Plants can be grouped into sun- and shade-type owing to their distinct irradiance adaptation. Aglaonema commutatum is a typical shade-tolerant perennial foliage plant native to South Asia with various leaf colorations. ‘Red’ cultivars are widely used for interior decorations and as courtyard ornamental plants, owing to their unique hue and bi-adaptation of both low and high irradiance. However, the underlying source of ‘red’ pigment-dependent irradiance bi-adaptation remains largely unknown. Therefore, four A. commutatum cultivars were comparatively evaluated in terms of pigment composition and photosynthetic rate under full light (sunlight) or 50% full light (shade) to unveil the relationship between pigmentation and irradiance bi-adaptation. Our results showed that the photosynthetic rate of sun leaves generated from light response curves was significantly correlated with anthocyanin content and chlorophyll in red cultivars, suggesting the influence of anthocyanin–light interactions on the high/low irradiance bi-adaptation of red A. commutatum. This study provides a theoretical basis for further cultivating red foliage A. commutatum cultivars under diverse light conditions.

Background: Plant anthocyanins are a secondary metabolite widely distributed in the roots, stems, leaves, flowers, and fruits of plants, and their synthesis is significantly affected by light intensity. To investigate the synthesis of anthocyanins in Aglaonema commutatum’s leaves under different light intensities is essential. Methods: Using the commonly colored leaf A. commutatum variety ‘Emerald’ as the control group, and the red-leaf varieties ‘Red Ruyi’, ‘Angel’, and ‘Gilly Red’ as the experimental material, three light intensities were set: 254~368 μmol·m⁻²·s⁻¹ (CK), 588~678 μmol·m⁻²·s⁻¹ (T1), and 1125~1267 μmol·m⁻²·s⁻¹ (T2). Results: The changes in anthocyanin content and anthocyanin-related gene expression in the leaves of A. commutatum with different leaf colors under different light intensities were studied. The results show that the anthocyanin content of A. commutatum leaves had a different trend compared to A. commutatum with increasing light intensity, and the appropriate light intensity could significantly promote anthocyanin synthesis after a certain time, and vice-versa. The anthocyanin content of CK and the T1 treatment was 1.14–3.72 times that of the T2 treatment; the photosensitive genes PHYB, CRY, and UVR8 were correlated with the anthocyanin synthesis of ‘Angel’ and ‘Gilly Red’. The anthocyanin structural genes PAL, DFR, and ANS were correlated with the anthocyanin synthesis of ‘Red Ruyi’, ‘Angel’, and ‘Gilly Red’. The anthocyanin transcription factor bHLH was strongly correlated with the anthocyanin synthesis of ‘Angel’. Conclusions: As a byproduct from A. commutatum leaves with ornamental value and potential economic value, this study was helpful to understand the potential mechanism of A. commutatum’s leaves where light intensity regulates anthocyanin synthesis and accumulation.

Background: Environmental conditions, such as photoperiod, affect the developmental response of plants; thus, plants have evolved molecular mechanisms to adapt to changes in photoperiod. In Bougainvillea spp., the mechanism of flower formation underlying flowering control techniques remains poorly understood, and the physiological changes that occur during flower bud formation and the expression of related genes are not yet fully understood. Methods: In this study, we induced flowering of potted Bougainvillea glabra ‘Sao Paulo’ plants under light-control treatments and analyzed their effects on flowering time, number of flower buds, flowering quality, as well as quality of flower formation, which was analyzed using transcriptome sequencing. Results: Light-control treatment effectively induced the rapid formation of flower buds and early flowering in B. glabra ‘Sao Paulo’, with the time of flower bud formation being 119 days earlier and the flowering period extended six days longer than those of the control plants. The light-control treatment caused the bracts to become smaller and lighter in color, while the number of flowers increased, and the neatness of flowering improved. Transcriptome sequencing of the apical buds identified 1235 differentially expressed genes (DEGs) related to the pathways of environmental adaptation, biosynthesis of other secondary metabolites, glycan biosynthesis and metabolism, and energy metabolism. DEGs related to gibberellin metabolism were analyzed, wherein five DEGs were identified between the control and treatment groups. Transcriptomic analysis revealed that the gibberellin regulatory pathway is linked to flowering. Specifically, GA and GID1 levels increased during this process, enhancing DELLA protein degradation. However, decreasing this protein’s binding to CO did not halt FT upregulation, thereby advancing the flowering of B. glabra ‘Sao Paulo’. Conclusions: The findings of our study have implications for future research on photoperiod and its role in controlling flowering timing of Bougainvillea spp.