Eggplant Research Articles

A Fruit-Expressed MYB Transcription Factor Regulates Anthocyanin Biosynthesis in Atropa belladonna

Anthocyanins are water-soluble flavonoid pigments that play a crucial role in plant growth and metabolism. They serve as attractants for animals by providing plants with red, blue, and purple pigments, facilitating pollination and seed dispersal. The fruits of solanaceous plants, tomato (Solanum lycopersicum) and eggplant (Solanum melongena), primarily accumulate anthocyanins in the fruit peels, while the ripe fruits of Atropa belladonna (Ab) have a dark purple flesh due to anthocyanin accumulation. In this study, an R2R3-MYB transcription factor (TF), AbMYB1, was identified through association analysis of gene expression and anthocyanin accumulation in different tissues of A. belladonna. Its role in regulating anthocyanin biosynthesis was investigated through gene overexpression and RNA interference (RNAi). Overexpression of AbMYB1 significantly enhanced the expression of anthocyanin biosynthesis genes, such as AbF3H, AbF3′5′H, AbDFR, AbANS, and Ab3GT, leading to increased anthocyanin production. Conversely, RNAi-mediated suppression of AbMYB1 resulted in decreased expression of most anthocyanin biosynthesis genes, as well as reduced anthocyanin contents in A. belladonna. Overall, AbMYB1 was identified as a fruit-expressed R2R3-MYB TF that positively regulated anthocyanin biosynthesis in A. belladonna. This study provides valuable insights into the regulation of anthocyanin biosynthesis in Solanaceae plants, laying the foundation for understanding anthocyanin accumulation especially in the whole fruits of solanaceous plants.

Productive Specialty Eggplant Cultivars Suitable for Small Farms in the Southeastern Coastal Plain

Specialty eggplants (Solanum melongena L.), cultivars with fruit shapes, sizes, and colors different from the typical teardrop-shaped, dark purple eggplant fruit, are an underproduced vegetable commodity in the southeastern United States. Seven cultivars representing seven different fruit types were grown in Charleston, SC, USA, in Spring and Fall 2018 and 2019 to assess cultivar productivity and net return. Despite year-to-year variability, Hansel (Chinese type), Millionaire (Japanese type), and Gretel (white fruit) generally had greater weights of both marketable (US Fancy and No. 1 fruit) and edible (US Fancy, No. 1 and No. 2) fruit than Fairy Tale (Sicilian type) and Patio Baby (Indian type), whereas the globe-fruited cultivars Black Beauty (heirloom) and Rosa Bianca (Italian type), had intermediate yields. Yields of plants after ratooning in the fall were lower than in the spring before ratooning. Prices per carton paid by local food hubs for US Fancy, No. 1, and No. 2 fruit were two to three times greater than wholesale terminal market prices. Nevertheless, fruit weights were a greater determinant of net returns than prices were. Growers in the southeastern coastal plain can maximize net returns from specialty eggplant crops by choosing cultivars that produce high fruit weights.

Light Environment and Photosynthetic Capacities of Leaves at Different Locations within Eggplant Canopies in a Greenhouse in Ontario, Canada

To effectively manage crop production in a greenhouse, it is essential to understand the natural light environment and physiological responses of the plants to light. This study investigated the dynamics of photosynthetic photon flux densities (PPFD) and light quality within the canopies of greenhouse-grown eggplant (Solanum melongena) and the photosynthetic capacities of leaves at different locations within the canopies. The light environment was quantified at 0.2-m intervals within (intra-canopy) and adjacent to (extra-canopy) the crop canopy on both sunny and cloudy days within a commercial greenhouse located in Leamington, Ontario, Canada. Our results indicated a linear decline in extra-canopy PPFD on both sunny and cloudy days, but an exponential decrease in intra-canopy PPFD. The intra-canopy PPFD decreased by 91% and 76% between 0 m and 0.4 m from the canopy apex on sunny and cloudy days, respectively. The lower canopy (0.6–1.2 m) light spectrum consisted largely of far-red light, equal amounts of red light and green light, with a lower percentage of blue light. Parameters derived from leaf-level light response curves indicated that the light-saturated net carbon exchange rate, light saturation point, and light compensation point decreased as the distance from canopy apex increased, whereas quantum yield was unaffected. Thus, leaves in the lower canopy were less efficient at using high PPFD, but they displayed no deterioration of photosynthetic machinery. Based solely on photosynthetic capabilities, leaves between 0 and 1.0 m from the canopy apex should not be removed to decrease the total plant sink strength.

The prospects of intercropping of brinjal (Solanum melongena L.) with other vegetables on sorjan system in vulnerable southern coastal saline and non-saline areas of Bangladesh

The prospects of intercropping of brinjal (Solanum melongena L.) with other vegetables on sorjan system in vulnerable southern coastal saline and non-saline areas of Bangladesh

Ecological intensification strategies increase abundance of denitrifying functional genes in a greenhouse agricultural soil

Understanding the denitrification process in agriculture is key to preventing nitrogen (N) losses and reducing emissions of the greenhouse gas nitrous oxide (N2O) to the atmosphere. Since the type of fertilization influences this process, in this study we evaluated the comparative effect of conventional (CON) versus ecological intensification (EI) soil management under greenhouse conditions on the abundance and expression of the denitrifying functional genes nitrite reductase (nirK, nirS) and nitrous oxide reductase (nosZ). For this purpose, quantitative PCR (qPCR) was performed in three phenological stages of eggplant (Solanum melongena L var. Telma). The results showed that the addition of organic amendments tripled the copies of nirK DNA, doubled the copies of nosZ DNA and increased the copies of nirS, albeit by 2 %, compared to conventionally managed soils. The abundance of mRNA transcripts also increased for all three genes studied: nirK increased 15-fold, followed by nirS, which tripled its expression, and nosZ, which doubled its expression. Ammonium ion (NH4-N) correlated positively with the three genes analyzed, total organic carbon (TOC) with nirK and nosZ, and pH correlated negatively with nirK and nosZ. Regardless of the type of fertilization (CON or EI), a decreasing trend in gene abundance was observed from the initial growth phase of the crop (t0) until the crop was removed and crop residues incorporated into the soil (t2). The results suggest that the dynamics and composition of the denitrifying community varied in response to the type of fertilization and the phenological stage of the crop. Further studies based on metagenomics and transcriptomics, including N2O flux measurements, are needed to better understand the denitrification process in these soils.

Microbial consortium with multifunctional attributes for the plant growth of eggplant (Solanum melongena L.).

In the past few decades, the pressure of higher food production to satisfy the demand of ever rising population has inevitably increased the use synthetic agrochemicals which have deterioration effects. Biostimulants containing beneficial microbes (single inoculants and microbial consortium) were found as an ideal substitute of synthetic chemical fertilizers. In recent years, microbial consortium is known as a better bioinoculant in comparison to single inoculant bioformulation because of multifarious plant growth-promoting advantages. Looking at the advantageous effect of consortium, in present investigation, different bacteria were isolated from rhizospheric soil and plant samples collected from the Himalayan mountains on the green slopes of the Shivaliks, Himachal Pradesh. The isolated bacteria were screened for nitrogen (N) fixation, phosphorus (P)solubilization and potassium (K) solubilization plant growth promotingattributes, and efficient strains were identified through 16S rRNA gene sequencingand BLASTn analysis. The bacteria showing a positive effect in NPK uptake were developed as bacterial consortium for the growth promotion of eggplant crop. A total of 188 rhizospheric and endophytic bacteria were sorted out, among which 13 were exhibiting nitrogenase activity, whereas 43 and 31 were exhibiting P and K solubilization traits, respectively. The selected three efficient and potential bacterial strains were identified using 16S rRNA gene sequencing as Enterobacter ludwigii EU-BEN-22 (N-fixer; 35.68 ± 00.9 nmol C2H4 per mg protein per h), Micrococcus indicus EU-BRP-6 (P-solubilizer; 201 ± 0.004 mg/L), and Pseudomonas gessardii EU-BRK-55 (K-solubilizer; 51.3 ± 1.7 mg/mL), and they were used to develop a bacterial consortium. The bacterial consortium evaluation on eggplant resulted in the improvement of growth (root/shoot length and biomass) and physiological parameters (chlorophyll, carotenoids, total soluble sugar, and phenolic content) of the plants with respect to single culture inoculation, chemical fertilizer, and untreated control. A bacterial consortium having potential to promote plant growth could be used as bioinoculant for horticulture crops growing in hilly regions.

The development of Spodoptera frugiperda (Lepidoptera: Noctuidae) on 8 major crops in Japan and its oviposition preference for maize and soybean.

The fall armyworm, Spodoptera frugiperda (J.E. Smith), is a polyphagous pest native to the Americas. It first invaded Japan in July 2019, and the most damaged crop in this region to date has been maize. To determine pest control strategies, the range of crops potentially damaged by S. frugiperda in Japan should be identified. In this study, the effects of 8 major crops in Japan-forage maize Zea mays subsp. mays, sugarcane Saccharum officinarum, forage and edible rice Oryza sativa subsp. japonica, soybean Glycine max, eggplant Solanum melongena, green bell pepper Capsicum annuum var. grossum, sweet potato Ipomoea batatas, and taro Colocasia esculenta-on the development of S. frugiperda were analyzed by feeding leaves of domestic cultivars during larval stage. Spodoptera frugiperda developed from hatching to adulthood and laid eggs in all 7 treatments, except for taro. However, among them, only soybean showed comparable developmental suitability to maize. Therefore, its oviposition preference for maize and soybean was examined using further nonchoice and choice tests. In the nonchoice test, the number of egg masses oviposited for 3 days on soybean plants was significantly less than that on test containers, while that on maize was comparable to that on containers. These findings can explain partly why major damage has been limited to maize in Japan.

Demonstration of the synergistic effect of biochar and Trichoderma harzianum on the development of Ralstonia solanacearum in eggplant

Soil degradation has been accelerated by the use of chemical pesticides and poor agricultural practices, which has had an impact on crop productivity. Recently, there has been a lot of interest in the use of eco-friendly biochar applications to enhance soil quality and sequester carbon in sustainable agriculture. This study aimed to determine the individual and combined effects of Leaf Waste Biochar (LWB) and the bio-control agent Trichoderma harzianum (BCA) on the development of bacterial wilt in eggplants (Solanum melongena) caused by Ralstonia solanacearum (RS). The effects of LWB and BCA on eggplant physiology and defense-related biochemistry were comprehensively examined. Inoculated (+RS) and un-inoculated (–RS) eggplants were grown in potting mixtures containing 3% and 6% (v/v) LWB, both with and without BCA. The percentage disease index was considerably reduced (90%) in plants grown in the 6% LWB+ BCA amended treatments. Moreover, the plants grown in LWB and inoculated with BCA had higher phenolics, flavonoids and peroxidase contents compared to the non-amended control. The level of NPK was significantly increased (92.74% N, 76.47% P, 53.73% K) in the eggplants cultivated in the 6% LWB + BCA composition. This study has shown that the association of T. harzianum with biochar improved plant growth and reduced R. solanacearum induced wilt. Furthermore, the combined impact of biochar and T. harzianum was greater in terms of wilt suppression and increase in plant physiological measurements when the biochar concentration was 6%. Biochar and bio-control agents triggered biochemical alterations, thus enhancing the management of disease-infested soils.

Iodine Fortification Study of Some Common Nigerian Vegetables Using Copper Complex

Iodine deficiency (ID) is the result of insufficient dietary iodine intake in humans, the deficiency not only leads to goiter formation but also to severe retardation of growth, development and maturation of nearly all the tissues of the body, especially those that are fast developing. The aim of this research is to evaluate levels of iodine intake by ten Nigerian vegetables using copper complex. Dry alkaline ash method was used in the determination. The results obtained showed that all the ten vegetables used absorbed high concentrations of iodine when inoculated with 0.09 M and 0.14 M [Cu(I)4]2- . Iodine phytotoxicity was observed in all the plants when inoculated with 0.2-0.8 M of the copper complex as all the plants died. Increase in the concentration of copper complex from 0.09-0.14 M increased the absorption of iodine by Amaranthus hybridus, Corchorous olitoruis, Gongronema lotifolium and Solanum melongena. The reverse was observed with Murraya koenigii, Ocimum gratissimum, Talinium triangulare, Abelmoschus esculentus, Cucurbita pepo and Telfairia occidentalis.  Ocimum gratissimum absorbed the iodine at 0.09M with value of 164.79 mg/kg, the vegetable also absorbed least at 0.14 M with a dose of 61.80 mg/kg. The intake of the iodine by the plants showed that the method can be used in the fortifying these Nigerian vegetables with iodine, thereby reducing the incidence of Iodine deficiency disorder in humans.

Investigating the influence of natural dye extracts from Ocimum gratissimum, Solanum melongena, Piper guineese, and their blend in the fabrication of perovskite solar cells

Perovskite solar cells (PSCs) represent a promising alternative to conventional silicon solar cells but face challenges like instability stemming from structural defects, environmental toxicity due to the selection of precursors and additives, and concerns regarding long-term reliability. To address these issues, we investigated the viability of cost-effective and eco-friendly PSCs by strategically incorporating natural dyes derived from indigenous plants, including Ocimum gratisimum, Solanum melongena, and Piper guineese, into the MAPbI3 perovskite crystal, using a two-step sequential drop-casting technique. The resulting perovskite films underwent comprehensive analysis for their structural, morphological, optical and elemental composition using an X-ray diffractometer (XRD), scanning electron microscopy (SEM), UV–visible spectrophotometer (UV–Vis) and energy dispersive X-ray microscopy (EDX). Performance evaluation was conducted through J-V curve analysis using a solar simulator. The XRD analysis revealed polycrystalline films with enhanced diffraction intensities corresponding to a hexagonal structure, and the UV–Vis analysis demonstrated substantial improvements in light absorption with improved optical properties. SEM studies provided crucial correlations between morphology and performance, with each sample exhibiting unique attributes, and EDX analysis confirmed essential elements within the films. The current density-voltage analysis demonstrated a 1.83 % power conversion efficiency (PCE) for the natural dye-doped device under air, surpassing the pristine device. This study advances the understanding of the synergies between natural dyes and perovskite materials, emphasizing their potential to enhance PSC efficiency. The findings underscore the considerations for designing and optimizing PSCs, paving the way for further exploration of natural dye-based approaches in sustainable photovoltaic technologies.

Preparation of Plant Growth Enhancing Bioformulation from Agricultural Wastes by Solid State Fermentation

Preparation of organic waste based bioformulation through solid state fermentation technology for application in the field offers an ecofriendly and viable alternative to sustainable food production. The present study deals with the potential of seven agrowastes as substrate carriers for the growth of indigenous strains of Pseudomonas fluorescens (Pf) and Bacillus subtilis (Bs) that stimulate plant growth. The cosubstrate (CS) with equal proportion of the seven agrowastes and both the bioinoculants (CSPfBs) proved as the best substrate carrier with highest population load of the bioinoculants at 45 days after storage (DAS). Thereafter the population declined steadily in all the bioformulations from 60 DAS to 90 DAS. However, CSPfBs gave the highest population load at 90 DAS. As individual substrate for both Pf and Bs, vermicompost performed best with a population load of 9.95 of Pf and 9.98 of Bs at 90 DAS. The bioformulations CSPfBs, VBs and VPf when applied in soil, gave the best yield in brinjal plants (Solanum melongena L. cv. Pusa Kranti) at 30 days after transplanting. Similar trends were also observed in the other yield parameters. The study indicates the scope of the prepared bioinoculant as a low cost eco friendly option for promotion of growth and yield of crops.

Assessment of Yield and Quality of Eggplant (Solanum melongena L.) Fruits Improved by Biodegradable Mulching Film in Two Different Regions of Southern Italy

Low-density polyethylene (LDPE) mulching films have an important function in crop cultivation; at the end of their life, however, their removal and disposal become both an economic and environmental problem. One possible alternative to low-density polyethylene (LDPE) mulch is provided by certified soil-biodegradable mulch films, such as those produced by Novamont and commercially available under the trade name MaterBi®. MaterBi is a biodegradable thermoplastic material made with starch and a biodegradable copolyester based on proprietary technology. In this study, we compared two biodegradable MaterBi®-based films (commercial and experimental films) with bare soil and a low-density polyethylene to evaluate their effect on yield and on a number of qualitative characteristics (organoleptic and nutraceutical composition) of eggplant fruits (cv Mirabelle F1) grown in two different regions in Southern Italy (Sicily and Campania). In our study, the use of biodegradable MaterBi® films improved not only yield and production parameters, such as the number and average weight of fruits, but also lipophilic and hydrophilic antioxidant activity and phenolic and ascorbic acid content. For many parameters, responses differed according to the cultivation environment and, in particular, the site’s pedoclimatic conditions. Our results suggest that biodegradable MaterBi®-based mulching films are a potentially valid alternative to traditional LDPEs, providing the production and quality benefits reported above and promoting environmental sustainability, thanks to their positive biodegradable properties.

Estimate of Genotypic and Phenotypic Correlation and Path Coefficient in Brinjal (Solanum melongena L)

The significant positive correlation among phenotypic and genotypic performance, as well as path correlation of crops, contributes to the selection of superior cultivars. Based on the essential relevance of these estimations, it was used in our research. The current research was carried out during autumn winter season 2021-2022 with the aim of to estimate correlation coefficient among the growth and yield attribute and to elucidate the direct and indirect effects of different traits on yield through path coefficient analysis. The experimental material for the study consisted of 40 genotypes including one check (KS-224), laid in Randomized Complete Block Design with three replications. Observations were recorded on twelve quantitative characters. The most important trait, total fruit yield per plant had exhibited highly significant and positive phenotypic correlation with average fruit weight (0.662), number of fruits per plant (0.476), fruit circumference (0.394) and fruit polar length (0.392). Average fruit weight, number of fruits per plant, fruit circumference and fruit polar length were found significantly and positively correlated among themselves. The genotypic direct and indirect effects of most of the traits were similar in nature and higher in magnitude than the phenotypic direct and indirect effect. The higher magnitude of positive direct effect on total fruit yield was exerted by average fruit weight (0.793), number of fruits per plant (0.684) and fruit circumference (0.046). While, negative direct effect on total fruit yield per plant was exerted by days to 50 per cent flowering (-0.093), calyx length (-0.052) and pedicel length (-0.022). Thus, it can be inferred from the data above that selecting for these qualities will effectively enhance the crop for increased production and contributing traits.

Studies on Genetic Variability, Heritability and Genetic Advance for Yield and Its Attributed Traits in Brinjal (Solanum melongena L.)

The genotypes of brinjal were assessed for genetic variability, heritability and genetic advance of growth and yield characters. The present investigation was carried out during rabi season of 2021 in randomized block design with three replications. The analysis of variance revealed significant variation for all the traits among the genotypes. High genotypic and phenotypic coefficient of variation was observed for the traits such as fruit weight (99.24 % and 99.27 %), number of fruits per plant (57.33 % and 57.58 %), fruit size index (54.80 % and 54.83 %), fruit length (36.54 % and 36.82 %), fruit circumference (32.16 % and 32.46 %) and fruit yield per hectare (27.26 % and 27.42 %) indicating the existence of wider variability among the genotypes for different characters. High heritability in broad sense along with high genetic advance as percent of mean was found in suggesting that these traits can be improved through direct selection due to the existence of additive gene action.

Effect of Nutrients and Phytochemical Compounds of <i>Solanum melongena</i> (Eggplants) on Cognitive Protection in Rats

Many factors among which life style and oxidative stress are implicated in the incidence of neurodegenerative diseases. One of the ways to prevent neurodegeneration is to supply the body with antioxidant molecules derived from food. The aim of this study is to evaluate the nutritional value and neuroprotective activities of eggplants on cognitive impaired rat model. Powder was made with the white and purple <i>Solanum melongena</i> and the nutritional value of each was determined. Total phenolic and flavonoid content, antioxidant activity by DPPH scavenging and reducing iron tests, were determined from aqueous, ethanolic and hydroethanolic fruit extracts. The powder and the most active extract of <i>Solanum melongena</i> were used to determine neuroprotective activity in rats. Male wistar rats were divided into 7 groups of 6 each. Morris water maze and radial maze tests were performed at the end of the experiment to assess behaviour in rats. After 28 days, the rats were sacrificed and biochemical investigations such as protein content, reduced glutathione, catalase activity, malondiadehyde and acetylcholinesterase activity were evaluated in brain homogenates. The purple <i>Solamun melongena</i> showed the highest ash (6.06%), calcium (10.50 mg/100 g of desiccated foods), phosphorus (25.75 mg/100 g of desiccated foods), potassium (218.00 mg/100 g of desiccated foods) and zinc (0.18 mg/100 g of desiccated foods) content. On the other hand, white <i>Solanum melongena</i> showed the highest fiber (3.61%) and iron (0.36 mg/100 g of desiccated foods) content. The greatest phenolic content (69.90 mg GAE /g) and flavonoid content (31.54 mg CATE / g) was observed with the purple <i>Solanum melongena</i>. It also presented the best scavenging DPPH activity (EC 50 = 41.91 μg/ml). The group Sm400 showed the best memory learning activity with radial maze tests (0.66 n/min), a significant decrease of malondialdehyde (15.26 µmole/g), acetylcholinesterase activity (0.13 nmol/min/mg protein) and an increase of protein content (43.71µmole/g) (P<0.05). The group Sm10% showed the best memory capacity radial maze tests (0.73 n/min), the lowest malondialdehyde level and acetylcholinesterase activity (12.45 µmole/g and 0.11nmol/min/mg protein respectively) (P<0.05). Purple <i>Solanum melongena</i> could be used to protect neuron functions.

Genome-Wide Identification of Glutathione S-Transferase Genes in Eggplant (Solanum melongena L.) Reveals Their Potential Role in Anthocyanin Accumulation on the Fruit Peel.

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.

Characterization of Browning, Chlorogenic Acid Content, and Polyphenol Oxidase Activity in Different Varietal Types of Eggplant (Solanum melongena) for Improving Visual and Nutritional Quality.

Eggplant (Solanum melongena L.) breeding for fruit quality has mostly focused on visual traits and nutritional and bioactive compounds, including chlorogenic acid. However, higher contents of chlorogenic acid may lead to more pronounced fruit flesh browning. We examined a diverse collection of 59 eggplant accessions across five varietal types ('black oval', 'striped', 'anthocyanin-free', 'purple', and 'black elongated') to evaluate the degree of browning, polyphenol oxidase (PPO) activity, and chlorogenic acid (CGA) content. The results reveal moderate correlations among these traits, with no clear differences among the varietal types, suggesting that other factors, including genetic variation, might significantly influence these traits. Notably, 'black oval' accessions demonstrated higher browning and PPO activity, whereas 'striped' accessions showed low variability. The identification of genotypes with lower browning and higher CGA content highlights opportunities for targeted genotype selection to improve eggplant chlorogenic acid content while maintaining low or moderate browning, pointing towards the importance of genetic considerations in breeding strategies to reduce browning and enhance nutritional value.

Comparative physiology and transcriptome response patterns in cold-tolerant and cold-sensitive varieties of Solanum melongena

BackgroundClimate change has led to severe cold events, adversely impacting global crop production. Eggplant (Solanum melongena L.), a significant economic crop, is highly susceptible to cold damage, affecting both yield and quality. Unraveling the molecular mechanisms governing cold resistance, including the identification of key genes and comprehensive transcriptional regulatory pathways, is crucial for developing new varieties with enhanced tolerance.ResultsIn this study, we conducted a comparative analysis of leaf physiological indices and transcriptome sequencing results. The orthogonal partial least squares discriminant analysis (OPLS-DA) highlighted peroxidase (POD) activity and soluble protein as crucial physiological indicators for both varieties. RNA-seq data analysis revealed that a total of 7024 and 6209 differentially expressed genes (DEGs) were identified from variety “A” and variety “B”, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of DEGs demonstrated that the significant roles of starch and sucrose metabolism, glutathione metabolism, terpenoid synthesis, and energy metabolism (sucrose and starch metabolism) were the key pathways in eggplant. Weighted gene co-expression network analysis (WGCNA) shown that the enrichment of numerous cold-responsive genes, pathways, and soluble proteins in the MEgrep60 modules. Core hub genes identified in the co-expression network included POD, membrane transporter-related gene MDR1, abscisic acid-related genes, growth factor enrichment gene DELLA, core components of the biological clock PRR7, and five transcription factors. Among these, the core transcription factor MYB demonstrated co-expression with signal transduction, plant hormone, biosynthesis, and metabolism-related genes, suggesting a pivotal role in the cold response network.ConclusionThis study integrates physiological indicators and transcriptomics to unveil the molecular mechanisms responsible for the differences in cold tolerance between the eggplant cold-tolerant variety “A” and the cold-sensitive variety “B”. These mechanisms include modulation of reactive oxygen species (ROS), elevation in osmotic carbohydrate and free proline content, and the expression of terpenoid synthesis genes. This comprehensive understanding contributes valuable insights into the molecular underpinnings of cold stress tolerance, ultimately aiding in the improvement of crop cold tolerance.

Genome-wide characterization of SmZHD gene family and the role of SmZHD12 in regulating anthocyanin biosynthesis in eggplant (Solanum melongena L.).

SmZHDs was highly expressed in anthocyanin-rich parts of eggplant. SmZHD12 can activate the expression of SmCHS, SmANS, SmDFR and SmF3H. Overexpression of SmZHD12 promotes anthocyanin biosynthesis in Arabidopsis. The Zinc finger-homeodomain (ZHD) proteins family genes are known to play a significant role in plant development and physiological processes. However, the evolutionary history and function of the ZHD gene family in eggplant remain largely unexplored. This study categorizes a total of 15 SmZHD genes into SmMIF and SmZHD subfamilies based on conserved domains. The phylogeny, gene structure, conserved motifs, promoter elements, and chromosomal locations of the SmZHD genes were comprehensively analyzed. Tissue expression profiles indicate that the majority of SmZHD genes are expressed in anthocyanin-rich areas. qRT-PCR assays revealed distinct expression patterns of SmZHD genes in response to various treatments, indicating their potential involvement in multiple signaling pathways. Analysis of transcriptomic data from light-treated eggplant peel identified SmZHD12 as the most light-responsive gene among the 15 SmZHD genes. Consequently, this study provides further evidence that SmZHD12 facilitates anthocyanin accumulation in Arabidopsis leaves by upregulating the expression of anthocyanin biosynthesis structural genes, as confirmed by dual-luciferase assays and Arabidopsis genetic transformation. Our study will lay a solid foundation for the in-depth study of the involvement of SmZHD genes in the regulation of anthocyanin biosynthesis.

Impact of Micronutrients and Plant Growth Regulators on Brinjal (Solanum melongena L.) Growth, Yield and Quality

The present research work conducted to find out the effect of plant growth regulators and micronutrients on growth, yield, and quality of Brinjal (Solanum melongena L.) under open field condition. The experiment was designed in a Randomized Complete Block Design (RCBD) with three replicates. The experiment was conducted on Horticulture farm at Sher-e-Bangla Agricultural University; Dhaka, Bangladesh from July 2022 to June 2023. The experimental treatments included three levels of PGR i.e. No PGR, 200 ppm gibberellic acid (GA3) and 100 ppm Naphthaleneacetic acid (NAA) and three levels of micronutrients i.e.no micronutrients, 200 ppm Boron and 200 ppm Zn. The treatments had a substantial effect on growth, yield, and quality of Brinjal. GA3 treated plants performed better than NAA and no PGR treated plants and Zn produced higher yields and quality than Boron and no micronutrients treated plants in most of the parameters. Considering treatment combination of PGR and micronutrients, plant height, leaf area (471.33 cm2), SPAD value (52.95), number of flowers plant-1 (65.33), number of fruits plant-1 (58.38), yield plant-1  (3312.8g), lipid (0.35%) were observed highest from the treatment combination of 200 ppm GA3 with 200 ppm Zinc whereas dry weight of whole plant (158.80 g), individual fruit weight (67.33g) and  fiber (12.28%) were observed from the treatment combination of 100 ppm NAA with 200 ppm zinc but in case of number of branch (14.00) and Ash (8.44%) were observed  from the treatment of 100 ppm NAA application . Maximum parameter showed lowest value under no treatment combination. This study suggests that foliar application of GA3 with micronutrients such as Zinc during flowering stage of eggplant is the most effective strategy for improving the nutritional quality of Brinjal fruits and increasing crop yields, both of which will help to reduce micronutrient malnutrition and hunger worldwide.