Nitrogen (N) plays an important role in the growth cycle of the potato, and is an important guarantee of yield and quality. Rational N application is one of the key ways to improve a crop’s high and stable yield and economic and environmental benefits. The N nutrition level of potato regulates the gene expression of enzymes related to the N metabolism pathway, which shows the change of the activity of key enzymes in N metabolism, and finally realizes the regulation of N absorption and utilization. In this study, the key enzyme genes and enzyme activity of different genotypes of potato under different N supply treatments were identified, which laid a foundation for further exploration of the functions of each gene in the potato N metabolism pathway and provided theoretical basis for rational N application. The results showed that the relative expression levels of StNRT1.5, StNR, StNiR in leaves, StNRT2.5, StNRT2.4, StGS1-2 in roots and StNRT2.7, StGS1-3, StGS2, StGS1-4, StFd-GOGAT in leaves and roots showed that the levels of N-inefficient potato Atlantic (A) were higher than the N-efficient potato Yanshu 4 (Y), while the relative expression levels of StNRT2.5, StGS1-2 in leaves, StNRT1.5StNR, StNiR in roots and StGDH, StNADH-GOGAT in leaves and roots showed that levels in Yanshu 4 (Y) were higher than in Atlantic (A). At the same time, we especially found that the GDH activity in the leaves of the two genotypes of potato were higher at low N levels. Additionally, the activity of NR and NiR, and the activity of GS and GOGAT were correlated. In addition, the changes of key enzymes in different N metabolism showed a certain continuity with the advancement of growth and development, and some gene expression rules and enzyme activity changes also showed a certain consistency.

Background: Hosta plantaginea (Lam.) Aschers (HPA), a species in the family Liliaceae, is an important landscaping plant and herbaceous ornamental flower. However, because the flower has only two colors, white and purple, color matching applications are extremely limited. To date, the mechanism underlying flower color regulation remains unclear. Methods: In this study, the transcriptomes of three cultivars—H. plantaginea (HP, white flower), H. Cathayana (HC, purple flower), and H. plantaginea ‘Summer Fragrance’ (HS, purple flower)—at three flowering stages (bud stage, initial stage, and late flowering stage) were sequenced with the Illumina HiSeq 2000 (San Diego, CA, USA). The RNA-Seq results were validated by qRT-PCR of eight differentially expressed genes (DEGs). Then, we further analyzed the relationship between anthocyanidin synthase (ANS), chalcone synthase (CHS), and P450 and the flower color regulation by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Eukaryotic Orthologous Groups (KOG) network and pathway enrichment analyses. The overexpression of CHS and ANS in transgenic tobacco petals was verified using qRT-PCR, and the petal colors associated with the overexpression lines were confirmed using absorbance values. Results: Over 434,349 transcripts were isolated, and 302,832 unigenes were identified. Additionally, through transcriptome comparisons, 2098, 722, and 606 DEGs between the different stages were found for HP, HC, and HS, respectively. Furthermore, GO and KEGG pathway analyses showed that 84 color-related DEGs were enriched in 22 pathways. In particular, the flavonoid biosynthetic pathway, regulated by CHS, ANS, and the cytochrome P450-type monooxygenase gene, was upregulated in both purple flower varieties in the late flowering stage. In contrast, this gene was hardly expressed in the white flower variety, which was verified in the CHS and ANS overexpression transgenic tobacco petals. Conclusions: The results suggest that CHS, ANS, and the cytochrome P450s-regulated flavonoid biosynthetic pathway might play key roles in the regulation of flower color in HPA. These insights into the mechanism of flower color regulation could be used to guide artificial breeding of polychrome varieties of ornamental flowers.

Physalis philadelphica, a member of the Solanaceae family, commonly known as Physalis, is a one-year-old herbaceous plant with both medicinal and edible properties, as well as ornamental value. At present, only limited research is available on the flower color of P. philadelphica. This study aimed to elucidate the metabolic characteristics underlying the flower color of P. philadelphica and to identify key genes associated with flower color metabolism. We selected two representative varieties of P. philadelphica with significant differences in flower color, namely, “Tieba” (yellow flower) and “Qingjin” (yellow-purple flower), as the experimental materials. The analysis of related pigment components and the determination of relative content by high-performance liquid chromatography were conducted to investigate the flower color-related metabolic pathways of P. philadelphica. Through next-generation sequencing, these pathways were further investigated for the characteristics and differentially expressed genes (DEGs) associated with flower color formation. The results of the research show that: Anthocyanin is the main component of petal coloring of P. philadelphica var. Qingjin, while malvidin pigment, pelargonidin, delphinidin, and cyanidin are the main components of flower color intensity. Carotenoids are the main components of the petal coloring of P. philadelphica var. Tieba and β-carotene is the main component of flower color intensity. Comparing different developmental stages of these two kinds of Physalis pubescens, we identified two key transcription factors (TFs) (eBP and STAT) that were involved in the inhibition of anthocyanin synthesis and regulate the inhibition of pf05G124640 (dihydroflavonol 4-reductase) and pf09G224140 (anthocyanin synthase) in anthocyanin synthesis. One heat shock transcription factor was found to regulate the flavonoid and flavonol synthesis pathway of pf01G020090 (anthocyanin 3-O-glucosyltransferase); two key TFs (NAC and G2-Like), pf10G255070 (isoricin dehydrogenase) and pf09G237080 (abscisic acid 8′-hydroxylase), played important roles in carotene biosynthesis. This study provides new insights for further exploration of the genetic diversity of petal coloring in P. philadelphica and establishes a foundation for subsequent molecular breeding efforts.

Physalis pubescens and Physalis alkekengi, members of the Physalis genus, are valued for their delicious and medicinal fruits as well as their different ripened fruit colors—golden for P. pubescens and scarlet for P. alkekengi. This study aimed to elucidate the pigment composition and genetic mechanisms during fruit maturation in these species. Fruit samples were collected at four development stages, analyzed using spectrophotometry and high-performance liquid chromatography (HPLC), and complemented with transcriptome sequencing to assess gene expression related to pigment biosynthesis. β-carotene was identified as the dominant pigment in P. pubescens, contrasting with P. alkekengi, which contained both lycopene and β-carotene. The carotenoid biosynthesis pathway was central to fruit pigmentation in both species. Key genes pf02G043370 and pf06G178980 in P. pubescens, and TRINITY_DN20150_c1_g3, TRINITY_DN10183_c0_g1, and TRINITY_DN23805_c0_g3 in P. alkekengi were associated with carotenoid production. Notably, the MYB-related and bHLH transcription factors (TFs) regulated zeta-carotene isomerase and β-hydroxylase activities in P. pubescens with the MYB-related TF showing dual regulatory roles. In P. alkekengi, six TF families—bHLH, HSF, WRKY, M-type MADS, AP2, and NAC—were implicated in controlling carotenoid synthesis enzymes. Our findings highlight the intricate regulatory network governing pigmentation and provide insights into Physalis germplasm’s genetic improvement and conservation.

The oil bean is a high-quality, economically valuable variety of kidney bean (Phaseolus vulgaris L.) that is widely cultivated in Northeast China. However, the prevalence of anthracnose, caused by a combination of factors, including continuous cropping over many years, has led to significant declines in both yield and quality. The mitogen-activated protein kinase (MAPK) cascade is a highly conserved plant cell signaling pathway that plays a pivotal role in plant growth and development, as well as responses to biotic stress. However, its role in the response of P. vulgaris to anthracnose infection has not previously been reported. We identified and characterized thirteen MAPK genes (PvMAPK01–PvMAPK13) in the P. vulgaris genome. These genes were found on eight of the eleven chromosomes of P. vulgaris, and phylogenetic analyses classified them into four previously established subgroups (A–D). Analysis of the cis-acting elements in their promoter regions revealed the presence of multiple elements associated with light, hormone regulation, stress responses, and growth and development. An analysis of intraspecific collinearity revealed that whole-genome and/or segmental duplication, rather than tandem duplication, has been the primary driver of PvMAPK family expansion in P. vulgaris. Transcriptome data revealed that the PvMAPKs differed in their tissue-specific expression patterns, with PvMAPK05 showing particularly high expression in stems and stem tips and PvMAPK07 and PvMAPK11 showing relatively low expression across all tissues. In general, expression of the PvMAPKs was higher in stems, stem tips, and pods than in other tissues and organs, suggesting that they may be particularly important for regulating stem and pod development. Analysis of the expression of PvMAPKs in field-grown plants infected or uninfected with anthracnose revealed that the relative expression levels of PvMAPK05, PvMAPK07, PvMAPK09, and PvMAPK11 exhibited particularly significant changes in response to anthracnose infection across different varieties, suggesting their potential involvement in the anthracnose response of Phaseolus vulgaris. This study reports the fundamental characteristics of the thirteen MAPK genes in P. vulgaris, documents their expression patterns in diverse tissues, and offers preliminary insights into their responses to anthracnose infection, establishing a foundation for subsequent functional validation.

Pollen viability is a limiting factor in potato hybridization, although it varies considerably among potato varieties. Exploring the molecular basis of pollen viability will give a theoretical foundation for improving hybridization. In this research, we showed that the four StLAT52 genes, namely StLAT52a, StLAT52b, StLAT52c and StLAT52d were the key genes affecting potato pollen viability, and they were only expressed in flowers. It was also noted that these genes were localized in the nucleus. An assessment of protein–protein interactions showed that StLAT52a and StLAT52b proteins, StLAT52a and StLAT52c proteins, and StLAT52b and StLAT52c proteins interacted both in vitro and in vivo. When these genes were transferred into tobacco, the number of pollen grains significantly increased, and the pollen viability increased by almost 10%. In addition, the expression of the StLAT52 genes in tobacco resulted in significant changes in genes associated with the proteasome, ribosome biogenesis and plant hormone signal transduction pathways during the flowering stage. Taken together, this research provided an in-depth understanding of the structure and functions of the LAT52 genes in potatoes and their association with pollen viability. The results of this research can be used as a basis for further exploring the molecular mechanism underlying pollen viability.