Tomato Cultivars Research Articles

Role of Albitbr bio-stimulant application on growth, yield and quality characteristics of tomato (Lycopersicon esculentum) cultivars under open field conditions

Climate change coupled with the indiscriminate use of inorganic fertilizers and pesticides are causing tremendous challenges on the production potentials of crops and also health of the people of the world. As part of the sustainable production strategy, the current study was conducted at the experimental station Vniccok, Russia during summer of 2024 using a bio-stimulant “Albitbr on tomato crop. In the experiment, four different cultivars were treated with seven different doses of the bio-stimulant (control, 0.1, 0.5, 1, 2.5, 5, 10 and 50 L/ha). The highest significant leaf area (115.23 cm2) and yield of tomato fruits (83.35 t/ha) were obtained from Fenaric and Malets cultivars, respectively. Application of the bio-stimulant also resulted in a significant effect on leaf area, total yield, titratable acidity (TA) as well as total soluble solids (TSS)/TA with the highest leaf area (119.88 cm2), total yield (78.81 t/ha) being produced from the bio-stimulant dose of 2.5 L/ha, whereas the highest values of TA (0.28 %) and TSS/TA (21.72) were obtained from 0.1 L/ha and 50 L/ha, respectively.

Evaluation of Tomato (Solanum lycopersicum L.) Accessions Resistance against Fusarium Wilt (Fusarium oxysporum)

Aim: Fusarium wilt (Fusarium oxysporum) is one of the major biotic factors limiting tomato production globally. Research was conducted in three environments to screen and identify Nigeria tomato accessions that are resistant to fusarium wilt. Methodology: Twelve (12) prominent tomato accessions were collected and screened against Fusarium oxysporum by artificial inoculation under field conditions in three diverse environments. The experiments were laid out in a Randomized Complete Block Design with three replications. Data were collected on plant height (cm), number of leaves per plant, number of fruits per plant, and fresh fruits yield per plant (kg) and analyzed using IRRI STAR software. Disease scoring was done using a 0-9 point rating scale in the evaluation trials. Result: The results show some significance levels (P<0.05) in the traits studied within the accessions. The screening result revealed that none of the twelve prominent accessions is highly resistant to the pathogen. One accession was resistant. Three were moderately resistant; three were moderately susceptible and five were highly susceptible. Conclusion: The accessions that were resistant and moderately resistant could be used as a gene donor for breeding for tomato cultivars resistant to Fusarium oxysporum. Moreover, the accessions that have been identified to be resistant and moderately resistant with high yield should be cultivated before improved cultivars that will be resistant to Fusarium oxysporum will be readily available and accessible in rainforest and derived guinea savanna agro-ecological zones of Nigeria.

Genetic diversity and population structure analysis of 418 tomato cultivars based on single nucleotide polymorphism markers

IntroductionTomato (Solanum lycopersicum) is a highly valuable fruit crop. However, due to the lack of scientific and accurate variety identification methods and unified national standards, production management is scattered and non-standard, resulting in mixed varieties. This poses considerable difficulties for the cataloging and preservation of germplasm resources as well as the identification, promotion, and application of new tomato varieties.MethodsTo better understand the genetic diversity and population structure of representative tomato varieties, we collected 418 tomato varieties from the past 20 years and analyzed them using genome-wide single nucleotide polymorphism (SNP) markers. We initially assessed the population structure, genetic relationships, and genetic profiles of the 418 tomato germplasm resources utilizing simplified genome sequencing techniques. A total of 3,374,929 filtered SNPs were obtained and distributed across 12 chromosomes. Based on these SNP loci, the 418 tomatoes samples were divided into six subgroups.ResultsThe population structure and genetic relationships among existing tomato germplasm resources were determined using principal component analysis, population structure analysis, and phylogenetic tree analysis. Rigorous selection criteria identified 15 additional high-quality DNA fingerprints from 50 validated SNP loci, effectively enabling the identification of the 418 tomato varieties, which were successfully converted into KASP (Kompetitive Allele Specific PCR) markers.DiscussionThis study represents the first comprehensive investigation assessing the diversity and population structure of a large collection of tomato varieties. Overall, it marks a considerable advancement in understanding the genetic makeup of tomato populations. The results broadened our understanding of the diversity, phylogeny, and population structure of tomato germplasm resources. Furthermore, this study provides a scientific basis and reference data for future analysis of genetic diversity, species identification, property rights disputes, and molecular breeding in tomatoes.

Differential physiological and biochemical responses of two tomato cultivars to salt stress at the seedling stage

Soil salinity is a major abiotic stress that drastically hinders plant growth and development, resulting in lower crop yields and productivity. As one of the most consumed vegetables worldwide, tomato (Solanum lycropersicum L.) plays a key role in the human diet. The current study aimed to explore the differential tolerance level of two tomato varieties (Rio Grande and Agata) to salt stress. To this end, various growth, physiological and biochemical attributes were assessed after two weeks of 100 mM NaCl treatment. Obtained findings indicated that, although the effects of salt stress included noticeable reductions in shoots’ and roots’ dry weights and relative growth rate as well as total leaf area, for the both cultivars, Rio Grande performed better compared to Agata variety. Furthermore, despite the exposure to salt stress, Rio Grande was able to maintain an adequate tissue hydration and a high leaf mass per area (LMA) through the accumulation of proline. However, relative water content, LMA and proline content were noticeably decreased for Agata cultivar. Likewise, total leaf chlorophyll, soluble proteins and total carbohydrates were significantly decreased; whereas, malondialdehyde was significantly accumulated in response to salt stress for the both cultivars. Moreover, such negative effects were remarkably more pronounced for Agata relative to Rio Grande cultivar. Overall, the current study provided evidence that, at the early growth stage, Rio Grande is more tolerant to salt stress than Agata variety. Therefore, Rio Grande variety may constitute a good candidate for inclusion in tomato breeding programs for salt-tolerance and is highly recommended for tomato growers, particularly in salt-affected fields.

Response of the tomato leaf miner Phthorimaea absoluta to wild and domesticated tomato genotypes.

Phthorimaea absoluta, a highly destructive invasive pest, poses a significant threat to tomato production globally. Exploring alternative control methods, such as host plant resistance can contribute to diminish reliance on insecticides and promote sustainable integrated pest management (IPM) practices. Thus, the identification of new P. absoluta-resistant tomato cultivars and potential wild sources for breeding programmes remains imperative. We evaluated the effect of 19 tomato genotypes, comprising 16 domesticated varieties and three wild tomato species, on oviposition output of female P. absoluta, as well as on larval performance under no-choice conditions using detached leaves. We also characterized and quantified glandular and nonglandular trichomes, exploring their potential correlation with the response of P. absoluta to the tomato plants. Generally, fewer eggs were oviposited on domesticated plants, whereas the wild tomatoes Solanum arcanum and S. neorickii and the domesticated tomato Corona F1 impaired larval development. The pest larvae consumed a limited area of leaflets from S. arcanum and S. neorickii compared to other genotypes, leading to the lowest weights in both male and female pupae. All tomato plants exhibited a prevalence of nonglandular over glandular trichomes, except for S. arcanum, which exhibited a higher abundance of glandular trichomes. Although higher trichome density correlated with longer larval settlement on the leaflets, it did not influence female oviposition. Our findings demonstrate that the wild tomatoes S. arcanum and S. neorickii could be considered as potential sources for breeding programmes, and the domesticated Corona F1 could offer IPM options against P. absoluta. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The SlbHLH92 transcription factor enhances salt stress resilience by fine-tuning hydrogen sulfide biosynthesis in tomato

Ongoing soil salinization severely hampers plant growth and the sustainability of global crops production. Hydrogen sulfide (H2S), acting as a critical gaseous signaling molecule, plays a vital role in plant response to various environmental cues such as salt stress. Nonetheless, it is not well understood how the transcriptional network regulates H2S production in response to salt stress in tomato. Herein, we determine that the bHLH transcription factor SlbHLH92 functions as a transcriptional activator in tomato (Solanum lycopersicum L.), upregulating the expression of the L-CYSTEINE DESULFHYDRASE 1 (SlLCD1) gene involved in H2S biosynthesis, thereby enhancing the plants' tolerance to salt stress. When exposed to salt stress, overexpression of SlbHLH92 in tomato leads to enhanced salt tolerance compared to wild-type plants. In contrast, suppression of SlbHLH92 expression with RNAi silencing results in increased sensitivity to salt stress. Subsequent molecular and biochemical investigations confirm that the salt-induced SlbHLH92 upregulates the expression of SlLCD1, leading to an increase in H₂S levels, as well as other salt-responsive genes (SlCBL10 and SlVQ16), by directly binding to specific cis-elements in their promoter regions. Furthermore, the VQ-motif containing protein SlVQ16 physically interacts with SlbHLH92, thereby promoting an increase in its transcriptional activity. Taken together, our study reveals an emerging mechanism in which the SlbHLH92-SlVQ16-H2S signaling cascade contributes to enhancing salt tolerance in tomato, presenting potential genetic targets for breeding salt-tolerant tomato cultivars.

Photoperiodic Effect on Growth, Photosynthesis, Mineral Elements, and Metabolome of Tomato Seedlings in a Plant Factory.

The duration of light exposure is a crucial environmental factor that regulates various physiological processes in plants, with optimal timing differing between species and varieties. To assess the effect of photoperiods on the growth and metabolites of a specific truss tomato cultivar, three photoperiods (12 h, 16 h, and 20 h) were tested in a plant factory. Growth parameters, including plant height, stem diameter, fresh and dry weights of shoots and roots, photosynthetic characteristics, mineral content, and metabolome profiles, were analyzed under these conditions. The results indicated that prolonged light exposure enhanced plant growth, with the highest photosynthesis and chlorophyll content observed under a 20 h photoperiod. However, no significant correlation was observed between the photoperiod and the mineral element content, particularly for macro minerals. Metabolome analysis revealed that different photoperiods influenced the accumulation of metabolites, particularly in the lipid metabolism, amino acid metabolism, and membrane transport pathways. Long periods of light would enhance photosynthesis and metabolism, improving the rapid growth of tomato seedlings. Overall, this study provides a theoretical basis for understanding the responses of truss tomato cultivars to varying photoperiods in plant factories and proposes an optimizable method for accelerating the progress of tomato seedling cultivation.

Predicting fungal infection sensitivity of sepals in harvested tomatoes using imaging spectroscopy and partial least squares discriminant analysis

Tomatoes ( Solanum lycopersicum L.) are a widely grown and globally traded vegetable, essential for both local consumption and international trade. However, approximately 30% of harvested tomato yields are lost due to fungal decay during postharvest handling. Timely disease identification is crucial to prevent such losses, but certain tomato varieties exhibit higher susceptibility to fungal infections than others. Additionally, there are variations in susceptibility among individual sepals, with unknown underlying causes. Traditional methods for assessing fungal presence in plants have limitations, such as sample destruction and a focus on symptom detection rather than evaluating susceptibility to fungal infection. Hence, there is a demand need for an accurate, non-destructive method capable of predicting susceptibility to fungal infection. The use of hyperspectral imaging (HSI) with chemometrics presents a pioneering approach to address this need. In this study, three tomato cultivars (‘Brioso,’ ‘Cappricia,’ and ‘Provine’) were studied. Hyperspectral images were captured on day-1 of harvest, followed by controlled fungal growth conditions. Ground truth assessments were conducted by three experts on day-3 and day-4, averaging severity scores assigned per sepal. The methodology involved extracting spectra from HSI images and calibrating and validating models using partial least squares discriminant analysis (PLSDA), aiming to optimize model parameters for accurate predictions. The models were categorized into those developed using data from a single variety (intravariety) and those utilizing data from multiple varieties combined (global models). The best-performing intravariety model was established using the Cappricia variety, achieving a balanced accuracy of 0.84. Conversely, a global model combining Cappricia and Provine varieties achieved a balanced accuracy of 0.70. Overall, the results suggest that distinguishing between more and less susceptible sepals is feasible under controlled conditions.

Assessing different tomato cultivars for dehydration suitability and selection of optimum dehydration technique

Assessing different tomato cultivars for dehydration suitability and selection of optimum dehydration technique

PRP5 Induction by Infection of Pythium Sp. in Tomato

The Pseudomonas fluorescens isolate FP 7 was found to protect the tomato plants against soil borne fungus, Pythium aphanidermatum. The ability to induce defense proteins viz. -1,3 glucanase, peroxidase (PO), polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) by this P. fluorescens isolate FP 7 against P. aphanidermatum fungus was further studied. Increased activity of PO, PPO and -1,3 glucanase were observed in plants pretreated with FP 7 isolate. Native PAGE (polyacrylamide gel electrophoresis) of PO showed the single isoform in all the treatment including the control and difference is by the increased intensity of the band in the inoculated control and FP 7 treatment in the tomato plant. Isoform analysis of the PPO showed the induction of the PPO in the P. fluorescens treated plants challenged with P. aphanidermatum. -1,3 glucanase in tomato cultivar, Co 3 with and without challenge inoculation of P. aphanidermatum, revealed changes in the isoform pattern after staining the gel with 2,3,5-triphenyl tetrazolium chloride. Moreover, higher accumulation of phenolics was noticed in plants pretreated with P. fluorescens isolate FP 7 challenged with P. aphanidermatum. The relevant function of Thaumatin like defense proteins and secondary metabolites involved in the phenylpropanoid pathway collectively contributing to enhanced resistance is discussed.

Microbe-Friendly Plants Enable Beneficial Interactions with Soil Rhizosphere Bacteria by Lowering Their Defense Responses.

The use of plant growth-promoting rhizobacteria presents a promising addition to conventional mineral fertilizer use and an alternative strategy for sustainable agricultural crop production. However, genotypic variations in the plant host may result in variability of the beneficial effects from these plant-microbe interactions. This study examined growth promotion effects of commercial vegetable crop cultivars of tomato, cucumber and broccoli following application with five rhizosphere bacteria. Biochemical assays revealed that the bacterial strains used possess several nutrient acquisition traits that benefit plants, including nitrogen fixation, phosphate solubilization, biofilm formation, and indole-3-acetic acid (IAA) production. However, different host cultivars displayed genotype-specific responses from the inoculations, resulting in significant (p < 0.05) plant growth promotion in some cultivars but insignificant (p > 0.05) or no growth promotion in others. Gene expression profiling in tomato cultivars revealed that these cultivar-specific phenotypes are reflected in differential expressions of defense and nutrient acquisition genes, suggesting that plants can be categorized into "microbe-friendly" cultivars (with little or no defense responses against beneficial microbes) and "microbe-hostile" cultivars (with strong defense responses). These results validate the notion that "microbe-friendly" (positive interaction with rhizosphere microbes) should be considered an important trait in breeding programs when developing new cultivars which could result in improved crop yields.

Development of Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) in tomato genotypes

Tomato plants are the most widely cultivated fruit vegetables globally. The tomato leaf miner (Tuta absoluta) is the leading pest of this crop and can cause up to 100% loss of production. Therefore, the aim was to evaluate the development and resistance of antibiosis and non-preference types (antixenosis) for oviposition and feeding of T. absoluta in commercial tomato hybrids in choice and no-choice tests. For the experiments, an open-pollinated tomato cultivar was used as a control: ‘Santa Clara’ cultivar - susceptible - Italian type, along with eight commercial tomato hybrids were used: ‘Compack’ - salad type, ‘Caniati’ - Italian type, ‘Grazianni’ - Italian type, ‘Sweet Heaven’ - grape type, ‘Cascade’ - cherry type, ‘Ellen’ - salad type, ‘Bento’ - Italian type, and ‘Dominador’ - salad type, all having an indeterminate growth habit. According to the evaluated biological parameters (dendrogram and principal component analysis - PCA), the ‘Sweet Heaven’ hybrid showed a negative effect on the development of T. absoluta, with an increase in the duration of the larval, adult, and total phases, and low larval and total viability. The tomato hybrid ‘Cascade’ exhibited lower attractiveness for T. absoluta oviposition in no-choice tests. The tomato hybrids 'Sweet Heaven', 'Compack', and ‘Cascade’ showed a lower percentage of leaf area consumed. However, ‘Dominador’, ‘Santa Clara’, and ‘Ellen’ were the tomato genotypes that showed higher susceptibility to the development of T. absoluta, encompassing high larval, pupal, and total viability (larva-adult period). Concluding that the ‘Sweet Heaven’ hybrid negatively affected the development cycle of T. absoluta, while the ‘Cascade’ hybrid exhibited lower attractiveness for oviposition.

A host shift as the origin of tomato bacterial canker caused by Clavibacter michiganensis.

The Actinomycetota (formerly Actinobacteria) genus Clavibacter includes phytopathogens with devasting effects in several crops. Clavibacter michiganensis, the causal agent of tomato bacterial canker, is the most notorious species of the genus. Yet, its origin and natural reservoirs remain elusive, and its populations show pathogenicity profiles with unpredictable plant disease outcomes. Here, we generate and analyse a decade-long genomic dataset of Clavibacter from wild and commercial tomato cultivars, providing evolutionary insights that directed phenotypic characterization. Our phylogeny situates the last common ancestor of C. michiganensis next to Clavibacter isolates from grasses rather than to the sole strain we could isolate from wild tomatoes. Pathogenicity profiling of C. michiganensis isolates, together with C. phaseoli and C. californiensis as sister taxa and the wild tomato strain, was found to be congruent with the proposed phylogenetic relationships. We then identified gene enrichment after the evolutionary event, leading to the appearance of the C. michiganesis clade, including known pathogenicity factors but also hitherto unnoticed genes with the ability to encode adaptive traits for a pathogenic lifestyle. The holistic perspective provided by our evolutionary analyses hints towards a host shift event as the origin of C. michiganensis as a tomato pathogen and the existence of pathogenic genes that remain to be characterized.

Investigating the potency of ethylenediurea (EDU) in alleviating the affliction of ambient ozone in heat labile tomato cultivars (Solanum lycopersicum L.).

Tomato is the second most valuable vegetable crop, and its susceptibility to tropospheric ozone (O3) varies on the cultivar. Eight tomato cultivars with documented O3 sensitivity were reevaluated using ethylenediurea (400ppm EDU) to determine the effectiveness of EDU in assessing O3 sensitivity under heavily O3-polluted tropical conditions. EDU helped in amending the growth, photosynthetic pigments, photosynthetic rate, stomatal conductance, and yield characteristics in the tomato cultivars. EDU reduced the lipid peroxidation and reactive oxygen species content, while enzymatic and non-enzymatic antioxidant responses differed across cultivars. The cultivar Superbug and Sel-7 (O3 susceptible) performed better by employing more biomass and yield and exhibiting more potent antioxidative defense machinery mainly non-enzymatic antioxidants after EDU treatment. The higher value of total antioxidative potential (TAP) in O3 susceptible cultivars suggested the adaptive resilience through EDU application against O3 stress. EDU application greatly enhanced the photosynthetic rate in O3 susceptible cultivars by increasing the stomatal conductance. Hence, both biophysical and biochemical responses were involved in protection against O3 provided by EDU. Kashi chayan and VRT02 (O3 tolerant) cultivars showed least response to EDU, due to their efficient inherent mechanisms in alleviating O3 stress. Thus, EDU may be used as an efficient biomonitoring tool against O3-sensitive cultivars.

Effects of salt stress on the fruit and yield quality of some selected tomato (&lt;i&gt;Lycopersicum esculentum&lt;/i&gt; L.) varieties.

The growth, production, and nutritional characteristics of crops are impacted by abiotic factors such as salinity stress. The study aimed to assess the impact of salt stress on the fruit and yield characteristics of three distinct tomato cultivars, namely Rio, Dan syria, and UTC. Salt solutions with varying concentrations of NaCl were created by dissolving NaCl in deionized water. Four treatments were established, consisting of solutions with salt concentrations of 0g/L (control, without salt), 0.5g/L, 1.0g/L, and 1.5g/L. Each treatment was reproduced three times. The NaCl solutions were administered with a frequency of 7 days. The data in the study underwent Analysis of Variance (ANOVA). Rio outperformed the other varieties in terms of fruit quantity, fresh fruit weight, and fruit pericarp thickness under high salt stress, closely followed by UTC variety. The study also found that Dan syria performed better than the other varieties in terms of fresh and dry weight of shoot, as well as fresh weight of root, under mild and extreme salinity stress. However, Rio performed better than the other varieties in terms of dry weight of root under both mild and extreme salinity stress. The salt tolerance index of the Rio, UTC, and Dan Syria varieties under extreme salinity stress are 46.79%, 20.64%, and 34.70% respectively. This indicated that the Rio variety is the most salt-tolerant of the three types, with Dan Syria variety coming close.

Solanum pimpinellifolium exhibits complex genetic resistance to Pseudomonas syringae pv. tomato.

Pseudomonas syringae pv. tomato (Pst) is the causal agent of bacterial speck disease in tomatoes. The Pto/Prf gene cluster from Solanum pimpinellifolium was introgressed into several modern tomato cultivars and provided protection against Pst race 0 strains for many decades. However, virulent Pst race 1 strains that evade Pto-mediated immunity now predominate in tomato-growing regions worldwide. Here we report the identification of resistance to a Pst race 1 strain (Pst19) in the wild tomato accession S. pimpinellifolium LA1589 (hereafter LA1589), using our rapid high-throughput seedling screen. LA1589 supports less bacterial growth than cultivars, and does not exhibit a hypersensitive response to Pst19. We tested an existing set of 87 Inbred Backcross Lines (IBLs) derived from a cross between susceptible Solanum lycopersicum E-6203 and Solanum pimpinellifolium LA1589 for resistance to Pst19. Using single-marker analysis, we identified three genomic regions associated with resistance. Bacterial growth assays on IBLs confirmed that these regions contribute to resistance in planta. We also mapped candidate genes associated with resistance in a cross between the Solanum lycopersicum var. lycopersicum cultivar Heinz BG-1706 and S. pimpinellifolium LA1589. By comparing candidates from the two mapping approaches, we were able to identify 3 QTL and 5 candidate genes in LA1589 for a role in resistance to Pst19. This work will assist in molecular marker-assisted breeding to protect tomato from bacterial speck disease.

Brinjal (Solanum melongena) rootstocks improve photosynthetic rate, fruit yield and quality parameters in grafted tomato (Solanum lycopersicum)

The experiment was conducted during winter (rabi) seasons of 2021–22 and 2022–23 at ICAR-Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh to study the improvement in yield and quality parameters in tomato (Solanum lycopersicum L.) cultivar using brinjal (Solanum melongena L.) rootstock. Three improved cultivars of tomatoes i.e. Kashi Aman, Kashi Adarsh and Kashi Chayan were grafted over three brinjal rootstocks, IC-111056, IC- 354557, and Surya. Experimental findings revealed that brinjal rootstocks significantly affected photosynthetic traits, root architectures, fruit yields and quality traits of tomatoes. Maximum photosynthetic rate (23.8 µmol/m2/s) and stomatal conductance (492.74 mmol/m2/s) were recorded in Kashi Chayan grafted over Surya rootstock, whereas chlorophyll fluorescence yields (Fv/Fm) was significantly higher in Kashi Aman self-rooted plants (0.452–0.457). Grafting tomato onto brinjal rootstocks significantly enhanced most of the yield traits, such as fruit number, weight, size and yields. Surya + Kashi Chayan graft combination registered an enhancement in number of fruits and yields by 8.65% and 8.4%, respectively over self-rooted Kashi Chayan. Significantly higher root volumes were noticed in two graft combinations i.e. IC-354557 + Kashi Aman (28.53 cm2) and Surya + Kashi Chayan (27.98 cm2), while 63% and 44.5% higher root length density (RLD) were registered in graft combinations IC-354557 + Kashi Chayan and Surya + Kashi Chayan, respectively over self-rooted Kashi Chayan. Fruit quality such as lycopene and ascorbic acid contents were significantly affected in different rootstocks and scions, whereas fruit acidity was unaffected. From the present study it may be conclude that use of brinjal rootstock Surya significantly improved most of the physiological, yield, root architecture and fruit quality in Kashi Chayan tomato cultivars.

Assessment of Growth and Yield Characteristics of a Greenhouse Hybrid and a Dual-Purpose Tomato Cultivar under Different Microclimatic Conditions

Tomato (Solanum lycopersicum L., family Solanaceae) represents one of the most cultivated horticultural crops worldwide. It contains various nutrients, providing health benefits. For better crop management strategies, especially with global warming, it is crucial to investigate how varieties or cultivars bred for different purposes respond to the changing macro or microenvironmental conditions. This research aimed to assess the growth, reproductive development and selected quality parameters of two tomato varieties, ‘Sylviana’ (a greenhouse hybrid) and ‘Bolseno’ (a dual-purpose variety), under a greenhouse environment. The study was conducted in the mid-country wet zone of Sri Lanka where the intensive-control greenhouse (T1) maintained a favourable air temperature (&lt;33°C) for crop growth compared to high daytime temperatures of semi-intensive (T2) and less-intensive (T3) greenhouses (up to 36°C). In ‘Bolseno’, vegetative growth parameters were significantly affected (P&lt;0.05) by different environments but not in ‘Sylviana’ (P&gt;0.05). T1 resulted in the highest mean fruit weight and mean fruit diameter in both varieties. Since ‘Sylviana’ performed well in all three growing environments, the fruit quality was assessed by measuring the antioxidant activity (AOX) and total phenolic content (TPC) using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and Folin–Ciocalteu method, respectively. Significantly higher AOX (P&lt;0.05) was reported in T1 while T2 had a higher TPC. The results revealed that different tomato genotypes respond differently to changes in micro environmental conditions in terms of growth and some reproductive traits, and the same variety grown in different conditions had different TPC and AOX.

Bioprospecting Nigeria tomato cultivars against Fusarium oxysporum lycopersici under polyethylene glycol-induced drought stress

Among the vegetables, tomato is one of the economically important vegetables even at the global level. The nutritional and health benefits of tomato are so numerous to the extent that it has gained so much value in Africa due to its low-cost cultivation and contribution to livelihoods. However, Fusarium oxysporum lycopersici (FOL) and drought have been identified as potential threats to tomato production in Nigeria. To manage these challenges, one of the approaches is to identify Nigerian tomato cultivars that can exhibit resistance to FOL and drought. This study therefore investigates four Nigeria tomato cultivars; NGB00714, NGB00715, NGB00725 and NGB00740 to ascertain their resistance attributes to FOL and drought. Prior to their evaluation, Petri - dish seed germination bioassay was used in-vitro to assess the germination potentials of the tomato seeds. NGB00725 had the best germination, followed by NGB00714 and NGB00740 while the least was NGB00715. Using the Petri - dish in-vitro blotter technique, each tomato seed cultivar was separately exposed to FOL spores and FOL metabolites under drought stress induced by polyethyleneglycol (PEG-6000). Cultivar NGB00725, followed by NGB00740 exhibited resistance to FOL under PEG-induced drought stress based on their seed germination potentials. Bioprospecting resistant Nigeria tomato cultivars in this study is an indication of sustainable production of tomatoes in Nigeria against FOL under drought stress.

Evaluation of brinjal and tomato scions for enhancing yield and quality attributes in grafted brimato plants

To meet the growing demand for fresh produce in cities, promoting peri-urban and urban farming is essential to reduce reliance on rural areas for vegetables. One innovative approach developed at ICAR-IIVR, Varanasi (2019-2022), is the dual grafting of brinjal and tomato on a single brinjal plant, termed 'Brimato' (Brinjal + Tomato). Using the vigorous, waterlogging and salinity-tolerant brinjal rootstock IC 111056, four brinjal cultivars (Kashi Sandesh, Kashi Uttam, Kashi Manohar, Kashi Vijay) and three tomato cultivars (Kashi Aman, Kashi Chayan, Vani) were selected as scions. Over three years, experiments showed that scion cultivars significantly impacted Brimato productivity. Kashi Manohar combined with Kashi Aman or Kashi Chayan yielded the highest brinjal fruit numbers, while Kashi Aman combined with hybrid brinjal Kashi Sandesh resulted in the highest tomato fruit numbers. The highest fruit yields were observed with the Kashi Sandesh + Kashi Chayan combination, yielding 2.58 kg/plant. The Kashi Aman + Kashi Sandesh combination produced a cumulative yield of 5.98 kg/plant. Physiological traits like photosynthetic rate and chlorophyll fluorescence yield varied significantly among scion cultivars, with Kashi Manohar and Kashi Aman scions exhibiting the highest photosynthetic rates. Grafted Brimato plants showed enhanced fruit quality, particularly in vitamin C and β-carotene content. These findings highlight the potential of Brimato plants for urban agriculture, offering a viable solution for sustainable fresh produce supply.