Background: Cadmium (Cd) is a serious heavy metal (HM) soil pollutant. To alleviate or even eliminate HM pollution in soil, environmental-friendly methods are applied. One is that special plants are cultivated to absorb the HM in the contaminated soil. As an excellent economical plant with ornamental value and sound adaptability, V. bonariensis could be adapted to this very situation. In our study, the Cd tolerance in V. bonariensis was analyzed as well as an overall analysis of transcriptome. Results: In this study, the tolerance of V. bonariensis to Cd stress was investigated in four aspects: germination, development, physiological changes, and molecular alterations. The results showed that as a non-hyperaccumulator, V. bonariensis did possess the Cd tolerance and the capability to concentration Cd. Under Cd stress, all 237, 866 transcripts and 191, 370 unigenes were constructed in the transcriptome data of V. bonariensis roots. The enrichment analysis of gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed that differentially expressed genes (DEGs) under Cd stress were predominately related to cell structure, reactive oxygen species (ROS) scavenging system, chelating reaction and secondary metabolites, transpiration and photosynthesis. DEGs encoding lignin synthesis, chalcone synthase (CHS) and anthocyanidin synthase (ANS) were prominent in V. bonariensis under Cd stress. The expression patterns of 10 DEGs, validated by quantitative real-time polymerase chain reaction (qRT-PCR), were in highly accordance with the RNA-Sequence (RNA-Seq) results. The novel strategies brought by our study was not only benefit for further studies on the tolerance of Cd and functional genomics in V. bonariensis, but also for the improvement molecular breeding and phytoremediation.

Lysine crotonylation is a protein post-translational modification that has been newly discovered in recent years. There are few studies on the lysine crotonylation of proteins in plants, and their functions in response to cold stress are still unclear. In this study, the chrysanthemum (Chrysanthemum morifolium Ramat.) glutathione peroxidase (GPX) gene was selected and named DgGPX1, and was found to be responsive to low temperature. Overexpression of DgGPX1 improved the cold resistance of transgenic chrysanthemum by increasing GPX activity to reduce the accumulation of reactive oxygen species (ROS) under low-temperature conditions. Furthermore, the level of DgGPX1 lysine crotonylation at lysine (K) 220 decreased under low temperature in chrysanthemum. Lysine decrotonylation of DgGPX1 at K220 further increased GPX activity to reduce ROS accumulation under cold stress, and thereby enhanced the cold resistance of chrysanthemum. The above results show that lysine decrotonylation of DgGPX1 at K220 increases GPX activity to resist cold stress in chrysanthemum.

Our study utilized 374 geographical distribution records of H. mutabilis and 19 bioclimatic factors, employing the MaxEnt model and the Geographic Information System (ArcGIS). The key environmental variables influencing the suitable distribution areas of H. mutabilis were analyzed through the comprehensive contribution rate, permutation importance, and Pearson correlation coefficient. Based on this analysis, the contemporary and future suitable distribution areas and their extents were predicted. The results indicate that the key limiting factor affecting the suitable distribution areas of H. mutabilis is the precipitation of the driest month (bio14), with secondary factors being annual precipitation (bio12), annual mean temperature (bio1), and annual temperature range (bio7). Under contemporary climate conditions, the total suitable area for H. mutabilis is approximately 2,076,600 km², primarily concentrated in the tropical and subtropical regions of southeastern China. Under low-to-medium-emission scenarios (SSP1-2.6, SSP2-4.5), the total suitable area of H. mutabilis shows a trend of first decreasing and then increasing compared to the current scenario. In contrast, under high-emission scenarios (SSP5-8.5), it exhibits a trend of first increasing and then decreasing. The spatial pattern changes indicate that the retention rate of suitable areas for H. mutabilis ranges from 95.28% to 99.28%, with the distribution centers primarily located in Hunan and Guizhou provinces, showing an overall migration trend towards the west and north. These findings suggest that H. mutabilis possesses a certain level of adaptability to climate change. However, it is crucial to consider regional drought and sudden drought events in practical cultivation and introduction processes. The results of our study provide a scientific basis for the rational cultivation management, conservation, and utilization of germplasm resources of H. mutabilis.

Soil salinity represents a major constraint in the growth of chrysanthemum. Therefore, improving salinity tolerance of chrysanthemum has become an important research direction in tolerance breeding. Multiprotein bridging factor 1 (MBF1) is an evolutionarily highly conserved transcriptional co-activator in archaea and eukaryotes and has been reported to play important roles to respond to abiotic stresses. Here, a MBF1 gene induced by salt stress was isolated and functionally characterized from Dendranthema grandiflorum and name as DgMBF1. Overexpression of DgMBF1 in chrysanthemum increased the tolerance of plants to high salt stress compared to wild type (WT). It also showed fewer accumulations of hydrogen peroxide (H₂O₂), superoxide anion (O₂⁻), higher activities of antioxidant enzymes, more content of proline and soluble sugar (SS) and more favorable K⁺/Na⁺ ratio than those of WT under salt stress. In addition, the expression level of genes related to antioxidant biosynthesis, proline biosynthesis, glyco-metabolism and K⁺/Na⁺ homeostasis was statistically significant higher in the DgMBF1-overexpressed lines than that in WT. These results demonstrated that DgMBF1 is a positive regulator in response to salt stress and could serve as a new candidate gene for salt-tolerant plant breeding.

As an important part of heat shock response module, heat shock proteins (HSP) play an important role in plant defense response against heat stress; however, the involvement of the majority of the HSP family members against other abiotic stresses remains poorly understood. In the present study, LrHSP17.2 was identified and its function against abiotic stress was analyzed. The expression level of LrHSP17.2 was significantly induced by heat. Heterologous transgenes of LrHSP17.2 showed that LrHSP17.2 can increase the activity of catalase, peroxidase, superoxide dismutase to removes excess reactive oxygen species (ROS), maintain the stability of the membrane structure, and regulate genes related to antioxidant enzymes and defense under abiotic stress. In addition, LrHSP17.2 could be regulated by exogenous abscisic acid and melatonin, and the related hormone synthesis genes of transgenic plants were significantly up-regulated under heat stress. Taken together, our results revealed that LrHSP17.2 is involved in regulating abiotic stress responses by regulating ROS scavenging and stress-related genes in Lilium regale.