Abstract:

The potted experiment were carried out to study the effect of different water stresses on physiological characteristics in root of different oat cultivars ‘Bayou3’ and ‘Mengyan1’, which different in drought resistance, at jointing stage and heading stage, and also to seek the response of water stress on physiological characteristics of different oat cultivars. The results showed that, at jointing stage, protein synthesis of drought resistance cultivar Mengyan1 in root was blocked at severe stress, but weak resistance cultivar ‘Bayou3’ was blocked at moderate stress; at heading stage, as water stress intensified, the protein content of weak resistance ‘Bayou3’ decreased more than that of ‘Mengyan1’; as water stress intensified, MDA content, protective enzyme activity (POD, SOD), REC and soluble sugar increased at two stages, and weak resistance cultivar ‘Bayou3’ increased more; under severe stress, MDA content of ‘Mengyan1’ increased 39.79%, 14.88%, but that of ‘Bayou3’ increased 188% and 45.98% respectively at jointing stage and heading stage. The SOD activity of ‘Mengyan1’ just increased 27.4%, but that of ‘Bayou3’ increased 98% under severe stress at jointing stage; the SOD activity in root decreased significantly at moderate water stress, which was 33.16%, but that of ‘Mengyan1’ still kept high level only decreased 4.05% at heading stage. In short, under moderate water stress, drought resistance cultivar ‘Mengyan1’ on root physiological characteristics affected less, had better drought resistance physiological characteristics at jointing stage.