Rose plants are one of the most important horticultural crops, whose commercial value mainly depends on long-distance transportation, and wounding and ethylene are the main factors leading to their quality decline and accelerated senescence in the process. However, underlying molecular mechanisms of crosstalk between wounding and ethylene in the regulation of flower senescence remain poorly understood. In relation to this, transcriptome analysis was performed on rose flowers subjected to various treatments, including control, wounding, ethylene, and wounding- and ethylene- (EW) dual treatment. A large number of differentially expressed genes (DEGs) were identified, ranging from 2,442 between the ethylene- and control-treated groups to 4,055 between the EW- and control-treated groups. Using weighted gene co-expression network analysis (WGCNA), we identified a hub geneRhWRKY33(rchiobhmchr5g0071811), accumulated in the nucleus, where it may function as a transcription factor. Moreover, quantitative reverse transcription PCR (RT-qPCR) results showed that the expression ofRhWRKY33was higher in the wounding-, ethylene, and EW-treated petals than in the control-treated petals. We also functionally characterized theRhWRKY33gene through virus-induced gene silencing (VIGS). The silencing ofRhWRKY33significantly delayed the senescence process in the different treatments (control, wounding, ethylene, and EW). Meanwhile, we found that the effect ofRhWRKY33-silenced petals under ethylene and EW dual-treatment were stronger than those under wounding treatment in delaying the petal senescence process, implying thatRhWRKY33is closely involved with ethylene and wounding mediated petal senescence. Overall, the results indicate thatRhWRKY33positively regulates the onset of floral senescence mediated by both ethylene and wounding signaling, but relies heavily on ethylene signaling.

Light is an important environmental signal that governs plant growth, development, and metabolism. Constitutive photomorphogenic 1 (COP1) is a light signaling component that plays a vital role in plant light responses. We isolated the COP1 gene (LoCOP1) from the petals of Lilium ‘Siberia’ and investigated its function. The LoCOP1 protein was found to be the most similar to Apostasia shenzhenica COP1. LoCOP1 was found to be an important factor located in the nucleus and played a negative regulatory role in floral scent production and emission using the virus-induced gene silencing (VIGS) approach. The yeast two-hybrid, β-galactosidase, and bimolecular fluorescence complementation (BiFC) assays revealed that LoCOP1 interacts with LoMYB1 and LoMYB3. Furthermore, light modified both the subcellular distribution of LoCOP1 and its interactions with LoMYB1 and MYB3 in onion cells. The findings highlighted an important regulatory mechanism in the light signaling system that governs scent emission in Lilium ‘Siberia’ by the ubiquitination and degradation of transcription factors via the proteasome pathway.

Rosa hybrida is one the most commonly cultivated ornamental plant of economic importance and faces major challenges under heat stress. Melatonin has been widely shown to regulate plant stress response; however, the exact mechanism involved in heat stress in R. hybrida has yet to be determined. Here, we observed that R. hybrida in vitro plantlets supplemented with melatonin in the culture medium exhibited higher chlorophyll content, relative ion leakage, and fresh weight after 12 d of high-temperature treatment; the optimal concentration was established at 5 mg/L. Using molecular and biochemical techniques, we explored the roles of a melatonin synthase gene RhCOMT1, which expression was influenced by heat stress and melatonin. RhCOMT1 was located in the nuclear-cytoplasmic under ambient conditions, while heat stress translocated the distribution of RhCOMT1 to chloroplasts. Overexpression of RhCOMT1 in rose petal enhanced thermotolerance, and silencing of RhCOMT1 reduced thermotolerance via affect H₂O₂ content and relative ion leakage. These findings collectively emphasize the pivotal role of melatonin in enhancing thermotolerance to R. hybrida by alleviation of oxidative stress, through modulation of RhCOMT1 expression and location.

In taxonomy, qualitative methods are commonly used to analyze morphological characters, which can lead to dramatic changes in higher taxa. Geometric morphometrics (GM) has proven to be useful for discriminating species in various taxonomy groups. However, the application of geometric morphometrics in supraspecies classification is relatively scarce. In this study, we tested the controversial two subgenera classification of Chaetocnema with geometric morphometrics; a total of 203 Chaetocnema species representing 50% of all known species from around the world were selected for the analysis. We analyzed the shape of the pronotum, elytron, head, aedeagus, and spermatheca. The results showed that the two traditional subgenera distinctly differed from each other; therefore, we propose using two subgenera arrangements to facilitate the understanding and taxonomy of the Chaetocnema species (especially in the Oriental, Palearctic, and Nearctic regions). Additionally, the morphological diversity of the abovementioned structures of Chaetocnema was analyzed, and it was found that the highest morphological diversity was in the spermatheca, which was greater than that in the aedeagus. Our research demonstrated that GM could be useful for detecting morphological delimitation of the supraspecies taxa. It also showed that GM methods are applicable to insects as small as 2 mm in body size.

Blaiseus Fleutiaux, 1931 is a distinct elaterid genus and readily distinguishable from other Elateridae groups by the strongly flattened fossorial protibia, enlarged femora and tibiae, and the enormously broadened median lobe of genitalia. This study describes and illustrates the Blaiseus dinghuensis Ruan, Qiu & Xie sp. nov. from Guangdong province, China. In addition, an observation of the jumping performance of the new species is made. This represents the third known species of the genus Blaiseus from China and the 12th recognized worldwide.