外源硒肥对盐碱地油葵幼苗生长和生理特性的影响

摘要

In order to enhance the plant's resistance to environmental stress ,and ensure the normal grow th of plants ,the effects of different selenium concentration on several physiological features of oil sunflower seedling in saline‐alkali soil were studied .The results showed that optimal concentration of Se fertilizer application (200 g·hm‐2 ) promoted plant grow th ,and increased plant height ,stem diameter ,SPAD value and dry matter of oil sunflower seedling ,otherwise inhibited its growth ;with Se fertilizer application MDA content of oil sunflower leaves began to decrease ,and reached the minimum value in Se4(400 g·hm‐2 ) treatment ,decreased by 45 .8%compared to the control treatment ;the content of Pro increased first and then declined ,and reached the high‐est value in Se2(200 g·hm‐2 ) treatment ,increased by 8 .9% .Three kinds of antioxidant enzymes activities all increased first and then decreased .The activities of peroxidase ,catalase and superoxide dismutase reached max‐imun respectively at Se1 ,Se2 ,Se3 .Glutathione content decreased first and then increased ,and reached lowest value in Se2 ,decreased by 16 .5% with CK .Considering the changes in oil sunflower morphological index and physiological indicators of oil sunflower seedling ,soil application of selenium fertilizer of 200 g·hm‐2 could in‐crease the antioxidant capacity of oil sunflower .%为增强植株对环境胁迫的抗性，保证植株的正常生长，采用田间试验，研究不同浓度硒肥对盐碱地油葵幼苗生长及生理指标的影响。结果表明：土施适宜浓度硒肥（200 g·hm‐2）有利于油葵植株生长，可提高油葵植株高、茎粗、SPAD值、干物质等指标，反之则抑制其生长；随着硒浓度的增加，叶片中丙二醛含量开始降低，并在Se4（400 g·hm‐2）处理降到最低值，比对照降低45．8％；叶片脯氨酸含量呈先增加后降低的趋势，在Se2（200 g·hm‐2）处理达最高值，比对照增加8．9％。3种抗氧化酶的活性均呈先增加后降低的趋势，其中过氧化物酶活性、过氧化氢酶活性、超氧化歧化酶活性分别在Se1、Se2、Se3时达最大值，比对照增加了20．1％、12．0％、9．7％。叶片还原型谷胱甘肽含量呈先降低后增加趋势，在Se2（200 g·hm‐2）处理达最低值，比对照降低16．5％。综合考虑油葵形态指标和生理指标的变化，土施200 g·hm‐2硒肥，可提高油葵的抗氧化能力。