Search Results (51)

Soil salinity is a major constraint on crop cultivation, affecting millions of hectares of land and increasing drastically worldwide. Identifying sources of tolerance within the crops and their wild relatives is imperative. Recently, Solanum dasyphyllum L. has been identified as source of tolerance to drought for eggplant (S. melongena L.). In this article, the potential use of S. dasyphyllum as a source of tolerance to salinity is investigated through the characterization of young plants’ performance under three salt stress treatments, well water (control), as well as 200 mM and 400 mM NaCl. Biometric parameters such as leaf and radicular biomass, plant height, root length, and biochemical parameters—such as photosynthetic pigments, main ions accumulation, proline, total soluble sugars, malondialdehyde, total phenolics, flavonoids, and antioxidant enzymes’ activity—were quantified. The results showed a certain reduction in leaf and stem plant growth up to 60% in response to extreme salinity, while root biomass was maintained under mid-salt stress. Salt stress caused toxic ions to accumulate in plant organs, up to 1600 mmol g⁻¹ dry weight Na⁺ and a 2250 mmol g⁻¹ dry weight Cl⁻ in leaves under extreme salinity exposure. However, S. dasyphyllum maintained K⁺ levels at around 450 mmol g⁻¹ in leaves and roots and 750 mmol g⁻¹ in stems, indicating a mechanism related to ion transport to cope with ion toxicity. The biochemical response indicated osmotic adjustments and antioxidant activity without the need of activating antioxidant enzymes. S. dasyphyllum has proved to be a valuable genetic tool for new eggplant breeding programs regarding salt stress, with somewhat improved performance regarding biometric parameters and ion transport. Full article

Cytoplasmic male sterility (CMS) is important for commercial hybrid seed production. However, it is still not used in eggplant (Solanum melongena L.), and corresponding regulatory genes and mechanisms of action have not been reported. We report CMS line 327A, which was derived from the hybridization between cultivated and wild eggplants. By looking at different stages of anther development under a microscope, we saw that the 327A anther’s tapetum layer vacuolized during meiosis, which caused abortion. To investigate the 327A CMS regulatory genes, the mitochondrial genomes of 327A and its maintainer line 327B were assembled de novo. It was found that 15 unique ORFs (Open Reading Frame) were identified in 327A. RT-PCR and RT-QPCAR tests confirmed that orf312a and orf172a, 327A-specific ORFs with a transmembrane domain, were strongly expressed in sterile anthers of 327A. In addition, orf312a has a chimeric structure with the ribosomal protein subunit rpl16. Therefore, orf312a and orf172a can be considered strong candidate genes for CMS. Concurrently, we analyzed the characteristics of CMS to develop a functional molecular marker, CMS312, targeting a future theoretical basis for eggplant CMS three-line molecular breeding. Full article

GOLDEN2-like (GLK) transcription factor genes are involved in chloroplast biogenesis during all stages of plant growth and development, as well as in the response to biotic and abiotic stresses. However, little is known about this transcription factor family in eggplant. In this study, we identified 54 GLK genes in the eggplant genome (S. melongena L.) and classified them into seven groups (G1–G7). Structural analysis illustrated that the SmGLK proteins of specific groups are relatively conserved. Cis-acting elements indicated that these genes are likely to be involved in multiple responses stimulated by light, phytohormones, and abiotic stress. Collinear analysis indicated that expansion of the SmGLK gene family primarily occurred through segmental duplication. Tissue-specific expression analysis revealed that SmGLKs were preferentially expressed in leaves, fruits, and seeds. Further screening of SmGLK genes revealed their differential expression under various treatments. Notably, SmGLK18 was significantly responsive to multiple phytohormones and stress treatments, whereas SmGLK3 and SmGLK12 were highly induced by ABA, IAA, SA, and drought treatments. Our study provides new information on the eggplant GLK family systematically and comprehensively. For the first time, we propose that SmGLK18 may play a key role in improving heat resistance. This study provides valuable candidate gene resources for further functional research and will benefit eggplant molecular breeding. Full article

To assess the biocontrol potential of Nigrospora oryzae against Solanum rostratum, the effects of different medium components and fermentation conditions on the biomass of N. oryzae were investigated to determine the optimal medium composition and fermentation conditions. Subsequently, the pathogenicity of S. rostratum increased after artificial inoculation of S. rostratum with N. oryzae. Additionally, the safety of N. oryzae fermentation on seven crops were evaluated. The results revealed that the optimal shake flask culture ratio for N. oryzae was lactose:glycerol:yeast extract:(NH₄)₂SO₄ = 2:2:1:2. The optimal fermentation conditions were as follows: 15 mL of inoculum, 75 mL of fermentation liquid in a 150 mL shake flask, an initial pH of 5.0, a culture temperature of 20 °C, and 4 days of culture. The disease index of S. rostratum after spraying with N. oryzae fermentation agent was 60.00, indicating strong pathogenicity to S. rostratum. Safety evaluation revealed that N. oryzae exhibited no symptoms on Zea mays, S. melongena, Festuca arundinacea, Bromus inermis, or Medicago sativa but showed moderate susceptibility to Triticum aestivum and S. lycopersicum. This study represents the first exploration of the biocontrol potential of N. oryzae against S. rostratum. These findings suggest the potential of N. oryzae for development as a microbial herbicide targeting S. rostratum. Full article

TIR1/AFB proteins are a class of auxin receptors with key roles in plant development and biotic and abiotic stress responses; several have been identified as targets of the auxin-mimicking herbicide picloram. In this study, we identified five putative TIR1/AFB gene family members in the important vegetable crop Solanum melongena (eggplant) and characterized them using bioinformatics tools and gene expression analyses. Phylogenetic analysis of the TIR1/AFBs classified them into three subgroups based on their Arabidopsis and Solanum lycopersicum homologs. AFB6 homologs were present only in S. melongena and S. lycopersicum, whereas AFB2/3 homologs were found only in Arabidopsis. One pair of S. melongena TIR1 homologs were located in syntenic regions in the genome and appeared to have arisen by segmental duplication. Promoter analysis revealed 898 cis-elements in the TIR1/AFB promoters, 125 of which were related to hormones, stress, light, or growth responses, but only SmAFB5 had a cis-acting regulatory element involved in auxin responsiveness (AuxRR-core). RNA sequencing and expression profiling showed that the TIR1/AFB genes were differentially expressed at different growth stages and in response to light, temperature, and drought. Only SmTIR1A expression was significantly induced by picloram treatment and different growth stages. TIR1/AFB expression is regulated by microRNAs (miRNAs) in other plant species, and we identified 6 or 29 miRNAs that potentially targeted the five TIR1/AFB genes on the basis of comparisons with S. lycopersicum and S. tuberosum miRNAs, respectively. Three-dimensional protein structure predictions revealed that all the TIR1/AFB proteins were very similar in structure, differing only in the numbers of alpha helices and in one angle linking an α helix and a β sheet. For measuring the function of TIR1/AFB genes in response to drought, SmAFB5 was selected, and knockdown by virus-induced gene silence (VIGS) 35S::SmAFB5 lines showed resistance to drought compared to controls. These analyses provide insight into the potential functions of TIR1/AFBs during growth and in response to stress; they highlight differences among the SmTIR1/AFBs that may be useful for eggplant breeding. Full article

Aubergine (Solanum melongena L.) (Solanaceae) is a widespread crop in the Mediterranean basin. Verticillium dahliae is one of the main soil-borne pathogens affecting the aubergine crop. Its control has traditionally been achieved by soil fumigation with chemical disinfectants. Restrictions on the use of chemical fumigants have led to the search for solutions in genetic resistance using rootstocks. In southeastern Spain, aubergines are grafted for the control of V. dahliae. Two Solanum torvum rootstocks (Hugo F1 and Torpedo) and a Solanum melongena hybrid (Javah F1) were tested against five isolates of V. dahliae obtained from grafted (A1 and A2) and ungrafted (Vd8, Vd17 and Vd66) aubergines compared with the susceptible cultivar Larne F1 under controlled conditions. Isolates from grafted plants infected all three rootstocks, with differences observed in the percentage of plants with symptoms and in the disease symptom severity. Three strains isolated from the ungrafted aubergines (Vd8, Vd17 and Vd66) infected Javah F1 rootstock. The Hugo F1 and Torpedo rootstocks showed a high level of resistance to V. dahliae, while Javah F1 was susceptible to the pathogen. The Hugo F1 and Torpedo rootstocks are suitable for mitigating the effects of Verticillium wilt in Mediterranean aubergine crops. Understanding the nature of the resistance from S. torvum could enhance the benefits of grafting or facilitate the introduction of resistance into commercial cultivars. Full article

Anthocyanins are ubiquitous pigments derived from the phenylpropanoid compound conferring red, purple and blue pigmentations to various organs of horticultural crops. The metabolism of flavonoids in the cytoplasm leads to the biosynthesis of anthocyanin, which is then conveyed to the vacuoles for storage by plant glutathione S-transferases (GST). Although GST is important for transporting anthocyanin in plants, its identification and characterization in eggplant (Solanum melongena L.) remains obscure. In this study, a total of 40 GST genes were obtained in the eggplant genome and classified into seven distinct chief groups based on the evolutionary relationship with Arabidopsis thaliana GST genes. The seven subgroups of eggplant GST genes (SmGST) comprise: dehydroascorbate reductase (DHAR), elongation factor 1Bγ (EF1Bγ), Zeta (Z), Theta(T), Phi(F), Tau(U) and tetra-chlorohydroquinone dehalogenase TCHQD. The 40 GST genes were unevenly distributed throughout the 10 eggplant chromosomes and were predominantly located in the cytoplasm. Structural gene analysis showed similarity in exons and introns within a GST subgroup. Six pairs of both tandem and segmental duplications have been identified, making them the primary factors contributing to the evolution of the SmGST. Light-related cis-regulatory elements were dominant, followed by stress-related and hormone-responsive elements. The syntenic analysis of orthologous genes indicated that eggplant, Arabidopsis and tomato (Solanum lycopersicum L.) counterpart genes seemed to be derived from a common ancestry. RNA-seq data analyses showed high expression of 13 SmGST genes with SmGSTF1 being glaringly upregulated on the peel of purple eggplant but showed no or low expression on eggplant varieties with green or white peel. Subsequently, SmGSTF1 had a strong positive correlation with anthocyanin content and with anthocyanin structural genes like SmUFGT (r = 0.9), SmANS (r = 0.85), SmF3H (r = 0.82) and SmCHI2 (r = 0.7). The suppression of SmGSTF1 through virus-induced gene silencing (VIGs) resulted in a decrease in anthocyanin on the infiltrated fruit surface. In a nutshell, results from this study established that SmGSTF1 has the potential of anthocyanin accumulation in eggplant peel and offers viable candidate genes for the improvement of purple eggplant. The comprehensive studies of the SmGST family genes provide the foundation for deciphering molecular investigations into the functional analysis of SmGST genes in eggplant. Full article

The eggplant fruit and shoot borer (EFSB) (Leucinodes orbonalis Guenée) is a devastating lepidopteran pest of eggplant (Solanum melongena L.) in the Philippines. Management of an insect pest like the EFSB requires an understanding of its biology, evolution, and adaptations. Genomic resources provide a starting point for understanding EFSB biology, as the resources can be used for phylogenetics and population structure studies. To date, genomic resources are scarce for EFSB; thus, this study generated its complete mitochondrial genome (mitogenome). The circular mitogenome is 15,244 bp-long. It contains 37 genes, namely 13 protein-coding, 22 tRNA, and 2 rRNA genes, and has conserved noncoding regions, motifs, and gene syntenies characteristic of lepidopteran mitogenomes. Some protein-coding genes start and end with non-canonical codons. The tRNA genes exhibit a conserved cloverleaf structure, with the exception in trnS1. Partitioned phylogenetic analysis using 72 pyraloids generated highly supported maximum likelihood and Bayesian inference trees revealing expected basal splits between Crambidae and Pyralidae, and Spilomelinae and Pyraustinae. Spilomelinae was recovered to be paraphyletic, with the EFSB robustly placed before the split of Spilomelinae and Pyraustinae. Overall, the EFSB mitogenome resource will be useful for delineations within Spilomelinae and population structure analysis. Full article

The WD40 gene family is a highly conserved protein family in plants that plays a crucial role in various life activities. Although eggplant (Solanum melongena L.) genome sequencing has been completed, there is limited research on the WD40 family in eggplant, and the regulatory mechanism of its involvement in anthocyanin synthesis remains poorly understood. The research identified the eggplant WD40 gene family, comprising 187 SmWD40 members that are unevenly distributed across 12 chromosomes of the eggplant. Phylogenetic analysis classified them into 11 subgroups, with members within the same subgroup having similar motifs and gene structures. The promoter of the SmWD40 genes contains a high number of light, stress, and hormone response elements. The expression patterns of 20 SmWD40 members of the S5 subgroup were analyzed during the formation of fruit color in long purple eggplant. Subsequently, we used virus-induced gene silencing (VIGS) to confirm the significance of the TTG1 (SmWD40-56) gene in subgroup S5 for anthocyanin synthesis in eggplant fruit. To investigate the molecular mechanism of SmWD40-56 in eggplant fruit color formation, we analyzed the expression patterns of structural genes for anthocyanin synthesis in eggplant fruit silenced for SmWD40-56. Finally, we predicted the protein interaction network of the SmWD40-56 gene to understand its potential regulatory mechanisms. The result showed that SmWD40-56 may regulate the structural genes involved in anthocyanin biosynthesis and plays an important role in eggplant fruit color formation. This study provides some basis for studying the mechanism of eggplant fruit color formation. Full article

The absence of an externally-imposed 24 h light/dark cycle in closed plant production systems allows setting the light environmental parameters in unconventional ways. Innovative lighting modes for energy-saving, high-quality, and yield production are widely discussed. This study aimed to evaluate the effects of the light/dark cycles of 16/8 h (control) and 24/12 h, 48/24 h, 96/48 h, 120/60 h (unconventional cycles) based on the same total light amount, and continuous lighting (360/0 h) on plant performance of some Solanaceae species. Responses of eggplant (Solanum melongena L.), sweet pepper (Capsicum annuum L.), tobacco (Nicotiana tabacum L.), and tomato (Solanum lycopersicum L.) plants to extended light/dark cycles and continuous lighting were studied under controlled climate conditions. Plants with two true leaves were exposed to different light/dark cycles for 15 days. Light intensity was 250 µmol m⁻² s⁻¹ PPFD, provided by light-emitting diodes (LEDs). After the experiment, tomato, sweet pepper, and eggplant transplants were planted in a greenhouse and grown under identical conditions of natural photoperiod for the estimation of the after-effect of light treatments on fruit yield. Extended light/dark cycles of 24/12 h, 48/24 h, 96/48 h, 120/60 h, and 360/0 h affected growth, development, photosynthetic pigment content, anthocyanin and flavonoid content, and redox state of plants. Effects varied with plant species and length of light/dark cycles. In some cases, measured parameters improved with increasing light/dark periods despite the same total sum of illumination received by plants. Treatments of tomato and pepper transplants with 48/24 h, 96/48 h, and 120/60 h resulted in higher fruit yield compared to conventional 16/8 h photoperiod. The conclusion was made that extended light/dark cycles can result in increased light use efficiency compared to conventional photoperiod and, therefore, reduced product cost, but for practical application, the effects need to be further explored for individual plant species or even cultivars. Full article

Conventional fertilizers often result in the accumulation of chemical residues in the environment with a significant threat to ecosystems, with leaching to the groundwater disrupting the delicate balance of ecosystems. To mitigate the adverse effects of chemical residues, we need new methods and the use of eco-friendly alternatives. Cyanobacteria could play a crucial role in sustainable agriculture by reducing the partial/complete use of synthetic fertilizers. This study assessed the impacts of different concentrations of Limnospira maxima extract on the physiological aspects of Vigna unguiculata, Stevia rebaudiana, and Solanum melongena. The gas exchange parameters, chlorophyll a fluorescence, and phenotypic characteristics were measured. The net photosynthesis (A_N) of V. unguiculata, S. rebaudiana, and S. melongena increased by 23%, 40%, and 44%, respectively, upon the application of cyanobacteria extracts. Furthermore, the quantum yield of photosystem II showed that the extract application enhanced this response in the three species by 8.7%, 4.8%, and 11.3%, respectively. Similar results were found in the total plant biomass production with significant increases of 17%, 130%, and 80% with respect to the control. Moreover, a positive correlation was observed between A_N and the majority of the evaluated parameters, which could illuminate the plant’s responses to the studied treatments. The promising potential of this cyanobacteria as a biofertilizer was accentuated. Full article

Due to activities like mining and smelting, lead (Pb) enters the atmosphere in various forms in coarse and fine particles. It enters plants mainly through leaves, and goes up the food chain. In this study, PbX_n (nano-PbS, mic-PbO and PbCl₂) was applied to eggplant (Solanum melongena L.) leaves, and 379 differential metabolites were identified and analyzed in eggplant leaves using liquid chromatography–mass spectrometry. Multivariate statistical analysis revealed that all three Pb treatments significantly altered the metabolite profile. Compared with nano-PbS, mic-PbO and PbCl₂ induced more identical metabolite changes. However, the alterations in metabolites related to the TCA cycle and pyrimidine metabolism, such as succinic acid, citric acid and cytidine, were specific to PbCl₂. The number of differential metabolites induced by mic-PbO and PbCl₂ was three times that of nano-PbS, even though the amount of nano-PbS absorbed by leaves was ten times that of PbO and seven times that of PbCl₂. This suggests that the metabolic response of eggplant leaves to Pb is influenced by both concentration and form. This study enhances the current understanding of plants’ metabolic response to Pb, and demonstrates that the metabolomics map provides a more comprehensive view of a plant’s response to specific metals. Full article

Grafting techniques have been intricately associated with the optimization of water use efficiency (WUE). In this study, various eggplant (Solanum melongena L.) rootstock–scion combinations were compared under three irrigation regimes (IR): 50% deficit in water volume (IR50), a doubling of irrigation volume (IR200), and normal watering (IR100). The cultivar Black Bell (Bb) was employed as a scion, while the rootstock adopted included the F1 hybrids Energy (En) and Beaufort (Be) and one accession of S. torvum (To). The trial encompassed the evaluation of no- and self-grafted plants_. Plants grown in a cold greenhouse in Sicily were assessed for their morphological parameters, as well as their fruit production and quality. The leaf analysis encompassed the evaluation of chromatic parameters and water potential. Significant variation was observed for plant height, exhibiting the lowest values in self-grafted combinations. The leaf water potential varied significantly in relation to the rootstock–scion combination employed and to the irrigation regime. Fruit quality traits displayed significant variations for chromatic parameters L* and a*, as well as for the fruit’s longitudinal and transversal diameters and the soluble solid content. The number of fruits and fruit production per plant varied significantly in relation to the rootstock–scion combination; the highest fruit production was recorded for Black Bell grafted onto S. torvum grown by IR50. The fruit weight displayed a significant interaction between the experimental factors under study. Notably, for the WUE calculated in relation to fruit production, a significant interaction between the experimental factors studied was ascertained. The highest WUE was registered for IR50, specifically for To/Bb. This research aims to develop a comprehensive water-efficient organic farming protocol for sustainable agriculture. Full article

Fusarium wilt of Momordica charantia in the greenhouse is one of the most severe crop diseases in Shandong Province, P.R. China. This study aimed to investigate the mechanisms of accumulation and long-term survival of the pathogen in naturally pathogenic soils. Soil physicochemical properties were tested after applying a highly virulent strain of Fusarium wilt to M. charantia in an artificial disease nursery. The functional structure of soil microorganisms was analyzed through amplicon sequencing. The highly virulent strain SG−15 of F. oxysporum f. sp. momordicae was found to cause Fusarium wilt in M. charantia in Shandong Province. The strain SG−15 could not infect 14 non-host crops, including Solanum melongena and Lycopersicon esculentum, but it had varying degrees of pathogenicity towards 11 M. charantia varieties. In the artificial disease nursery for Fusarium wilt of M. charantia, the F. oxysporum was distributed in the soil to a depth of 0–40 cm and was mainly distributed in crop residues at 0–10 cm depth. During crop growth, F. oxysporum primarily grows and reproduces in susceptible host plants, rather than disease-resistant hosts and non-host crops. The colonization of the pathogen of Fusarium wilt significantly changed the soil physicochemical properties, the functional structure of soil microorganisms and the circulation of soil elements such as carbon, nitrogen, phosphorus and sulfur. Soil pH value, organic matter content, available iron content, available manganese content, FDA hydrolase activity and polyphenol oxidase activity were significantly correlated with the relative abundance of Fusarium wilt pathogens in the soil. In general, this study suggests that susceptible host plants facilitate the accumulation of Fusarium wilt pathogens in the soil. These pathogens can mediate the decomposition process of plant residues, particularly those of diseased plants, and indirectly or directly affect soil’s chemical properties. Full article

Waterlogging stress poses a significant threat to eggplants (Solanum melongena L.), causing root oxygen deficiency and subsequent plant damage. This study aims to explore the morphological changes and chlorophyll and lignin indicators of eggplant seedlings under different time points (0, 3, 6, 12, 24, 48 h) of waterlogging stress. High-throughput sequencing was used to identify differentially expressed miRNAs and mRNAs in response to waterlogging stress in eggplants. The results showed that the content of chlorophyll a significantly decreased during the early stage of waterlogging stress, while the degradation of chlorophyll b intensified with prolonged stress, and carotenoid content remained relatively stable. Additionally, this study investigated changes in root lignin, indicating its role in enhancing cell wall stability and tolerance to cope with hypoxic stress. Using DESeq2, 246 differentially expressed miRNAs were identified, among which significant changes were observed in the miR156, miR166, miR167, and miR399 families. These miRNAs may play a crucial regulatory role in eggplant’s adaptation to the hypoxic environment after waterlogging stress. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that differentially expressed genes were mainly related to cellular physiological processes, metabolic processes, and the biosynthesis of secondary metabolites, influencing the seedlings’ stress resistance under different waterlogging conditions. Furthermore, by constructing a regulatory miRNA–target gene network that pertains to eggplant’s response to waterlogging stress, we have laid the foundation for revealing the molecular mechanisms of eggplant’s response to waterlogging stress. Full article