Search Results (29)

Planting tomatoes in enclosed facilities requires manual pollination assistance. Chemically-assisted pollination poses environmental pollution and food safety hazards. Contact vibration pollination is inefficient, ineffective, and prone to plant damage. This study developed a non-contact tomato pollination device based on pulse airflow, and conducted an experimental investigation on it. Firstly, a non-contact tomato pollination device based on pulse airflow was designed, based on the reciprocating motion of tomato flowers under the action of pulse airflow. Subsequently, this study took the coverage rate of pollen on the stigma as an indicator, and the optimal pulse airflow parameters were determined, which were a velocity of 1.22 m·s⁻¹, airflow angle of −19.69°, and pulse frequency of 25.64 Hz. Finally, comparative experiments were conducted between the pollination effect of tomatoes based on pulse airflow and other assisted pollination methods. The results show that tomato flowers produce a composite reciprocating vibration under the coupling effect of the inflorescence elastic force and the pulse airflow force, and the coverage of pollen on the stigma is 11.2% higher than assisted pollination using stable airflow. The use of a pulse airflow pollination method can increase the fruit setting rate by 13.21%, increase the weight per fruit by 11.46%, and increase the weight of fruits per bunch by 33.33%. Compared with chemically-assisted fruit setting, no chemical agents were used to ensure a fruit setting rate similar to chemical methods, and the number of seeds per fruit increased by 74.8. Compared with vibration pollination, it eliminated plant damage and increased the fruit setting rate by 4.45%, and improved efficiency by 18.6%. The results indicated that the pollination method based on pulse airflow is environmentally friendly, high-quality, and efficient. This study breaks through the theoretical and parameter limitations of traditional airflow pollination devices, and provides a theoretical base for the development of clean pollination equipment in facility agriculture. Full article

Genome editing has revolutionized plant science, providing an unprecedented ability to precisely manipulate plant genomes. For this study, genome editing was utilized to target and modify the NF-YA8 transcription factor (TF) in tomato plants (Solanum lycopersicum L. var. Heinz 1706). The primary objective of this research was to introduce targeted mutations in a non-transgenic manner to the NF-YA8 gene, which encodes the alpha subunit of the Nuclear Factor-Y (NF-Y) heterotrimeric TF, and explore its potential for developing new and improved tomato varieties. Through the transient expression of custom-engineered zinc finger nucleases (ZFNs) in tomato seeds, mutations were successfully introduced in the target gene. The recovered mutant NF-YA8 coding sequences showed a significant level of similarity to the wild type, with a range of 86.9% to 98.21%. Genotyping M2 lines revealed monogenic mutations at or near the intended target site. Phenotypic changes were also evident in both vegetative and reproductive stages of plants. The research revealed that NF-YA8 functions as a high-level regulator, orchestrating a developmental cascade that influences key agronomic traits throughout the plant’s life cycle, including cotyledon development, stem architecture, inflorescence architecture, flowering time, and fruit size and shape. Full article

Hop latent viroid (HLVd), a 256-nucleotide RNA strand with complementary base-pairing and internal stem loop structures, forms circular or rod-shaped molecules within diseased plants. RT-PCR/RT-qPCR was used to assess HLVd transmission, spread and longevity. The viroid was detected in asymptomatic stock plants and in rooted vegetative cuttings, as well as in recirculated nutrient solution sampled from propagation tables and nozzles. Plant-to-plant spread through root infection in hydroponic cultivation was demonstrated. The viroid survived for 7 days and 4 weeks, respectively, in crushed leaf extracts (sap) or dried leaves/roots at room temperature. Following stem inoculation with infectious sap, HLVd was detected in root tissues within 2–3 weeks and in the foliage within 4–6 weeks. Plants grown under a 12:12 h photoperiod to induce inflorescence development showed more rapid spread of HLVd compared to 24 h lighting. The viroid was subsequently detected in inflorescence tissues, in trichome glands, in dried cannabis flowers and in crude resinous oil extracts. Anthers and pollen from infected male plants and seeds from infected female plants contained HLVd, giving rise to up to 100% infected seedlings. Artificially inoculated tomato and tobacco plants supported viroid replication in roots and leaves. Infected cannabis leaf and root tissues treated with UV-C for 3–5 min or temperatures of 70–90 °C for 30 min contained amplifiable HLVd-RNA. Infectious plant extract treated with 5–10% bleach (0.825% NaOCl) or 1000 ppm hypochlorous acid yielded no RT-PCR bands, suggesting the RNA was degraded. Meristem tip culture from HLVd-infected plants yielded a high frequency of pathogen-free plants, depending on the genotype. Full article

Shoot determinacy is a key trait affecting productivity in tomato, quantitatively governed by genes within the flowering pathway. Achieving an optimal balance of flowering signals is essential for shaping plant architecture and maximizing yield potential. However, the genetic resources and allelic diversity available for fine-tuning this balance remain limited. In this work, we demonstrate the potential for directly manipulating shoot architecture by simultaneously targeting the flowering activating FRUITFULL(FUL)-like genes, FUL2 and MADS-BOX PROTEIN 20 (MBP20), and the flowering-repressing gene SELFPRUNING (SP). Loss of MBP20 in the sp background leads to additional inflorescences, while determinacy is largely maintained. However, additional mutation of FUL2 results in mainly indeterminate plants, which have faster sympodial cycling, leading to more compact growth and increased flower production. Our results provide a path to quantitative tuning of the flowering signals with a direct impact on shoot architecture and productivity. Full article

MADS-box transcription factors act as the crucial regulators in plant organ differentiation. Crop yields are highly influenced by the flower number and fruit growth. However, flower identification is a very complex biological process, which involves many cascade regulations. The molecular mechanisms underlying the genetic regulation of flower identification in cultivated plants, such as tomato, are intricate and require further exploration. In this study, we investigated the vital function of a SEPALLATA (SEP) MADS-box gene, SlMBP21, in tomato sympodial inflorescence meristem (SIM) development for the conversion from SIMs to floral meristems (FMs). SlMBP21 transcripts were primarily accumulated in young inflorescence meristem, flowers, sepals, and abscission zones. The Ailsa Craig (AC⁺⁺) tomato plants with suppressed SlMBP21 mRNA levels using RNAi exhibited a large increase in flower number and fruit yields in addition to enlarged sepals and inhibited abscission zone development. Scanning electron microscopy (SEM) revealed that the maturation of inflorescence meristems (IMs) was repressed in SlMBP21-RNAi lines. RNA-seq and qRT-PCR analyses showed that numerous genes related to the flower development, plant hormone signal transduction, cell cycle, and cell proliferation et al. were dramatically changed in SlMBP21-RNAi lines. Yeast two-hybrid assay exhibited that SlMBP21 can respectively interact with SlCMB1, SFT, JOINTLESS, and MC, which play key roles in inflorescence meristems or FM development. In summary, our data demonstrate that SlMBP21 functions as a key regulator in SIM development and the conversion from SIMs to FMs, through interacting with other regulatory proteins to control the expression of related genes. Full article

Tomato (Solanum lycopersicum) breeding for improved fruit quality emphasizes selecting for desirable taste and characteristics, as well as enhancing disease resistance and yield. Seed germination is the initial step in the plant life cycle and directly affects crop productivity and yield. ERECTA (ER) is a receptor-like kinase (RLK) family protein known for its involvement in diverse developmental processes. We characterized a Micro-Tom EMS mutant designated as a knock-out mutant of sler. Our research reveals that SlER plays a central role in controlling critical traits such as inflorescence development, seed number, and seed germination. The elevation in auxin levels and alterations in the expression of ABSCISIC ACID INSENSITIVE 3 (ABI3) and ABI5 in sler seeds compared to the WT indicate that SlER modulates seed germination via auxin and abscisic acid (ABA) signaling. Additionally, we detected an increase in auxin content in the sler ovary and changes in the expression of auxin synthesis genes YUCCA flavin monooxygenases 1 (YUC1), YUC4, YUC5, and YUC6 as well as auxin response genes AUXIN RESPONSE FACTOR 5 (ARF5) and ARF7, suggesting that SlER regulates fruit development via auxin signaling. Full article

Phytoplasmas are intracellular pathogenic bacteria that infect a wide range of plant species, including agriculturally important crops and ornamental trees. However, our understanding of the relationship between symptom severity, disease progression, and phytoplasma concentration remains limited due to the inability to inoculate phytoplasmas mechanically into new plant hosts. The present study investigated phytoplasma titer dynamics and symptom development in periwinkle and tomato, both infected with the same potato purple top (PPT) phytoplasma strain using a small seedling grafting approach. Virescence, phyllody, and witches’-broom (WB) symptoms sequentially developed in periwinkle, while in tomato plants, big bud (BB, a form of phyllody), cauliflower-like inflorescence (CLI), and WB appeared in order. Results from quantitative polymerase chain reaction (qPCR) targeting the PPT phytoplasma’s 16S rRNA gene revealed that in both host species, phytoplasma titers differed significantly at different infection stages. Notably, the highest phytoplasma concentration in periwinkles was observed in samples displaying phyllody symptoms, whereas in tomatoes, the titer peaked at the BB stage. Western blot analysis, utilizing an antibody specific to PPT phytoplasma, confirmed substantial phytoplasma presence in samples displaying phyllody and BB symptoms, consistent with the qPCR results. These findings challenge the conventional understanding that phytoplasma infection dynamics result in a higher titer at later stages, such as WB (excessive vegetative growth), rather than in the early stage, such as phyllody (abnormal reproductive growth). Furthermore, the PPT phytoplasma titer was markedly higher in periwinkles than in tomato plants, indicating differing susceptibilities between the hosts. This study reveals distinct host responses to PPT phytoplasma infection, providing valuable insights into phytoplasma titer dynamics and symptom development, with implications for the future management of agricultural disease. Full article

Understanding how cherry tomatoes respond to variations in greenhouse microclimate is crucial for optimizing tomato production in a controlled environment. The present study delves into the intricate relationship between summer-grown cherry tomatoes (Cheramy F1) and greenhouse conditions, exploring the influence of these conditions on growth attributes, inflorescence development, and yield potential. The aim of the study was to characterize the chronology of reproductive events, specifically flowering and fruit stages, in correlation with the prevailing greenhouse climate during the development of the first ten inflorescences on the plant. The performance of each inflorescence has been ranked based on available data, which involve a comparative analysis of both the time duration (number of days) and the frequency of yield-contributing traits, specifically the total number of flowers at the anthesis stage. The duration of each stage required for completion was recorded and presented as a productivity rate factor. Greenhouse conditions exhibited variations during the vegetative and reproductive stages, respectively, as follows: temperature - 25.1 °C and 21.33 °C, CO₂ levels - 484.85 ppm and 458.85 ppm, light intensity - 367.94 W/m² and 349.52 W/m², and humidity - 73.23% and 89.73%. The collected data conclusively demonstrated a substantial impact of greenhouse microclimate on plant growth, productivity, and inflorescence development. The development of flowers and fruit has been categorized into five stages: the fruit bud stage (FB), the anthesis stage (AS), the fruit setting stage (FS), the fruit maturation stage (FM), and the fruit ripening stage (FR). An irregular productivity and development response was noted across the first (close to roots) to the tenth inflorescence. Inflorescence 5 demonstrated the highest overall performance, followed by inflorescence numbers 4 and 6. The study findings provide valuable insights for enhancing greenhouse operations, emphasizing the improvement of both the yield and growth of cherry tomatoes while promoting environmental sustainability. A statistical analysis of variance was used to rigorously examine the presented results, conducted at a confidence level of p < 0.05. Full article

Helichrysum stoechas is a singular halophyte that has been shown to have anti-inflammatory, antioxidant, and allelopathic properties. In the work presented herein, we have characterized its inflorescences hydromethanolic extract and assessed its antifungal activity for the pre- and postharvest management of tomato crop diseases. Gas chromatography–mass spectrometry characterization of the extract showed that 4-ethenyl-1,3-benzenediol, 2,3-dihydro-benzofuran, quinic acid, 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-1-benzopyran-4-one, 1,6-anhydro-β-D-glucopyranose, catechol, scopoletin, and maltol were the main constituents. The co-occurrence of pyranones, benzenediols, and quinic acids as phytoconstituents of H. stoechas extract resulted in promising in vitro minimum inhibitory concentrations of 500, 375, 500, 187.5, 187.5, and 375 μg·mL⁻¹ against mycelia of Alternaria alternata, Colletotrichum coccodes, Fusarium oxysporum f. sp. lycopersici, Rhizoctonia solani, Sclerotinia sclerotiorum, and Verticillium dahliae, respectively. Further, to assess the potential of H. stoechas inflorescence extract for postharvest tomato crop protection, ex situ tests were conducted against C. coccodes, obtaining high protection at a dose of 750 μg·mL⁻¹. Taking into consideration that the demonstrated activity is among the highest reported to date for plant extracts and comparable to that of the synthetic fungicides tested as positive controls, H. stoechas inflorescence extract may be put forward as a promising biorational and may deserve further testing in field-scale studies. Full article

The moment at which a plant transitions to reproductive development is paramount to its life cycle and is strictly controlled by many genes. The transcription factor SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) plays a central role in this process in Arabidopsis. However, the role of SOC1 in tomato (Solanum lycopersicum) has been sparsely studied. Here, we investigated the function of four tomato SOC1 homologs in the floral transition and inflorescence development. We thoroughly characterized the SOC1-like clade throughout the Solanaceae and selected four tomato homologs that are dynamically expressed upon the floral transition. We show that of these homologs, TOMATO MADS 3 (TM3) and SISTER OF TM3 (STM3) promote the primary and sympodial transition to flowering, while MADS-BOX PROTEIN 23 (MBP23) and MBP18 hardly contribute to flowering initiation in the indeterminate cultivar Moneyberg. Protein–protein interaction assays and whole-transcriptome analysis during reproductive meristem development revealed that TM3 and STM3 interact and share many targets with FRUITFULL (FUL) homologs, including cytokinin regulators. Furthermore, we observed that mutating TM3/STM3 affects inflorescence development, but counteracts the inflorescence-branching phenotype of ful2 mbp20. Collectively, this indicates that TM3/STM3 promote the floral transition together with FUL2/MBP20, while these transcription factors have opposite functions in inflorescence development. Full article

Nowadays, increments in tomato yield seem to have reached a plateau. Tomato genebank collections have been recognized as a novel source for yield increments. The use of the diversity in Latin America for novel improved varieties is limited by the knowledge gap regarding field-grown tomatoes. As yield has complex, unresolved trade-offs, agromorphological traits become useful for further improvement. In this study, the development of successive clusters was studied in twenty-four Chilean tomato landraces to elucidate the relationships among agromorphological traits of flowers, inflorescences, and fruits. Plants yielded an average of 3297 g m⁻², with a variation coefficient of 0.44. Correlation analyses were performed to evaluate the relationships between yield components and plant phenology. Findings suggested a two-level compensation between average fresh fruit weight and the number of fruits, one on a plant basis and the second on a cluster basis. All traits evaluated had significant phenotypic correlations with yield traits. Growing degree days for a cluster to develop had a low negative phenotypic correlation with yield (−0.33***) and a high genetic correlation with the number of clusters (−0.90***). The number of set flowers, as opposed to the number of flowers, was significantly correlated with average fresh fruit weight (−0.17***), supporting the initiation of the trade-off after the fruit set. This study provides new insight into the plant agromorphology of indeterminate plants. In a global climate change context, further study of trade-off relationships is important for identifying genotypes able to sustain their productivity. Full article

Areas with saline soils are in continuous expansion, and in this context, it is very important to find solutions that help plants adapt more easily to these stress conditions, and to identify the main physiological and biochemical mechanisms involved in determining a good adaptability of plants. Biostimulants could be a plausible solution. This study was conducted in 2021 at the IULS (Iasi University of Life Sciences) in Romania, under greenhouse conditions and the biological material consisted of four tomato varieties: Buzau, Elisabeta, Bacovia, and Lillagro. For the treatments, we used natrium chloride (NaCl) 120 mM and an Atonik biostimulant. Three treatments were applied at intervals of 14 days. The Atonik biostimulant was applied by foliar spray, and the saline solution was applied to the root system. We have gathered some observations on the growth and fruiting character of the tomato plants studied: the height of the stems, the number of flowers in the inflorescence, the number of fruits, and the weight of fruits. Chlorophyll and carotenoid pigments as well as proline amino acid from leaves were also measured. Observations were made 14 days after the application of each treatment. Quantitative determinations were made 14 days after the application of the third treatment. The findings of this study made it clear that the Atonik biostimulant presented a positive effect on the physiological processes observed in tomato plants grown under salt stress conditions. Full article

The unwanted detachment of organs such as flowers, leaves, and fruits from the main body of a plant (abscission) has significant effects on agricultural practice. Both timely and precise regulation of organ abscission from a plant is crucial as it influences the agricultural yield. The tomato (Solanum lycopersicum) has become a model system for research on organ abscission. Here, we characterized four tomato natural abscission variants named jointless (j), functionally impaired jointless (fij), functionally impaired jointless like (fij like), and normal joint (NJ), based on their cellular features within the flower abscission zones (AZ). Using eight INFLORESCENCE DEFICIENT IN ABSCISSION (SlIDA) genes and eight HAESA genes (SlHAE) identified in the genome sequence of tomato, we analyzed the pattern of gene expression during flower abscission. The AZ-specific expression for three tomato abscission polygalacturonases (SlTAPGs) in the development of flower AZ, and the progression of abscission validated our natural abscission system. Compared to that of j, fij, and fij like variants, the AZ-specific expression for SlIDA, SlIDL2, SlIDL3, SlIDL4, and SlIDL5 in the NJ largely corelated and increased with the process of abscission. Of eight SlHAE genes examined, the expression for SlHSL6 and SlHSL7 were found to be AZ-specific and increased as abscission progressed in the NJ variant. Unlike the result of gene expression obtained from natural abscission system, an in silico analysis of transcriptional binding sites uncovered that SlIDA genes (SlIDA, SlIDL6, and SlIDL7) are predominantly under the control of environmental stress, while most of the SlHSL genes are affiliated with the broader context in developmental processes and stress responses. Our result presents the potential bimodal transcriptional regulation of the tomato IDA-HAE module associated with flower abscission in tomatoes. Full article

Cultivated tomato (Solanum lycopersicum) is bred for fruit production in optimized environments, in contrast to harsh environments where their ancestral relatives thrive. The process of domestication and breeding has profound impacts on the phenotypic plasticity of plant development and the stress response. Notably, the alternative splicing (AS) of precursor message RNA (pre-mRNA), which is one of the major factors contributing to transcriptome complexity, is responsive to developmental cues and environmental change. To determine a possible association between AS events and phenotypic plasticity, we investigated environment-responsive AS events in the inflorescences of cultivated tomato and its ancestral relatives S. pimpinellifolium. Despite that similar AS frequencies were detected in the cultivated tomato variety Moneymaker and two S. pimpinellifolium accessions under the same growth conditions, 528 genes including splicing factors showed differential splicing in the inflorescences of plants grown in open fields and plastic greenhouses in the Moneymaker variety. In contrast, the two S. pimpinellifolium accessions, LA1589 and LA1781, had 298 and 268 genes showing differential splicing, respectively. Moreover, seven heat responsive genes showed opposite expression patterns in response to changing growth conditions between Moneymaker and its ancestral relatives. Accordingly, there were eight differentially expressed splice variants from genes involved in heat response in Moneymaker. Our results reveal distinctive features of AS events in the inflorescences between cultivated tomato and its ancestral relatives, and show that AS regulation in response to environmental changes is genotype dependent. Full article

Non-trellised culture of tomato is gaining interest among farmers cultivating long shelf-life (LSL) landraces because of the reduction in production costs. This cropping system can benefit from the selection of determinate growth genotypes, mirroring the advancements achieved in processing tomatoes. With this aim, and profiting from the natural variation found within the Penjar landrace, we selected traditional determinate genotypes and breed novel lines carrying both the self-pruning (sp) and the compound inflorescence (s) mutations. Traditional genotypes and breeding lines were compared to commercial controls in a three multi-locality trial and under two irrigation regimes (normal watered, 100% ET_c; and water deficit, 50% ET_c). Water use efficiency, harvest index, yield and fruit quality traits were studied at harvest. During postharvest, the effects of genotype and management practices on shelf life were assessed under different storage conditions (controlled conditions/cold storage/farmer facilities). All genotypes used water more efficiently under water deficit irrigation than under normal irrigation. Harvest index was improved in the determinate genotypes and was neither affected by locality nor by irrigation factors. Breeding lines showed yields similar to the controls and the traditional ones; however, they displayed a plant architecture that facilitated their management. They also presented higher postharvest shelf life than controls and traditional lines. Shelf life was significantly affected by genotype (G), locality (L, at early stages), and irrigation regime (I, at later stages), with the contribution of the genotype to the phenotypic variance increasing along the postharvest. Low watering increased shelf life in some genotypes while cold storage and high humidity conditions impeded the long shelf-life trait. Overall, sunscald incidence and percentage of unripe fruits when using a single harvest strategy are the major limitations for non-trellised culture of Penjar tomato. In conclusion, this study sheds light on the main aspects of management and on breeding targets to promote a non-trellised culture of Penjar tomato in combination with optimal water use efficiency. Full article