Seed germination of Chionanthus retusa and Cedrela sinensis under salinity stress.
Zhang Jianfeng; Li Jiyue; Xing Shangjun; Chi Jinbiao; Song Yumin. Shandong Academy of Forestry, Jinan, 250014, P. R.
China. Two tree species, \%Chionanthus retusa\% and \%Cedrela sinensis\% are important ones for forestation and garden greening. In order to test the salinity tolerance of their seeds, an experiment of seed germination under the conditions of two salts—NaCl and NaCl+KCl(1∶1 mol)—with five treatments 0, 0 2%, 0 4%, 0 6%, 1 0% was operated between March and May, 2000 in Shandong Provincial Academy of Forestry in eastern China. The results showed that the two kinds of salts both had harmful influences on seed germination as well as seedling growth. With the rising of salinity concentration, the germination rates decreased, and the seedlings' growing worsened. Nevertheless, the two species were tolerant to salinity to a certain extent. When salt content reached 0 4%, the germination rates all were over 80%. Additionally compared with compound salts (NaCl+KCl), single salt (NaCl) was stronger to hinder seed germination and seedling growth, which indicated that K + could alleviate the negative effect of Na +. To compare salinity tolerance of various plants under different salts, the concept of Index of Salinity Tolerance was put forward based on the experiment, which could reflect objectively salt tolerant capability of plants.