We investigated the influence of photoperiodic light spectrum, inducing different phytochrome photoequilibria (PPE) at plant level, on photosynthesis, metabolic profiling, plant growth and flowering of Ranunculus asiaticus L. hybrids, MBO and MDR with different flowering earliness, grown in glasshouse from rehydrated dry tuberous roots. Plants were exposed to three photoperiodic treatments (day extension to 14 h), compared to natural day length (NL): white fluorescent light (PPE 0.84), and LEDs Red:Far Red light at 3:1 ratio (PPE 0.84) and 1:3 ratio (PPE 0.63). We discuss the results also compared to data on plants from rehydrated and vernalized roots previously reported in Modarelli et al., 2000a.

Leaf gas exchanges and quantum yield of PSII electron transport were higher in MDR than in MBO, whereas non-photochemical quenching showed the opposite behaviour. In MDR, R:FR 3:1 light was the most effective in promoting stomatal conductance, while it reduced photochemistry and increased heat dissipation compared to other treatments. Under NL, leaf area was greater in MBO while flowering earliness and flower stems were similar in the hybrids. Photoperiodic treatments did not influence the plant growth while anticipated flowering in both the hybrids.

In both the hybrids, lighting did not change the content of chlorophylls, carotenoids, glucose and sucrose. The greater number and expansion of leaves in MBO, except under R:FR 3:1, was accompanied by a lower photosynthetic capacity per leaf area. Conversely, in MDR, with lower leaf number, area and DW, an interesting increase of N-containing metabolites (i.e. chlorophylls and amino acids) occurred, thus exerting a positive effect on photosynthetic rate.

我们研究了光周期光光谱的影响，在工厂级别诱导不同光敏色素photoequilibria（PPE），对光合作用，代谢谱，植物生长和开花毛茛胭脂L.杂种，MBO和MDR具有不同开花早熟，在温室中生长，从再水化干燥块根。与自然日长 (NL) 相比，植物暴露于三种光周期处理（日延长至 14 小时）：白色荧光灯 (PPE 0.84) 和 LED 红光：远红光比 3:1 (PPE 0.84) 和 1 :3 比率（PPE 0.63）。我们还讨论了与之前在 Modarelli 等人，2000a 中报道的来自再水化和春化根的植物数据进行比较的结果。

MDR 中的叶气体交换和 PSII 电子传输的量子产率高于 MBO，而非光化学猝灭显示出相反的行为。在 MDR 中，R:FR 3:1 光在促进气孔导度方面最有效，同时与其他处理相比，它减少了光化学并增加了散热。在NL下，MBO的叶面积更大，而杂种的开花早熟和花茎相似。光周期处理不影响植物生长，同时预期两种杂种的开花。

在这两种杂交种中，光照都没有改变叶绿素、类胡萝卜素、葡萄糖和蔗糖的含量。除了在 R:FR 3:1 下，MBO 中叶子的数量和扩张更多，伴随着每叶面积较低的光合能力。相反，在 MDR 中，随着叶数、面积和干重较低，含氮代谢物（即叶绿素和氨基酸）出现有趣的增加，从而对光合速率产生积极影响。