Abstract: An observation was made on the seed germination and seedling growth of 36 oat (Avena fatua L.) varieties under NaClNa₂SO₄ stress in Petri dish, aimed to provide theoretical reference for selecting salttolerant oat varieties, cultivating oat on salinealkali soil, and breeding salttolerant species. Salt stress inhibited the seed germination and seedling growth. Low salt concentration (0.4%) favored the growth of test oat cultivars, and promoted the germination and seedling growth of salttolerant varieties. Salt concentration 1.2% was the appropriate salt concentration for the identification of oat salttolerance. The test 36 oat varieties had greater differences in their salttolerance, and could be divided into three types, i.e., tolerant, moderate tolerant,and nontolerant. Different oat varieties and types at their seed germination stage had different salttolerant concentration range, and the salttolerant indices had definite differences in reflecting the salttolerance of oat, among which, germination rate, germination index, simple vigor index, and individual dry mass were more available.

Key words: Changbai Mountains, Betula ermanii, Ecotone, Position