海藻酸钠寡糖对菜薹光合特性和碳代谢的影响

Effects of Alginate Derived Oligosaccharide on Photosynthetic Characteristics and Carbon Metabolism of Brassica campestris L.ssp.chinensis var.utilis Tsen et Lee

采用溶液培养,研究海藻酸钠寡糖对菜薹光合特性和碳代谢的影响。结果表明:海藻酸钠寡糖处理可不同程度提高净光合速率(Pn)、水分利用效率(WUE)和CO2羧化效率(CE),增加光饱和点(LSP),并降低光补偿点(LCP),提高初始荧光(Fo)、最大荧光(Fm)、可变荧光(Fv)、光系统II最大光化学效率(Fv/Fm)、电子传递效率(ETR)和非光化学猝灭系数(NPQ)。蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性显著增强,促进蔗糖积累;处理前期转化酶活性有所提高,第6天显著降低,葡萄糖含量也相应下降;淀粉含量随时间延长逐渐增加,纤维素则相反。说明海藻酸钠寡糖可促进光能的捕获及转化,提高其光能利用效率,并改变碳代谢过程,促进碳代谢产物积累。

A hydroponics experiment was used to study the effects of alginate derived oligosaccharides on photosynthetic characteristics and carbon metabolism of Brassica campestris L.ssp.chinensis var.utilis Tsen et Lee.After adding alginate derived oligosaccharides,the net photosynthetic rate（Pn）,water use efficiency（WUE）and CO2carboxylation efficiency（CE） in leaves were improved;an increased light saturation point（LSP）and a decreased light compensation point （LCP） were observed.The minimal fluorescence（Fo）,the maximal fluorescence（Fm）,the variable fluorescence（Fv）,photosystem II maximal photochemical efficiency（Fv/Fm）and its electron transfer rate（ETR）and the non-photochemical quench（NPQ）to some extent was improved.Meanwhile the activity of sucrose phosphate synthase（SPS）and sucrose synthase（SS）increase devidently which facilitated the increase of sucrose contents.In early stage of study,invertase activity alsoincreased significantly,while they decreased significantly at the 6th day;glucose contents also decreased.The starch contents were gradually increased with time,but cellulose contents were contrary.The results suggested the application of alginate derived oligosaccharides could promote the trapping and conversion of light energyin B.campestris L.ssp.chinensis var.utilis Tsen et Lee,enhance light utilized efficiency,change the process of the carbon metabolism and facilitate the accumulation of carbon metabolism products.