【作者】 李倩；

【导师】 梁宗锁； Chieri Kubota；

【作者基本信息】 西北农林科技大学 ， 植物学， 2010， 博士

【摘要】 通过优化光质条件提高经济作物（蔬菜和中药材）产量和品质引起人们的重视,关于光质对植物生长发育的影响进行了较多的研究,但关于光质对植物次生代谢的影响及相关机理了解甚少,不仅如此,大多数研究仅选择了一种或几种光质条件,并未把所有重要的波段（从紫外到红外）在同一条件下进行系统研究,生产应用到目前尚难以进行。本研究通过应用长波紫外、蓝、绿、红、远红光发光二级管（LEDs）配合白色冷荧光灯,分别以生菜（Lactuca sativa L. cv. Red Cross）和丹参（Salvia miltiorrhiza Bunge）为材料研究了不同光质对植物生长及次生代谢物含量的影响规律及机理,为生产应用及相关理论研究提供参考。主要结果如下:一、不同光质对生菜生长及次生代谢物的影响生菜叶片生长及次生代谢物含量受不同光质影响显著:与同等PAR的白光相比较,补充远红光（WFR）处理的生菜茎长、叶片长和叶片宽均显著提高,叶片受光面积扩大,增加了干物质累积,鲜重、干重均显著提高。补充紫外光（WUV）、补充蓝光（WB）、补充绿光（WG）和补充红光（WR）处理对生菜鲜重和干重均无显著影响。在次生代谢物含量方面,WUV处理的生菜叶片中花青素含量显著提高;WB处理的生菜叶片中花青素和类胡萝卜素含量显著提高;WR处理的生菜叶片中总酚酸含量显著提高;WFR处理的生菜叶片花青素、类胡萝卜素以及叶绿素含量显著降低。二、不同强度UV-A对生菜生长及次生代谢物的影响生菜叶片生长及次生代谢物含量受不同强度UV-A影响显著:在PAR为300μmol m^-2 s^-1,与白光相比较,补充UV-A从4.3μmol m^-2 s^-1到20.9μmol m^-2 s^-1并未显著影响植物鲜、干重、类胡萝卜素、抗坏血酸和总酚酸含量。但生菜叶片中花青素含量随补充UV-A强度增加而提高,当补充UV-A强度达15.9μmol m^-2 s^-1时,其差异达到显著水平。三、优化光质条件调控生菜生长及次生代谢生菜叶片生长及次生代谢物含量受光质影响显著,WB/FR和WFR/B均可有效的调控生菜生长及代谢:与同等PAR的白光相比较,WB/FR能够显著提高生菜叶片的鲜重、干重,增加产量,且对叶片中花青素、类胡萝卜素、总酚酸、抗坏血酸以及叶绿素含量无显著影响;WFR/B也能够显著提高生菜叶片的鲜重、干重,增加产量,但叶片中花青素及类胡萝卜素含量显著降低。四、光质影响生菜次生代谢物含量机理研究与同等PAR的白光相比较,WB处理生菜叶片中花青素和类胡萝卜素含量,WR处理显著提高了生菜叶片中总酚酸含量,这是保护酶体系和代谢酶体系共同变化的结果:WB处理的生菜叶片SOD和POD活性显著升高;WR处理POD活性显著升高;CAT活性未受不同光质影响。代谢酶体系酶活性也受到的光质处理的影响,WB处理显著提高了PAL、TAT和PPO活性;WR处理显著提高了TAT和PPO活性。五、光质影响丹参生长及次生代谢规律及机理研究丹参生长及次生代谢物含量受不同光质影响显著:与同等PAR的白光相比较,WB处理使植株株高显著降低;WR处理使丹参根长、根直径、根鲜重和干重分别显著增加。WB和WR显著提高了丹参根系丹酚酸B含量,但丹参酮IIA含量未受光质显著影响。而这种现象是不同光质下丹参体内保护酶和代谢酶体系共同作用的结果:WB处理下SOD、POD、PAL、TAT和PPO活性显著提高;WR处理下POD、TAT和PPO活性显著提高。且种子直播苗比根栽苗对光质敏感。其中第一至第三部分在美国亚利桑那大学完成;第四、五部分在西北农林科技大学完成。更多还原

【Abstract】 The viability of optimizing light quality in increasing plant growth and phytochemical concentration has been focused recently. Fore-researchers studied the effects of light quality on growth of plants but ignored the phytochemical changings, most studies examined only a few selected light qualities at one time and there are no reports examining the effects of all the important components of light quality （UV, B, green （G）, R and RF） affecting plant growth and/or phytochemical accumulation in plants growing under what are otherwise the same environmental conditions.Therefore, using UV-A, blue （B）, green （G）, red （R）, and far-red （FR） light-emitting diodes （LEDs）, we investigated the effects of different supplemental light qualities on phytochemicals and growth of‘Red Cross’baby leaf lettuce （Lactuca sativa L.） and Salvia miltiorrhiza Bunge, furthermore, the mechanism of why phytochemical concentration in plants increased by light quality changing has been studied. Findings from such a study will be useful to better understand the light quality affecting plant phytochemical synthesis, which is an important area in plant biology drawing much attention. The main results were as follows:1. Phytochemical concentration and growth of lettuce plants were significant affected by light quality treatments. The fresh weight, dry weight, stem length, leaf length and leaf width significantly increased with supplemental FR light compare to white light, presumably due to enhanced light interception by enlarged leaf area under supplemental FR light. Plant biomass was not significantly affected with supplemental UV-A, B, G and R treatments. Anthocyanins concentration increased with supplemental UV-A and B, respectively, carotenoids concentration increased with supplemental B, phenolics concentration increased with supplemental R while supplemental FR decreased anthocyanins, carotenoids and chlorophyll concentration compared to those in the white light control.2. Compare to white light control, anthocyanins concentration in lettuce increasing linearly with UV-A PF from 4.3μmol m^-2 s^-1 to 20.9μmol m^-2 s^-1, but xanthophylls,β-carotene, chlorophyll, total phenolics and ascorbic acid concentration in lettuce leaf were not significantly affected.3. Compare to white light control, growth and phytochemical concentrations of lettuce plants were significant improved by an alternative treatment of supplemental blue and far red light. Biomass production of lettuce significantly increased without losing of phytochemical concentration with supplemental blue/far red light. Biomass production of lettuce also significantly increased with supplemental far red / blue light but the anthocyanins and carotenoids concentration were significantly decreased.4. Compare to white light control, anthocyanins and carotenoids concentration were significantly increased with supplemental blue light, and phenolics concentration were significantly increased with supplemental red light, these were caused by the changings of both protective enzyme system and metabolism enzyme system. Enzyme activity of SOD, POD, PAL, TAT and PPO were significant increased by supplemental blue light, and enzyme activity of POD, TAT and PPO were significant increased by supplemental red light.5. Compare to white light control, growth and phytochemical concentration of Salvia miltiorrhiza Bunge were significant affected by light quality treatments. Plant height was significantly decreased with supplemental blue light, and the root length, root diameter, root fresh weight and root dry weight were significantly increased with supplemental red light. Salvianolic acid B concentration in Salvia miltiorrhiza Bunge was significantly increased with supplemental blue and red light, but TanshinoneIIA concentration was not significantly affected with supplemental blue and red light. These were caused by the changings of both protective enzyme system and metabolism enzyme system. Same to results in lettuce, enzyme activity of SOD, POD, PAL, TAT and PPO in Salvia miltiorrhiza Bunge were significant increased by supplemental blue light, and enzyme activity of POD, TAT and PPO were significant increased by supplemental red light.Part 1-3 were conducted at the University of Arizona, USA. Part 4 and 5 were conducted at the Northwest A&F University.更多还原