The red (R) and blue (B) light wavelengths are known to influence many plant physiological processes during growth and development, particularly photosynthesis. To understand how R and B light influences plant photomorphogenesis and photosynthesis, we investigated changes in leaf anatomy, chlorophyll fluorescence and photosynthetic parameters, and ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) and Calvin cycle-related enzymes expression and their activities in sweet pepper (Capsicum annuum L.) seedlings exposed to four light qualities: monochromatic white (W, control), R, B and mixed R and B (RB) light with the same photosynthetic photon flux density (PPFD) of 300 μmol/m2·s. The results revealed that seedlings grown under R light had lower biomass accumulation, CO2 assimilation and photosystem II (PSII) electron transportation compared to plants grown under other treatments. These changes are probably due to inactivation of the photosystem (PS). Biomass accumulation and CO2 assimilation were significantly enriched in B- and RB-grown plants, especially the latter treatment. Their leaves were also thicker, and photosynthetic electron transport capacity, as well as the photosynthetic rate were enhanced. The up-regulation of the expression and activities of Rubisco, fructose-1, 6-bisphosphatase (FBPase) and glyceraldehyde-phosphate dehydrogenase (GAPDH), which involved in the Calvin cycle and are probably the main enzymatic factors contributing to RuBP (ribulose-1, 5-bisphosphate) synthesis, were also increased. Mixed R and B light altered plant photomorphogenesis and photosynthesis, mainly through its effects on leaf anatomy, photosynthetic electron transportation and the expression and activities of key Calvin cycle enzymes.

中文翻译：

---

红光和蓝光对甜椒幼苗叶片解剖，CO2同化和光合电子传递能力的影响。

已知红色（R）和蓝色（B）的光波长会影响植物在生长发育过程中的生理过程，尤其是光合作用。为了了解R和B光如何影响植物的光形态发生和光合作用，我们调查了叶片解剖结构，叶绿素荧光和光合参数以及核糖1、5-双磷酸羧化酶/加氧酶（Rubisco）和卡尔文循环相关酶的表达及其活性的变化。在甜椒（Capsicum annuum L.）幼苗上暴露于四种光质：单色白光（W，对照），R，B和混合的R和B（RB）光，具有相同的光合光子通量密度（PPFD）为300μmol/平方米·秒。结果表明，在R光下生长的幼苗的生物量积累较低，与在其他处理下生长的植物相比，CO2同化和光系统II（PSII）电子传输。这些变化可能是由于光系统（PS）失活所致。B和RB生长的植物，尤其是后一种处理，生物量积累和CO2同化显着丰富。它们的叶子也更厚，并且提高了光合电子传输能力以及光合速率。Rubisco，果糖-1、6-双磷酸酶（FBPase）和甘油醛磷酸脱氢酶（GAPDH）的表达和活性上调，这些酶参与了Calvin循环，可能是促成RuBP（核糖体- 1、5-双磷酸酯）的合成也增加了。R和B混合光改变了植物的光形态发生和光合作用，