关键词: 马铃薯幼苗, 硒, 低温胁迫, 抗寒生理

Abstract:

Low temperature stress is a major obstacle to potato growth and development especially during
the early stage in winter fallowing fields in southern China．Taking potato variety‘Jinxiang’as test material，
this paper studied the effects of spraying Na₂SeO₃ with different selenium concentrations（1，3，5 mg·L^-1） and
different times（1，2，3）on cold resistance of potato seedlings respectively．The results showed that exogenous
spraying of 1，3，5 mg·L^-1 selenium solution could increase the chlorophyll contents of potato leaves，reduce
the relative conductivity，contents of MDA and hydrogen peroxide of leaves under low temperature stress．The
effect of spraying 3 mg·L^-1 was the best．The chlorophyll content of seedlings by spraying 3 mg·L^-1 selenium
solution for 1-3 times was higher than that of without selenium spraying under low temperature stress，and the
contents of malondialdehyde and hydrogen peroxide were all decreased．The effect of spraying twice was the best．
To sum up，the suitable selenium concentration（3 mg·L^-1）and spraying times（twice） can reduce the damage
caused by low temperature stress to certain extent，thus having improved the cold resistance of potato seedlings．

Key words: Potato Seedling, Selenium, Low temperature stress, Cold resistance physiology