两种短命植物种子萌发特性和幼苗生理的研究

Study on Seed Germination Characteristics and Seedling Physiological of Two Ephemera Plants

研究了两种短命植物卷果涩芥(Malcolmia scorpioides)和四齿芥(Tetracme quadricornis)种子在不同处理条件下的萌发情况,并对卷果涩芥和四齿芥幼苗进行NaCl胁迫,测定了两种植物幼苗超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及丙二醛(MDA)含量。结果表明:卷果涩芥和四齿芥种子自然萌发率不足15%,通过赤霉素(GA3)处理和刺破种皮的方法可使两者种子的萌发率提高到90%以上;种子萌发的适宜温度在15～30℃,而光照和黑暗对种子的萌发率影响不显著;卷果涩芥对NaCl和PEG-6000的耐受程度比四齿芥更高一些;在相同NaCl浓度和相同时间段胁迫下,卷果涩芥幼苗的SOD、POD、CAT活性均高于四齿芥,而其MDA含量低于四齿芥,并且随NaCl浓度的增加,3种酶活性均为先升高后降低的趋势,而MDA含量一直处于上升的趋势。

The seed of two ephemera plants Malcolmia scorpioides and Tetracme quadricornis were used in germination experiments to investigate the effects of different conditions on germination.The activeties of SOD,POD,CAT and MDA contents were detected after treated with NaCl.Results showed that the germination rate of the two plants was less than 15%,but dealing with GA3 or puncturing the seed coat could elevate the germination rate to 90%.The best seed germination temperature of the two plant was between 15 ℃ to 30 ℃.However,light has little effect on the germination.Malcolmia scorpioides has more tolerant than Tetracme quadricornis after treated with NaCl and PEG-6000.Under the same concentration and treating time with NaCl,the activity of SOD,POD and CAT in Malcolmia scorpioides was higher than that of Tetracme quadricornis,but the quantity of MDA was lower.With the concentration of NaCl enhancing,the activity of the three enzymes in the two ephemera plants first up and then down,but the quantity of MDA was always up.