Botrytis Cinerea Research Articles

Biocontrol Efficacy of Pseudomonas Consortia Against Botrytis Blight in Petunias.

Botrytis cinerea, a fungal pathogen causing Botrytis blight, significantly impacts greenhouse crop management due to its broad host range and infection capabilities at various growth stages. Traditional control methods, primarily reliant on fungicides, are challenged by environmental concerns and the rise of fungicide-resistant strains. This study investigates the use of beneficial Pseudomonas bacteria as a sustainable alternative. We hypothesized that specific Pseudomonas consortia could provide more effective biocontrol of B. cinerea than individual strains. Our research investigated five Pseudomonas strains (14B11, AP54, 15H3, 94G2, and 89F1) known to reduce Botrytis blight in Petunia × hybrida. Compatibility for bacterial consortia was assessed through biofilm formation and direct bacterial inhibition assays. The biocontrol effects of the bacteria against B. cinerea were investigated in vitro using shared-air space dual culture assays and in planta by inoculating detached petunia flowers. We found strain 14B11 exhibited the highest biofilm formation, with consortia of 14B11 and 89F1 showing significant enhancement compared to individual cultures, while a slight, non-significant increase was observed in 14B11 and AP54 consortia. However, strain 14B11 efficacy was inhibited by strain 15H3. Genomic analyses identified antifungal compound-related gene clusters in 14B11 and AP54, contributing to their biocontrol potential. Trials with detached flowers of Petunia × hybrida 'Carpet Red Bright' confirmed significant disease severity reduction with 14B11, AP54, and their consortia. This research highlights strategic Pseudomonas consortia as promising, eco-friendly alternatives to chemical fungicides, promoting sustainable agriculture by enhancing our understanding of how microbial interactions can be used to manage Botrytis blight.

Volatile Organic Compounds Produced by Co-Culture of Burkholderia vietnamiensis B418 with Trichoderma harzianum T11-W Exhibits Improved Antagonistic Activities against Fungal Phytopathogens.

Recently, there has been a growing interest in the biocontrol activity of volatile organic compounds (VOCs) produced by microorganisms. This study specifically focuses on the effects of VOCs produced by the co-culture of Burkholderia vietnamiensis B418 and Trichoderma harzianum T11-W for the control of two phytopathogenic fungi, Botrytis cinerea and Fusarium oxysporum f. sp. cucumerium Owen. The antagonistic activity of VOCs released in mono- and co-culture modes was evaluated by inhibition assays on a Petri dish and in detached fruit experiments, with the co-culture demonstrating significantly higher inhibitory effects on the phytopathogens on both the plates and fruits compared with the mono-cultures. Metabolomic profiles of VOCs were conducted using the solid-liquid microextraction technique, revealing 341 compounds with significant changes in their production during the co-culture. Among these compounds, linalool, dimethyl trisulfide, dimethyl disulfide, geranylacetone, 2-phenylethanol, and acetophenone were identified as having strong antagonistic activity through a standard inhibition assay. These key compounds were found to be related to the improved inhibitory effect of the B418 and T11-W co-culture. Overall, the results suggest that VOCs produced by the co-culture of B. vietnamiensis B418 and T. harzianum T11-W possess great potential in biological control.

A new species of Pythium hydnosporum as a pathogen associated with vine decline of melon (Cucumis melo L.) in Iraq

Several pathogenic fungi have become an important vine decline of cantaloupe melone (Cucumis melo L.). In 2021, root rot on cantaloupe was observed during the harvest phase in the fields in Penjwen and Shahrazoor in Sulaimani governorate of Northern Kurdistan region Iraq. This present study was conducted to isolate the causal agent of fungi in lesions of root rot of cantaloupe. A total of 16 fungal isolates were obtained of which isolates Monosporascus cannonballus, M. eutypoides, Acremonium vitellinium, Fusarium oxysporium, F. equiseti, Macrophomina phaseolina, Saccharomyces kudriavzevii, F. robinianum, Rhizopus arrhizus, Botrytis cinerea, Cytospora eucalypticola, F. falciforme, Pythium hydnosporum, Alternaria tenuissima, Rhizoctonia solani and Phytophthora colocasiae were obtained from root melon. Identification of all fungal isolates was based on using both morphological characteristics and molecular analysis, on internal transcribed spacer (ITS1, ITS4, LSU) are primers that are used for identification. DNA sequences of the fungal pathogen were identified as Pythium hydnosporum a new pathogenic fungi causal agent of cantaloupe vine decline. A pathogenicity test was conducted to verify Koch's postulates and P. hydnosporum was observed to cause root rot of melon, symptoms of the disease were similar to those seen in the field.

The Critical Role of Phenylpropanoid Biosynthesis Pathway in Lily Resistance Against Gray Mold

Gray mold caused by Botrytis elliptica is one of the most determinative factors of lily growth and has become a major threat to lily productivity. However, the nature of the lily B. elliptica interaction remains largely unknown. Here, comparative transcriptomic and metabolomic were used to investigate the defense responses of resistant (‘Sorbonne’) and susceptible (‘Tresor’) lily cultivars to B. elliptica infection at 24 hpi. In total, 1326 metabolites were identified in ‘Sorbonne’ and ‘Tresor’ after infection, including a large number of phenylpropanoids. Specifically, the accumulation of four phenylpropanes, including eriodictyol, hesperetin, ferulic acid, and sinapyl alcohol, was significantly upregulated in the B. elliptica-infected ‘Sorbonne’ compared with the infected ‘Tresor’, and these phenylpropanes could significantly inhibit B. elliptica growth. At the transcript level, higher expression levels of F3′M, COMT, and CAD led to a higher content of resistance-related phenylpropanes (eriodictyol, ferulic acid, and sinapyl alcohol) in ‘Sorbonne’ following B. elliptica infection. It can be assumed that these phenylpropanes cause the resistance difference between ‘Sorbonne’ and ‘Tresor’, and could be the potential marker metabolites for gray mold resistance in the lily. Further transcriptional regulatory network analysis suggested that members of the AP2/ERF, WRKY, Trihelix, and MADS-M-type families positively regulated the biosynthesis of resistance-related phenylpropanes. Additionally, the expression patterns of genes involved in phenylpropanoid biosynthesis were confirmed using qRT-PCR. Therefore, we speculate that the degree of gray mold resistance in the lily is closely related to the contents of phenylpropanes and the transcript levels of the genes in the phenylpropanoid biosynthesis pathway. Our results not only improve our understanding of the lily’s resistance mechanisms against B. elliptica, but also facilitate the genetic improvement of lily cultivars with gray mold resistance.

Polymorphospora lycopeni sp. nov., a lycopene-producing actinomycetes isolated from lakeside soil sample of Baiyangdian.

A novel actinomycetes producing lycopene, designated HBU208002T, was isolated from a lakeside soil sample collected in Baiyangdian, located in Xiong'an New Area of China, and its taxonomic position was investigated by a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that the strain HBU208002T fell within the genus Polymorphospora and was closely related to Polymorphospora rubra JCM 14904T (99.73% identity). However, the average nucleotide identity (ANI), digital DNA-DNA hybridization (dDDH) and average amino acid identity (AAI) values between the strain HBU208002T and P. rubra JCM 14904T were 91.78, 44.7 and 91.6%, respectively, which were lower than the ANI (95-96%), DDH (>70%) and AAI (>95%) thresholds of prokaryotic microbial defined species. The predominant fatty acids of the strain HBU208002T were iso-C16:0, C17:1 ω8c. The menaquinones of the strain HBU208002T were MK-8(H8) and MK9(H4), while those of P. rubra JCM 14904T were MK-10(H6), MK-10(H4), MK-9(H6) and MK-9(H4). Meanwhile, some phenotypic characterizations and antibacterial activities distinguished the strain HBU208002T from P. rubra JCM 14904T. The strain HBU208002T exhibited inhibitory effects on Fusarium graminearum, Fusarium verticillioides and Botrytis cinerea, but P. rubra JCM 14904T had no activity. Therefore, the strain HBU208002T should be assigned as representing a novel species of the genus Polymorphospora, for which the name Polymorphospora lycopeni was proposed. The type strain is HBU208002T (=KCTC49833T = GDMCC4.236T).

SlMYB72 interacts with SlTAGL1 to regulate the cuticle formation in tomato fruit.

The cuticle is the first physical barrier covering the surface of tomatoes and plays an important role in multiple stress responses. But the molecular regulatory networks of cuticle formation are not fully understood. In this study, we found that SlMYB72 can interact with SlTAGL1 to regulate the formation of fruit cuticle in tomato. Downregulating the expression of SlMYB72 inhibits the formation of fruit cuticle, resulting in a reduced fruit cuticle thickness, accelerated postharvest water loss, and increased susceptibility to Botrytis cinerea. RNA sequencing analysis showed that downregulation of the SlMYB72 gene decreased the expression levels of genes related to fatty acid and cuticle metabolism. SlMYB72 regulates the cuticle formation by directly binding to the promoter of long-chain acyl-coA synthetases (SlLACS1) and medium-chain alkane hydroxylase (SlMAH1). Moreover, SlMYB72 interacts with SlTAGL1, which can enhance the transcriptional activation of SlMYB72 on the SlMAH1 promoter. Overall, our study expands our understanding of the regulation of cuticle formation by SlMYB72 and provides new insights into fruit shelf life extension via manipulation of cuticle content.

Screening and stability verification of reference genes in Botrytis cinerea ZX2 fermentation

Botrytis cinerea, an airborne plant pathogen, holds the potential to synthesize sesquiterpenes, which have been used for the industrial production of abscisic acid. Previously, through our genetic technology, we obtained strain ZX2, whose main product 1´,4´-trans-ABA-diol is physiologically active in plants. In this study, 50 L of fed fermentation was carried out with ZX2 strain to study the stability of expression of TUA, TUB, ATC, EF-1, GAPDH, UCE and GTP genes. Four kinds of software (GeNorm, NormFinder, BestKeeper and Delta Ct) were used to analyze the expression stability of candidate genes, and finally the best reference gene was screened by RefFinder. Based on the results, the ACT was the most stable gene. It was used to normalize the expression levels of two genes related to 1´,4´-trans-ABA-diol production (hmgr and bcaba3) when fed-batch fermentation. Guide the selection of appropriate internal reference genes during the fermentation process to accurately quantify the relative transcription levels of target genes in B.cinerea ZX2.

Development of a high-density genetic linkage map and identification of quantitativetrait loci (QTLs) associated with Botrytis cinerea resistance in strawberry(Fragaria × ananassa Duch.)

Development of a high-density genetic linkage map and identification of quantitativetrait loci (QTLs) associated with Botrytis cinerea resistance in strawberry(Fragaria × ananassa Duch.)

Survey on the occurrence of Aspergillus section Nigri species in grapes cultivated in Umbria (central Italy) and influence of several factors on their distribution

AbstractSecondary bunch rots caused by Aspergillus species belonging to the section Nigri, commonly called black aspergilli, pose a serious threat to grapes yield and quality. Due to their ability to produce ochratoxin A (OTA), they are considered the primary source of contamination of this mycotoxin in grapes. In this study, a three-year survey was realized to assess the occurrence of black aspergilli in grapes harvested in the Umbria region, a very important grapevine cultivation area in central Italy, by fungal isolation and phylogenetic analysis. In addition, the influence of growing season, vineyard location, farming system and grapes growth stages on black aspergilli distribution was examined. Phylogenetic analysis of the 208 obtained isolates showed the presence of three black aspergilli species: Aspergillus tubingensis, Aspergillus welwitschiae and Aspergillus uvarum. Interestingly, A. carbonarius, one of the most important OTA producers, was not detected in the surveyed years. A. tubingensis, whose ability to produce OTA is controversial, was always the most isolated species followed by A. welwistichiae (OTA producer). The species A. uvarum (unable to produce OTA) was detected only in one surveyed year with a low incidence. A. tubingensis was always the species with the highest incidence, regardless of location, and farming system. Growth stage appeared to influence the incidence of the three species, that, in the case of A tubingensis, was lower during setting in comparison to berries pea-size and berries harvest-ripe. Finally, in the setting and berries pea-size stages, a stereomicroscope analysis, showed that flower debris was the substrate from which black aspergilli mainly developed prior to colonizing berries and bunches.

Design, synthesis and antifungal activity of novel pyrazole-amide-isothiazole derivatives as succinate dehydrogenase inhibitors

To discover new fungicides to protect food safety and quality, thirty-four novel pyrazole-amide-isothiazole compounds were designed, synthesised by using scaffold hopping theory for the first time. The bioactivity of all the target compounds against five plant pathogens (Including Penicillium digitatum, Physalospora piricola, Helminthosporium maydis, Sclerotinia sclerotiorum and Botrytis cinerea) were determined, the results showed that most of the compounds exhibited certain biological activities against B. cinerea in vitro. Compounds 7-XHU-6 had better antifungal activities than fluopyram with the EC50 values were 1.02, 1.78 mg/L, respectively. Moreover, the SDH inhibiting activities results indicated that 7-XHU-6 possessed outstanding activities with an IC50 value of 0.47 mg/L which better than fluopyram (IC50 = 0.88 mg/L). Besides, the in vivo experiments indicated that compound 7-XHU-6 had excellent protection efficiency and therapeutic efficiency. In addition, molecular docking studies demonstrated that compound 7-XHU-6 (−10 kcal/mol) has superior binding energy compared to fluopyram (−8.6 kcal/mol).

Association of SO2-Generating Pads before Packaging and during Cold Storage to Extend the Conservation of 'Italia' Table Grapes.

The SO2-generating pads contain different concentrations of sodium metabisulfite, which absorbs water from the grapes' transpiration, releasing SO2 gas, and there are slow-(SlowSO2) and dual (DualSO2)-releasing pads (fast release in the first 48 h and slow for up to 60 days). The ultra-fast SO2-generating pad (FieldSO2) releases the SO2 quickly for up to 6 h, and it was designed to be used soon after the harvest and until the grapes' packaging. The goal was to study the effect of FieldSO2 associated with SlowSO2 and DualSO2 pads on gray mold incidence and physicochemical and appearance characteristics of 'Italia' table grapes. Grapes were harvested from a commercial vineyard in Parana, Brazil, in 2020 and 2021, and packaged in cardboard boxes, and the treatments were as follows: control (without SO2-generating pads); FieldSO2 + SlowSO2; and FieldSO2 + DualSO2. After 30, 45, 60, 75, and 90 days of cold storage (1 ± 1 °C), the grapes were assessed for gray mold incidence, mass loss, shattered berries, stem browning, and filamentous fungi on the surface. The use of FieldSO2 associated with SO2-generating pads is effective in controlling gray mold on 'Italia' table grapes, especially the treatment FieldSO2 + DualSO2, which provides the lowest incidence of the disease up to 90 days of cold storage, while the combination with SlowSO2 results in intermediate efficacy. Treatments combining these SO2-generating pads extend the postharvest shelf life of 'Italia' grapes, with few shattered berries, low mass loss and freshness of the rachis without impairing the bunch's appearance.

An asymptomatic geminivirus activates autophagy and enhances plant defenses against diverse pathogens

Plant viral diseases cause great losses in agricultural production. Virus cross-protection is a strategy in which a mild virus is employed to shield plants against subsequent infections by severe viral strains. However, this approach is restricted to protection against the same viruses. In this study, we observed that pre-inoculation with apple geminivirus (AGV) reduced the accumulation of secondarily infected heterologous viruses, such as cucumber mosaic virus, potato virus X, and tobacco mosaic virus in Nicotiana benthamiana, tomato, and pepper plants. Transcriptional expression analysis showed that autophagy-related genes were transcriptionally up-regulated upon AGV inoculation at an early stage of infection. Accordingly, autophagic activity was observed to be elevated following AGV infection. Interestingly, AGV accumulation was reduced in autophagy-deficient plants, suggesting that autophagy activation promotes AGV infection in the plant. Moreover, pre-inoculation with AGV provided cross-protection against infection with a phytopathogenic bacterium (Pseudomonas syringae) and fungus (Botrytis cinerea) in Nicotiana species. In summary, our study showed that AGV, an asymptomatic virus, could protect plants against severe viral, fungal, and bacterial diseases to some extent through the activation of autophagy pathways, highlighting its potential as a biocontrol agent for managing a wide range of plant crop diseases in the field.

Mechanical Leaf Removal for Improved Botrytis Bunch Rot Control in Vitis vinifera 'Pinot gris' and 'Pinot noir' Grapevines in the Northeastern United States.

Late-season bunch rot can cause substantial yield loss in grapevines grown in humid regions. Fruit-zone leaf removal has been widely used to reduce bunch rot and pesticide applications through improvements in canopy microclimate and grape cluster morphology. In this study, we evaluated whether mechanical leaf removal can be a valid alternative to a labor-intensive manual application by comparing prebloom manual (PB-MA) and mechanical (PB-ME) leaf removal. We also evaluated the effects of the timing of mechanical application, prebloom (PB-ME) versus fruit set (FS-ME), on fruit traits and bunch rot, caused by Botrytis cinerea. Our trials were conducted on two Vitis vinifera 'Pinot noir' and 'Pinot gris' vineyards in the Northeastern United States over two seasons (2017 to 2018). Major findings were overall consistent between cultivars and years. Leaf removal provided reductions in fruit-zone canopy density regardless of method or timing. In general, PB-ME provided similar shifts in cluster morphological traits to PB-MA, including lower number of berries per cluster, cluster compactness, and cluster weight compared with control (no leaf removal) vines. At harvest, both prebloom leaf removal methods equally reduced Botrytis bunch rot severity, whereas Botrytis bunch rot incidence in Pinot noir was lowest for PB-ME in 1 year and PB-MA in the next year. When comparing timing of mechanical leaf removal, FS-ME provided Botrytis bunch rot reductions similar to PB-ME, without effects on cluster weight. Thus, under our growing conditions, FS-ME was considered the best mechanical leaf removal option to help manage Botrytis bunch rot without causing undesirable yield reductions.

Patulin inhibition of specific apple microbiome members uncovers Hanseniaspora uvarum as a potential biocontrol agent.

Penicillium expansum is a major postharvest pathogen of apples, causing loss in fruits through tissue damage, as well as in apple products due to contamination with the mycotoxin patulin. During infections, patulin is a cultivar-dependent virulence factor that facilitates apple lesion development. Patulin also has characterized antimicrobial activity and is important for inhibiting other competitive phytopathogens, but the role of this inhibitory activity has not been investigated in the context of the apple microbiome. In our current study, we isolated 68 apple microbiota and characterized their susceptibility to P. expansum extracts. We found Gram-negative bacteria and Basidiomycete yeast to demonstrate largely patulin-specific growth inhibition compared to Gram-positive and Ascomycete isolates. From co-cultures, we identified a Hanseniaspora and Gluconobacter pairing that reduced P. expansum biomass and found that Hanseniaspora uvarum alone is sufficient to reduce apple disease progression in vivo. We investigated possible mechanisms of H. uvarum biocontrol activity and found modest inhibition on apple puree plates, as well as a trend toward lower patulin levels at the wound site. Active biocontrol activity required live yeast, which also were effective in controlling Botrytis cinerea apple infections. Lastly, we explored the breadth of H. uvarum biocontrol activity with over 30 H. uvarum isolates and found consistent inhibition of P. expansum apple disease.

Mps1-Targeted Molecular Design of Melatonin for Broad-Spectrum Antifungal Agent Discovery.

Melatonin, a multifunctional class of natural products, has demonstrated antifungal activity, making it a promising candidate for developing antifungal agents. The mitogen-activated protein kinase (Mps1) within fungal pathogens has a target inhibitory effect of melatonin in fungi. We use a virtual screening strategy to design melatonin derivatives based on the melatonin-Mps1 targeting model. Of these, a multiflorane-substitution compound M-12 emerges as a potent antifungal agent, exhibiting broad-spectrum efficacy against eight phytopathogenic fungal species, and effectively reduces the severity of tomato gray mold, Fusarium head blight in wheat, Sclerotinia stem rot in rape, and peach brown rot. M-12 half-maximal effective concentration values (5.50 μM against Botrytis cinerea, 5.21 μM against Fusarium graminearum, 10.6 μM against Rhizoctonia solani, and 9.02 μM against Sclerotinia sclerotiorum) are better than those of commercial broad-spectrum fungicide azoxystrobin (55.0, 23.2, 46.5, and 17.7 μM, respectively). Antifungal activity of enantiomer (S)-M-12 (5.02 μM) is significantly greater than its (R)-enantiomer (23.6 μM) against B. cinerea. Molecular docking and transcriptome analysis reveal that M-12 achieves its antifungal effects by inhibiting Mps1 kinase, thereby suppressing fungal growth and virulence.

Antioxidant and Antifungal Activities and Characterization of Phenolic Compounds Using Ultra-High Performance Liquid Chromatography and Mass Spectrometry (UPLC-MS) of Aqueous Extracts and Fractions from Verbesina sphaerocephala Stems.

The Verbesina gender represents the second most diverse group from the Asteraceae family in Mexico; Verbesina sphaerocephala is one of the most distributed species along the Mexican territory. This species has been poorly studied, reporting the presence of some bioactive compounds with antioxidant and antibacterial activity. In this study, phenolic and flavonoid contents and composition, antioxidant and antifungal activities of aqueous extracts of the stem of V. sphaerocephala and its fractions were determined. The results showed that the highest antifungal activity against Botrytis cinerea was shown by the aqueous extract (IC50: 0.10 mg/mL) and the ethyl acetate fraction (IC50: 14.8 mg/mL). In addition, the aqueous extract and the ethyl acetate fraction exhibited the highest phenolic (21.40 and 21.26 mg gallic acid equivalents per gram of dry extract, respectively) and flavonoid contents (11.53 and 3.71 mg rutin equivalents, respectively) and high antioxidant activity determined by the Total Antioxidant Capacity (20.62 and 40.21 mg ascorbic acid equivalents per gram of dry extract, respectively), Ferric Reducing Power (74.76 and 129.57 mg gallic acid equivalents per gram of dry extract, respectively), DPPH (IC50: 12.38 and 7.36 mg/mL, respectively), and ABTS (IC50: 5.60 and 7.76 mg/mL, respectively) methods. Twelve phenolic compounds were detected in the aqueous extract using UPLC-MS analysis, of which the major ones were protocatechuic, vanillic, and hydroxybenzoic acid, while in the ethyl acetate fraction, the presence of 18 phenolic compounds were identified, of which the majority were vanillin, rutin, and hydroxybenzoic acid. The results of this research demonstrate that the aqueous extract of V. sphaerocephala stems has phenolic compounds with antifungal and antioxidant activity.

Leaf abaxial and adaxial surfaces differentially affect the interaction of Botrytis cinerea across several eudicots.

Eudicot plant species have leaves with two surfaces: the lower abaxial and the upper adaxial surface. Each surface varies in a diversity of components and molecular signals, resulting in potentially different degrees of resistance to pathogens. We tested how Botrytis cinerea, a necrotroph fungal pathogen, interacts with the two different leaf surfaces across 16 crop species and 20 Arabidopsis genotypes. This showed that the abaxial surface is generally more susceptible to the pathogen than the adaxial surface. In Arabidopsis, the differential lesion area between leaf surfaces was associated with jasmonic acid (JA) and salicylic acid (SA) signaling and differential induction of defense chemistry across the two surfaces. When infecting the adaxial surface, leaves mounted stronger defenses by producing more glucosinolates and camalexin defense compounds, partially explaining the differential susceptibility across surfaces. Testing a collection of 96 B.cinerea strains showed the genetic heterogeneity of growth patterns, with a few strains preferring the adaxial surface while most are more virulent on the abaxial surface. Overall, we show that leaf-Botrytis interactions are complex with host-specific, surface-specific, and strain-specific patterns.

Cyclo(Pro-Tyr) elicits conserved cellular damage in fungi by targeting the [H+]ATPase Pma1 in plasma membrane domains

Bioactive metabolites play a crucial role in shaping interactions among diverse organisms. In this study, we identified cyclo(Pro-Tyr), a metabolite produced by Bacillus velezensis, as a potent inhibitor of Botrytis cinerea and Caenorhabditis elegans, two potential cohabitant eukaryotic organisms. Based on our investigation, cyclo(Pro-Tyr) disrupts plasma membrane polarization, induces oxidative stress and increases membrane fluidity, which compromises fungal membrane integrity. These cytological and physiological changes induced by cyclo(Pro-Tyr) may be triggered by the destabilization of membrane microdomains containing the [H+]ATPase Pma1. In response to cyclo(Pro-Tyr) stress, fungal cells activate a transcriptomic and metabolomic response, which primarily involves lipid metabolism and Reactive Oxygen Species (ROS) detoxification, to mitigate membrane damage. This similar response occurs in the nematode C. elegans, indicating that cyclo(Pro-Tyr) targets eukaryotic cellular membranes.

Interactions between Weeds, Pathogen Symptoms and Winter Rapeseed Stand Structure

Rapeseed, weeds, and pathogens interact with each other. However, these interactions are not well understood. The aim of our work was to describe the relationships between weed vegetation and pathogen manifestations in rapeseed stands. Results from the four seasons show that different rapeseed stand structures produce different weed and pathogen responses. Eighteen weed species were identified in the rapeseed stands. The selected characteristics of rapeseed stands, pathogens, and weed manifestations were evaluated using redundancy analysis. Rapeseed stands with the highest levels of pathogens present (Alternaria brassiceae (Berk.) Sacc., Botrytis cinerea (De Bary) Whetzel, Sclerotinia sclerotiorum (Lib.) de Bary, Verticilium longisporum (C.Stark) Karapapa, Bainbr & Heale) had the lowest seed yield. There, the weeds Cirsium arvense (L.) Scop., Tripleurospermum inodorum (L.) Sch. Bip., Sonchus arvensis L. were more abundant in dense stands, and Phoma lingam (telomorph: Leptosphaeria maculans Ces. & De Not.) was more common. Mutual positive interactions may also include the relationship between weed species of the Asteraceae family and increased manifestations of Phoma lingam. A similar relationship can be expected for the weeds Capsella bursa-pastoris (L.) Medik., Descurainia sophia (L.) Prantl and Sclerotinia sclerotiorum symptoms.

A vacuolar invertase gene SlVI modulates sugar metabolism and postharvest fruit quality and stress resistance in tomato

Abstract Sugars act as signaling molecules to modulate various growth processes and enhance plant tolerance to various abiotic and biotic stresses. Moreover, sugars contribute to the post-harvest flavor in fleshy fruit crops. To date, the regulation of sugar metabolism and its effect in plant growth, fruit ripening, postharvest quality and stress resistance remains not fully understood. In this study, we investigated the role of tomato gene encoding a vacuolar invertase, hydrolyzing sucrose to glucose and fructose. SlVI is specifically expressed during the tomato fruit ripening process. We found that overexpression of SlVI resulted in increased leaf size and early flowering, while knockout of SlVI led to increased fruit sucrose content, enhanced fruit firmness, and elevated resistance of postharvest fruit to Botrytis cinerea. Moreover, the content of naringenin and total soluble solids was significantly increased in SlVI knockout fruit at postharvest stage. Transcriptome analysis showed a negative feedback regulation triggered by sucrose accumulation in SlVI knockout fruit resulting in a downregulation of BAM3 and AMY2, which are critical for starch degradation. Moreover, genes associated with cell wall, cutin, wax, and flavonoid biosynthesis and pathogen resistance were upregulated in SlVI knockout fruit. Conversely, the expression levels of genes involved in cell wall degradation were decreased in knockout fruit. These results are consistent with the enhanced postharvest quality and resistance. Our findings not only provide new insights into the relationship between tomato fruit sucrose content and postharvest fruit quality, but also suggest new strategies to enhance fruit quality and extend postharvest shelf life.