating ability and seedling salt resistance shows that different seedling species and ecotypes bear with different degrees of salt concentration. C.arborescens boasts the strongest salt tolerance, C.arborescens of the keerqin ecotype comes second, while C.latens of the cold desert ecotype and C.ewersmanniana are the least salt tolerant. Ceratoides seed and seedling's salt tolerance is in proportion with the seed vigour. In general, seeds that are produced in adverse conditions exhibit lower vigour, and the seedlings lack salt tolerance. The seedlings' ability of enduring an environment of half lethal salt concentration is significantly related to the seed germinating rate, the germination index,and the seed vigour index (r=0.82 *,0.93 ** ,0.90 ** respectively).Study on the physiological basis of the seedling salt resistance shows that the seed nitrogen content is in direct proportion both with the seedling salt resistance capacity(r=0.88 *,0.90 ** ), and its phosphorus content (r=0.77,0.68),though not closely related to the seed carbohydrate content (r= -0.33～ 0.55). It is summarized that the seedling's tolerance of half lethal salt concentration, the seed vigour index ,and the seed nitrogen content could be regarded as the physiological index for assessing the level of the seed salt tolerance and whether it be selected for breeding.