摘要
硫灯或氙灯具有不同的红光/远红光比例(R/FR,前者为1.5,而后者为1)。研究结果表明,硫灯照射下生长的番茄幼苗叶片与太阳光下相似,能正常合成花青素;而氙灯照光生长的番茄幼苗叶片中的花青素合成受到严重抑制,通过分光光度法测定的花青素含量仅为前者的1/9。进一步在硫灯下培养红光/远红光受体(光敏素B族)单突变和双突变的番茄幼苗中,发现单突变体phyB1和双突变体phyB1phyB2的叶片花青素含量显著低于野生型,分别为野生型的1/3和1/15,由此推测花青素合成途径受到了红光/远红光比例的影响。HPLC结果又表明,硫灯和氙灯照光生长的番茄幼苗叶片中黄酮醇总量没有显著差异。我们推测氙灯下番茄幼苗花青素合成过程可能抑制位点是二氢黄酮醇还原酶或白花色素双氧酶两个催化步骤。
Anthocyanidin accumulation in tomato seedling leaves exposed to different R/FR ratio light condition was studied.Spectrophotometric analysis suggested that tomato seedling leaves grown in high R/FR (1.5) condition could normally synthesize anthocyanidin,while the anthocyanidin synthesis in tomato seedling leaves grown in low R/FR (1.0) condition was reduced to 1/9 that in high R/FR condition.Meanwhile,it was found that the anthocyanidin content in single mutant phyB1 and double mutant phyB1phyB2 tomato seedling leaves was significantly reduced compared to the wild type,only 1/3 and 1/5 of the latter,respectively.On the other hand,anthocyanidin content in single mutant phyA tomato seedling leaves was slightly higher than that in WT leaves.Therefore,it could be concluded that the anthocyanin synthesis was regulated by red/far-red ratio and phytochrome B family.HPLC assay showed no significant difference in total flavonol content in tomato seedling leaves grown in either high or low R/FR condition.Accordingly,we speculated that either or both of DFR and LDOX-mediated steps of anthocyanidin synthesis were inhibited in tomato seedling leaves grown in low R/FR condition.
出处
《西北植物学报》
CAS
CSCD
2004年第10期1773-1778,共6页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家重点基础研究发展规划资助项目(G1998010100)
国家自然科学基金项目资助(30170079)
关键词
番茄
花青素
二氢黄酮醇还原酶
白花色素双氧酶
tomato
anthocyanidin
dihydroflavanone reductase (DFR)
leucoanthocyanin dioxygenase (LDOX)
