红蓝光质对芹菜碳氮代谢及其关键酶活性的影响

Effects of Red and Blue Light Quality on the Metabolites and Key Enzyme Activities of Carbon-Nitrogen Metabolism in Celery

为了探明红蓝光对芹菜生长的调控机理,以‘津南实芹1号’为试材,白光(W)处理为对照(CK),研究红蓝LED光质对芹菜碳氮代谢及其相关酶活性的影响。结果表明:白+红(WR)和白+红+蓝(WRB)处理芹菜的光合速率(Pn)及Ru BP羧化酶(Ru BPCase)活性显著高于CK,白+蓝(WB)处理的Pn低于CK,但Ru BPCase活性高于CK。各处理相比,碳代谢产物多以WR处理的最高,WRB处理的其次,WB处理的最低。WR处理的蔗糖磷酸合成酶(SPS)活性显著高于CK,蔗糖合成酶(SS)活性明显低于CK;WB处理的SS活性较高。WR处理的总氮含量及谷氨酰胺酶(GS)活性显著高于CK,而蛋白质和氨基酸含量明显低于CK;WB处理的蛋白质含量较高,氨基酸含量较低,硝酸还原酶(NR)、GS和谷氨酸合成酶(GOGAT)活性明显高于CK;WRB处理的总氮和蛋白质含量及NR和GS活性均高于CK。可见,增加红光比例可促进芹菜碳的同化、转化及氮的吸收,加速物质积累,但对蛋白质的合成有一定的抑制作用;增加蓝光比例可使芹菜氮代谢增强,但碳的积累代谢下降,因此叶柄伸长受抑,单株产量降低。

The purpose of this paper is to elucidate the regulating mechanism of red and blue light quality on growth of celery. The effects of red and blue LED light quality on the metabolites and key enzyme activities of carbon-nitrogen metabolism in celery plants with ‘Jinnan Shiqin 1＇ as materials were investigated. The white light（W） treatment was used as the control. The results showed that white＋red（WR） and white＋red＋blue（WRB） lights increased the photosynthetic rate（Pn） and Ru BP carboxylase（Ru BPCase） activity, white＋blue（WB） light also increased the Ru BPCase activity, but decreased Pn signifi cantly, in comparison with the control. Carbon metabolites of WR treatment was mostly the highest, and WB treatment was the lowest among the four treatments. WR treatment plants showed a significantly higher sucrose phosphate synthase（SPS） activity, whereas a lower sucrose synthetase（SS） activity than the control plants. The SS activity of the WB treatment was markedly higher than that of the control. However, no signifi cant difference was observed in SPS activity between WB and the control. WR treatment plants showed an increase in total nitrogen content and glutaminase（GS） activity, a decrease in protein and amino acid contents than the control plants. Compared with the control, WB treatment revealed obviously higher protein content and activities of nitrate reductase（NR）, GS and glutamate synthase（GOGAT）, while lower amino acid content. The NR and GS activities were higher in WRB treated plants than in control plants. These data suggest that increased red light can improve the carbon assimilation and conversion, nitrogen absorption, and matter accumulation, but inhibit protein synthesis in celery. Increased the proportion of blue light promotes the nitrogen metabolism in celery leaves, but decreases the carbon accumulation, and therefore inhibits the prolongation of the petiole and decreases the yield.