Strawberry Leaf Research Articles

Hyperspectral Imaging Combined with Deep Learning for the Early Detection of Strawberry Leaf Gray Mold Disease

The presence of gray mold can seriously affect the yield and quality of strawberries. Due to their susceptibility and the rapid spread of this disease, it is important to develop early, accurate, rapid, and non-destructive disease identification strategies. In this study, the early detection of strawberry leaf diseases was performed using hyperspectral imaging combining multi-dimensional features like spectral fingerprints and vegetation indices. Firstly, hyperspectral images of healthy and early affected leaves (24 h) were acquired using a hyperspectral imaging system. Then, spectral reflectance (616) and vegetation index (40) were extracted. Next, the CARS algorithm was used to extract spectral fingerprint features (17). Pearson correlation analysis combined with the SPA method was used to select five significant vegetation indices. Finally, we used five deep learning methods (LSTMs, CNNs, BPFs, and KNNs) to build disease detection models for strawberries based on individual and fusion characteristics. The results showed that the accuracy of the recognition model based on fused features ranged from 88.9% to 96.6%. The CNN recognition model based on fused features performed best, with a recognition accuracy of 96.6%. Overall, the fused feature-based model can reduce the dimensionality of the classification data and effectively improve the predicting accuracy and precision of the classification algorithm.

Characterization of Superoxide Dismutase (SOD) Gene Family and Their Responses to Salinity Stress and Fruit Development in Octoploid Strawberry

Superoxide dismutases (SODs), as the first line of defense against reactive oxygen species (ROS), play an essential role in protecting plants from adverse elicitors during plant growth and development. However, little is known about the SOD gene family and their response to salinity stress and fruit development in cultivated strawberries (Fragaria × ananassa). In this study, 32 SOD genes consisting of 16 Cu/ZnSODs, 11 FeSODs, and 5 MnSOD were identified, which presented three well-resolved clades in the phylogenetic tree. Each clade had similar motifs, and exon–intron structures, which in turn supported the evolutionary classification. Cis-acting element analysis suggested that FaSOD genes might be involved in the plant response to abiotic and biotic stresses, hormones, and light. The analysis of previously published transcriptome data revealed that FaSOD genes are expressed variably under salt stress. Among these SODs, FaMSD5 was expressed at relatively high levels in strawberry root and leaf, and its transcript abundance significantly increased after salt treatment. Some transcription factors related to photomorphogenesis, hormone signaling pathways, and hyperosmotic salinity response were predicted to bind to the FaMSD5 promoter. These outcomes implied that FaMSD5 might play an important role in protection against salt stress. In addition, the comprehensive transcriptome analysis of FaSOD genes in strawberry fruit showed that almost all FaCSDs and FaMSDs were more highly expressed than FaFSDs at different developmental stages, and the expression patterns of FaCSD1, FaCSD2, FaCSD7, FaCSD8, and FaCSD10 suggested that they were likely to be involved in fruit development and ripening. This study provides a basis for further exploration of the function of the FaSOD gene family in strawberry and provides candidate FaSOD genes for enhancing salinity tolerance and regulating fruit development and ripening.

Automatic Disease Detection from Strawberry Leaf Based on Improved YOLOv8.

Strawberries are susceptible to various diseases during their growth, and leaves may show signs of diseases as a response. Given that these diseases generate yield loss and compromise the quality of strawberries, timely detection is imperative. To automatically identify diseases in strawberry leaves, a KTD-YOLOv8 model is introduced to enhance both accuracy and speed. The KernelWarehouse convolution is employed to replace the traditional component in the backbone of the YOLOv8 to reduce the computational complexity. In addition, the Triplet Attention mechanism is added to fully extract and fuse multi-scale features. Furthermore, a parameter-sharing diverse branch block (DBB) sharing head is constructed to improve the model's target processing ability at different spatial scales and increase its accuracy without adding too much calculation. The experimental results show that, compared with the original YOLOv8, the proposed KTD-YOLOv8 increases the average accuracy by 2.8% and reduces the floating-point calculation by 38.5%. It provides a new option to guide the intelligent plant monitoring system and precision pesticide spraying system during the growth of strawberry plants.

Effects of Strawberry Tree (Arbutus unedo L.) Aqueous Leaf Extract and Arbutin on PK-15 and HepG2 Cells.

The antioxidant properties of the leaves of the Mediterranean strawberry tree (Arbutus unedo L.) are mainly attributed to the main bioactive compound, the phenolic glycoside arbutin. In this study, the safety profile of strawberry tree aqueous leaf extract (STE) and arbutin at the DNA level was assessed in vitro using porcine PK-15 kidney cells and HepG2 cells derived from human hepatomas. To examine the effects on cell viability and DNA damage, cells were treated for 24 h with STE or arbutin at three concentrations presumed to be non-toxic (400, 200, and 11.4 µg/mL). Assessments were performed using the MTS viability assay, dual acridine orange/ethidium bromide fluorescent staining, and alkaline comet assay. Results showed that the highest concentration (400 µg/mL) of both tested compounds had no significant cytotoxic effects on either PK-15 or HepG2 cells. Apoptosis was the predominant type of cell death and the total amount of DNA damage in treated cells was within acceptable limits. These results on the in vitro cytocompatibility of arbutin and STE with PK-15 and HepG2 cells could serve to make more reliable judgements about safe levels of arbutin in cosmetic products and functional foods, given the increased popularity of the compound in recent years.

Effects of Strawberry Tree Water Leaf Extract and Arbutin on Biochemical Markers and DNA Integrity in Brain Cells of Lewis Rats.

There is growing evidence that arbutin and plant extracts rich in arbutin, such as extracts of the strawberry tree (Arbutus unedo L.), exert a range of beneficial effects, including cyto- and genoprotective properties. This study evaluated the effects of strawberry tree water leaf extract (STE) and arbutin in the brain tissue of Lewis rats. STE or arbutin were administered per os to male and female rats at a dose of 200 mg/kg body weight/day for 14 or 28 days. Treatment outcomes were evaluated using biochemical markers (lipid peroxidation and the activities of the antioxidative enzymes catalase and superoxide dismutase). The effects of the tested substances on DNA integrity in brain cells were evaluated using the alkaline comet assay. The results suggest a high biocompatibility of both tested substances with rat brain tissue. No significant harmful disturbances were observed in the oxidative/antioxidative status or impairments of DNA integrity in the rat brain cells. Nearly all post-treatment values were within tolerable limits as compared to the matched control rats. Such encouraging findings support further research using other subtle biomarkers to clarify the safety aspects of arbutin and STE prior to the development of specific nutraceutical products.

UVC (254 nm) and Far UVC (222 nm) Irradiation Affects In Vitro Growth of Colletotrichum sp. Isolates and Their Infection of Detached Strawberry Leaves

Conventional ultraviolet C at 254 nm (UVC) and Far UVC at 222 nm (Far UVC) were evaluated as alternatives to fungicides for disease control. Conidia of 13 isolates of strawberry anthracnose pathogens (five Colletotrichum species in two complexes: C. acutatum and C. gloeosporioides) were uniformly dispersed onto agar and irradiated with UVC and Far UVC doses ranging from 52 to 1,248 J·m−2. After 48 h of incubation, a UVC dose of 1,248 J·m−2 and Far UVC doses from 234 to 935 J·m−2 reduced Colletotrichum colony counts to <10 colonies/Petri dish. Cultures exposed to UVC light followed by 4 h of darkness had lower colony counts than cultures incubated under continuous light. This dark incubation period was not required for Far UVC to obtain optimal lethality, indicating Far UVC irradiation can be applied during the day or night and achieve similar fungal lethality. Inoculation of detached leaves of three anthracnose-susceptible strawberry cultivars with conidial suspensions of Colletotrichum spp. revealed that UV irradiation can affect development of anthracnose symptoms. Leaves receiving UVC doses of 312 and 624 J·m−2 or a Far UVC dose of 467 J·m−2 reduced anthracnose infection with little or no plant injury. A UVC dose of 1,248 J·m−2 and Far UVC doses ≥ 467 J·m−2 inflicted varying degrees of plant injury. Disease control intended to reduce the number of fungicidal applications could be developed with moderate doses of UVC and Far UVC irradiation while slowing the evolution of pesticide-resistant strains. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 “No Rights Reserved” license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.

Plant metabolic responses to soil herbicide residues differ under herbivory in two woodland strawberry genotypes

The use of glyphosate-based herbicides (GBHs) to control weeds has increased exponentially in recent decades, and their residues and degradation products have been found in soils across the globe. GBH residues in soil have been shown to affect plant physiology and specialised metabolite biosynthesis, which, in turn, may impact plant resistance to biotic stressors.In a greenhouse study, we investigated the interactive effects between soil GBH residues and herbivory on the performance, phytohormone concentrations, phenolic compound concentrations and volatile organic compound (VOC) emissions of two woodland strawberry (Fragaria vesca) genotypes, which were classified as herbivore resistant and herbivore susceptible. Plants were subjected to herbivory by strawberry leaf beetle (Galerucella tenella) larvae, and to GBH residues by growing in soil collected from a field site with GBH treatments twice a year over the past eight years.Soil GBH residues reduced the belowground biomass of the susceptible genotype and the aboveground biomass of both woodland strawberry genotypes. Herbivory increased the belowground biomass of the resistant genotype and the root–shoot ratio of both genotypes. At the metabolite level, herbivory induced the emission of several VOCs. Jasmonic acid, abscisic acid and auxin concentrations were induced by herbivory, in contrast to salicylic acid, which was only induced by herbivory in combination with soil GBH residues in the resistant genotype. The concentrations of phenolic compounds were higher in the resistant genotype compared to the susceptible genotype and were induced by soil GBH residues in the resistant genotype.Our results indicate that soil GBH residues can differentially affect plant performance, phytohormone concentrations and phenolic compound concentrations under herbivore attack, in a genotype-dependent manner. Soil GBH altered plant responses to herbivory, which may impact plant resistance traits and species interactions. With ongoing agrochemical pollution, we need to consider plant cultivars with better resistance to polluted soils while maintaining plant resilience under challenging environmental conditions.

First report of the new Neopestalotiopsis species causing strawberry leaf spot and fruit rot in Georgia.

In April 2023, symptomatic strawberry (Fragaria × ananassa) plants (cv. 'Camarosa' and 'Florida Brilliance') were observed at a commercial farm in Worth County, GA (USA). Symptoms included foliar, irregularly distributed, and different-sized spots (dark brown with light brown centers) and dark brown V-shaped necrotic areas starting at the leaf edge. By the time of sample collection, ~50% incidence was reported in the field. Leaf samples were collected and shipped overnight to the laboratory. Black acervuli were observed readily on old necrotic foliar lesions. Conidial morphology was consistent with that observed with Neopestalotiopsis species (Maharachchikumbura et al. 2014). Conidia were ellipsoid to fusiform, five-celled, with three light brown median cells and one hyaline apical and basal cell. Apical cells had two-to-four flexuous appendages, and the basal cell had one non-flexuous appendage (Fig 1). The average (n = 20) conidia length, not including the appendages, was 26.6 µm (SD: 2.8), and width was 6.3 µm (SD: 0.94). Fungal isolation was conducted on acidified PDA and incubated at 25°C for 6 days. Dense, white mycelia were observed on the upper plate surface, while a pale pink/orange coloration was observed on the underside (Fig 1). Black acervuli formed on the surface of the white mycelial mat. Six isolates were purified and selected to confirm the species identity. DNA was extracted from 6-day-old cultures and PCR was conducted following Kaur et al. (2023). Amplified DNA was digested with the restriction enzyme BsaWI and two bands were clearly visualized (~130 and ~290 bp), along with a faint band of 20-bp (Fig 2). Four of the six isolates were selected for sequencing of the β-tubulin gene. BLAST queries using the consensus sequence showed that all isolates had 100% identity to strain N21002 from Florida (FL), characterized as Neopestalotiopsis sp. (Kaur et al. 2023). One representative isolate (AJ07-2023) was deposited in GenBank (accession No. PP316103). Pathogenicity tests were performed on 27-day-old transplants of Sensation 'Florida127' provided by Natalia Peres from the UF. Plants were grown in 10.5 cm pots in the greenhouse. Isolate AJ07-2023 was grown on PDA for 30 days at 25°C, and the spore suspension was adjusted at 106 spore/ml. Five strawberry plants were sprayed with 5 ml of inoculum using a Preval sprayer with a CO2 canister, and 5 plants were sprayed with sterile distilled water. Plants were placed in a growth chamber for 6 days and covered with plastic bags after the sixth day to maintain ~85% relative humidity and 25°C. Foliar symptoms, including dark-brown circular lesions occurring towards the edge of leaves with light-brown center and light-yellow halo, developed 13 days after inoculation. No symptoms were observed on control plants. Neopestalotiopsis sp. was reisolated from inoculated plants as described above. Colony, conidial morphology, and PCR results were consistent with the original isolates. Neopestalotiopsis disease has been reported on strawberry in FL (Baggio et al. 2021), OH (Rotondo et al. 2022) and IN (Guan et al. 2023). Although the disease has been observed sporadically in GA since 2020 (Brannen, personal communication), to our knowledge, this is the first official report of the new Neopestalotiopsis sp. in GA. It has been reported that this new strain is more aggressive on fruits and leaves than other Neopestalotiopsis spp. (Baggio et al. 2021), therefore, accurate identification is critical for proper management.

Efficacy of Using Chemical Inducers and Biological Agents to Control Strawberry Leaf Spot Disease on Chemical Components and Enzyme Activity

Strawberry plants are subjected to many pathogens. Fungal diseases of strawberries are important worldwide and occur in all parts of the plant, including leaves, crowns, and fruits. The results of the bio-agent experiment indicated that Trichoderma harzianum was the most effective in reducing the growth of Alternaria alternata and Botrytis cinerea in vitro, the main causes of leaf spots in strawberry plants. The inhibition zone was observed and mycelium of T. harzianum invaded the colony of the tested pathogens. The importance of the biochemical study of defense reaction in the physiology of disease resistance was accepted. The activity of total, free, and conjugated phenols as well as peroxidase, polyphenol oxidase, and catalase enzyme activities were determined in resistant and susceptible strawberry cultivars. All the total, free, and conjugated phenols increased in resistant cultivars (Fortuna and Winter Star) and decreased in susceptible cultivar (Festival). Oxidative enzymes, like the increased activity of enzymes that appear mince of new polypeptide protein, have become models in the study of plant disease resistance. The higher content of peroxidase, polyphenol oxidase, and catalase enzymes in resistant cultivars, were noticed compared with those in susceptible ones. It was found also that, the chemical inducers increased total phenols in resistant and susceptible cultivars i.e., potassium di-phosphate, ferrous sulphate, and oxalic acid. Inducer resistance also caused an increase of free phenols than the control. However, conjugated phenols accumulated faster after using chemical inducers in the leaves of the resistant cultivars, than the susceptible ones.

Morphological and Molecular Analysis of Two Mycophagous Nematodes, Aphelenchoides bicaudatus and A. rutgersi (Nematoda: Aphelenchoididae) from Florida Strawberry.

From 2016 to 2021, nematode surveys in Florida strawberry fields revealed several species of foliar nematodes (Aphelenchoides spp.). Aphelenchoides besseyi sensu stricto was detected only in 2016 and 2017 on photosynthetic strawberry leaves/buds, but other not well characterized populations of Aphelenchoides sp. were found on declining/dessicated leaves. Morphological analyses showed that these samples of Aphelenchoides sp. consisted of A. bicaudatus, a species detected in Florida for the first time, and A. rutgersi, a species previously reported in Florida from the citrus rhizosphere. These two species differed from A. besseyi in the shape of their tail terminus: bifurcate in A. bicaudatus; mucronate with a ventral thin mucro in A. rutgersi; and stellate in A. besseyi. One population each of these species was used for morphological and molecular analyses after being reared on Monilinia fructicola. Body and tail length differences were observed among Florida A. bicaudatus and other populations from the Far East and South Africa. Phylogenetic analyses of the rRNA gene sequences showed that Florida A. bicaudatus grouped with those of species from South Korea, Taiwan, and the Netherlands and several other populations listed as Aphelenchoides sp. from Brazil, Costa Rica, and Japan, which were considered as representatives of A. bicaudatus in this study. Similarly, sequences of Florida A. rutgersi grouped with those from environmental samples in Japan and North Carolina, which were listed as Aphelenchoides sp. and were considered as representatives of A. rutgersi in this study. Photosynthetic strawberry leaf samples were free from both A. bicaudatus and A. rutgersi, indicating that these two species did not damage strawberry. They were associated with desiccated leaves and/or propagative stolons, usually infected by fungi, confirming that they are mycetophagous under field conditions in this study. Results of soybean leaf inoculation on moist filter paper containing A. bicaudatus specimens showed that this species could become phytophagous under artificial conditions. Nematodes penetrated the leaf epidermis and migrated into the mesophyll causing leaf tissue discoloration/necrosis, which remained localized within the infested area. Soybean leaf damage was almost negligible, and no nematode reproduction was observed in the inoculated soybean areas.

Changes in Phytohormones and Transcriptomic Reprogramming in Strawberry Leaves under Different Light Qualities.

Strawberry plants require light for growth, but the frequent occurrence of low-light weather in winter can lead to a decrease in the photosynthetic rate (Pn) of strawberry plants. Light-emitting diode (LED) systems could be used to increase Pn. However, the changes in the phytohormones and transcriptomic reprogramming in strawberry leaves under different light qualities are still unclear. In this study, we treated strawberry plants with sunlight, sunlight covered with a 50% sunshade net, no light, blue light (460 nm), red light (660 nm), and a 50% red/50% blue LED light combination for 3 days and 7 days. Our results revealed that the light quality has an effect on the contents of Chl a and Chl b, the minimal fluorescence (F0), and the Pn of strawberry plants. The light quality also affected the contents of abscisic acid (ABA), auxin (IAA), trans-zeatin-riboside (tZ), jasmonic acid (JA), and salicylic acid (SA). RNA sequencing (RNA-seq) revealed that differentially expressed genes (DEGs) are significantly enriched in photosynthesis antenna proteins, photosynthesis, carbon fixation in photosynthetic organisms, porphyrin and chlorophyll metabolisms, carotenoid biosynthesis, tryptophan metabolism, phenylalanine metabolism, zeatin biosynthesis, and linolenic acid metabolism. We then selected the key DEGs based on the results of a weighted gene co-expression network analysis (WGCNA) and drew nine metabolic heatmaps and protein-protein interaction networks to map light regulation.

A novel transcription factor FnMYB4 regulates pigments metabolism of yellow leaf mutants in Fragaria nilgerrensis

The strawberry species Fragaria nilgerrensis Schlechtendal ex J. Gay, renowned for its distinctive white, fragrant peach-like fruits and strong disease resistance, is an exceptional research material. In a previous study, an ethyl methane sulfonate (EMS) mutant library was established for this species, resulting in various yellow leaf mutants. Leaf yellowing materials are not only the ideal materials for basic studies on photosynthesis mechanism, chloroplast development, and molecular regulation of various pigments, but also have important utilization value in ornamental plants breeding. The present study focused on four distinct yellow leaf mutants: mottled yellow leaf (MO), yellow green leaf (YG), light green leaf (LG), and buddha light leaf (BU). The results revealed that the flavonoid content and carotenoid-to-chlorophyll ratio exhibited a significant increase among these mutants, while experiencing a significant decrease in chlorophyll and carotenoid contents compared to the wild type (WT). To clarify the regulatory mechanisms and network relationships underlying these mutants, the RNA-seq and weighted gene co-expression network (WGCNA) analyses were employed. The results showed flavonoid metabolism pathway was enriched both in MO and YG mutants, while the chlorophyll biosynthesis pathway and carotenoid degradation pathway were only enriched in MO and YG mutants, respectively. Subsequently, key structural genes and transcription factors were identified on metabolic pathways of three pigments through correlation analyses and quantitative experiments. Furthermore, a R2R3-MYB transcription factor, FnMYB4, was confirmed to be positively correlated with flavonoid synthesis through transient overexpression, virus-induced gene silencing (VIGS), and RNA interference (RNAi), accompanying by reoccurrence and attenuation of mutant phenotype. Finally, dual-luciferase (LUC) and yeast one-hybrid assays confirmed the binding of FnMYB4 to the FnFLS and FnF3H promoters, indicating that FnMYB4 positively regulates flavonoid synthesis. In addition, correlation analyses suggested that FnMYB4 also might be involved in chlorophyll and carotenoid metabolisms. These findings demonstrated the pivotal regulatory role of FnMYB4 in strawberry leaf coloration.

Green Synthesis of Silver Nanoparticles and Testing its Effectiveness in Inhibiting E. coli, Staphylococcus Aureus Isolated from Urinary Tract Infections of Pregnant Women

The aim of the study was to identify the E. coli and S. aureus bacteria isolated from pregnant women with urinary tract infections that silver nanoparticles derived from green leaves inhibited. The silver nanoparticles showed inhibitory activity against these two types by Well diffusion method. towards bacteria. The result of the inhibition diameters by Well diffusion method were (35,33,30,25) for E.coli and (37,34,28,23) for S.aureus bacteria at concentrations (10,7.5,5,2.5)% respectively through the absence of colony growth on the surface of Muller Hunton agar plates at those concentrations. The use of nanoparticles as a result of their effective properties in inhibiting bacteria, provided that there are no side effects that affect its work. To make silver nanoparticles in an eco-friendly manner—that is, without heating the plant extract and solution or utilizing chemical catalysts during the reaction—one milliliter of strawberry leaf extract and fifty milliliters of silver nitrate solution—prepared at a concentration of one millimeter at room temperature for one to eight hours—were combined. Using UV spectrophotometers, scanning electron microscopy (SEM), XRD, and FTIR, it was determined that the preparation had begun when the mixture's color intensity increased after each of these eight hours had gone. The absorbance at 378 nm was visible in the UV-VIS spectrum. According to the results of scanning electron microscopy, the produced silver nanoparticles ranged in size from 37.35 nm. The biological method of producing silver nanoparticles in this low-cost and eco-friendly manner has shown promising results in preventing the growth of bacteria isolated from wound infections.

The biological control effect of Bacillus cereus on strawberry leaf spot disease caused by Neopestalotiopsis clavispora

With their distinctive flavor, fragrance, and nutritional value, strawberry (Fragaria × ananassa Duch.) fruits are popular worldwide. However, strawberry is susceptible to pathogenic fungi in production, which can severely affect yields. In this study, we found a fungal disease in strawberries in Shenyang. The pathogen was identified from morphological characteristics and molecular data as Neopestalotiopsis clavispora. This fungus causes enormous economic losses in strawberry cultivation and production. It is essential to explore effective methods of controlling this disease, including chemical fungicides and biocontrol agents. This study evaluated the antifungal activity of 17 Bacillus strains isolated from soil against N. clavispora. These Bacillus strains showed significant antagonistic effects, with inhibition rates in the dual culture test of 50.22 %–79.48 %. Among these, Bacillus cereus (Bce-2) had the highest inhibition rate of 79.48 %. The ability of different working concentrations of Bacillus cereus culture solution to inhibit mycelium growth was variable, when the working concentration of Bacillus cereus culture solution was 0 %, 2 %, 4 %, 6 % and 8 %, the mycelium dry weight was 0.05–0.52 g. Furthermore, we optimized the fermentation method and evaluated the ability of the Bacillus cereus fermentation solution (BCFS) to control this disease in the field, the disease index of strawberry plants pre-treated with BCFS was reduced by 57.85 %. BCFS treatment improved the activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and phenylalanine lyase (PAL). BCFS also prevents strawberry leaf spot disease caused by N. clavispora by increasing the expression of the following genes (WRKY22, WRKY29, ChiB, RbohD, HSP90, Rd19, PR1 and PP2C) in strawberry leaves. This study suggests that Bacillus cereus (Bce-2) may be effective in controlling N. clavispora.

Pan-Genomic Analysis Identifies the Chinese Strain as a New Subspecies of Xanthomonas fragariae.

Xanthomonas fragariae is classified as a quarantine pathogen by the European and Mediterranean Plant Protection Organization. It commonly induces typical angular leaf spot (ALS) symptoms in strawberry leaves. X. fragariae strains from China (YL19, SHAQP01, and YLX21) exhibit ALS symptoms in leaves and more severe symptoms of dry cavity rot in strawberry crowns. Conversely, strains from other countries do not cause severe dry cavity rot symptoms in strawberries. After employing multilocus sequence analysis (MLSA), average nucleotide identity (ANI), and amino acid identity (AAI), we determined that Chinese strains of X. fragariae are genetically distinct from other strains and can be considered a new subspecies. Subsequent analysis of 63 X. fragariae genomes published at NCBI using IPGA and EDGAR3.0 revealed the pan-genomic profile, with 1,680 shared genes present in all 63 strains, including 71 virulence-related genes. Additionally, we identified 123 genes exclusive to all the Chinese strains, encompassing 12 virulence-related genes. The qRT-PCR analysis demonstrated that the expression of XopD, XopG1, CE8, GT2, and GH121 out of 12 virulence-related genes of Chinese strains (YL19) exhibited a constant increase in the early stages (6, 24, 54, and 96 hours postinoculation [hpi]) of strawberry leaf infected by YL19. So, the presence of XopD, XopG1, CE8, GT2, and GH121 in Chinese strains may play important roles in the early infection process of Chinese strains. These findings offer novel insights into comprehending the population structure and variation in the pathogenic capacity of X. fragariae.

Neoseiulus agrestis as a biological agent, and monitoring of introducted thrips in greenhouses

Oligophagus Neoseiulus agrestis (Karg, 1960) can be used as predator on vegetable, flower and berry crops. It is capable of feeding on Tetranychidae and Tarsonemidae. The ability to regulate the number of Thripidae has been established. It lives in colonies of Acaridae mites. The technology of mass breeding allows to accumulate predator population in a loose substrate. The technology of use for this phytoseiid mite should be adapted to each type of plant taking into account the bioecological features. For a greenhouse cucumber, the release should be made at the trellis part of the plant. On flower crops, for example gloxinia, colonization is carried out by sowing the substrate with a predator on all plants in the greenhouse. It is effective on garden strawberries in the struggle against the strawberry mite Steneotarsonemus pallidus. The predator prefers to attack the nymphal stages and eggs of the Tetranychus urticae mite. It is capable of attacking not only the larvae of Thrips nigropilosus, but also its nymphs. In the garden strawberry leaf rosette, it destroys the strawberry mite, at penetration into the inner part of leaf buttons. It is highly sensitive to pesticides from the class of macrocyclic lactones and synthetic pyrethroids. Preparations based on the bacterium Bacillus thurengiensis on N. agrestis do not have a lethal effect.

Study of Technological Parameters and Pharmacological Activity of the Gel with Strawberry (<i>Fragaria ananassa</i>) Leaves with Dry Extract

Introduction. Interest in herbal preparations is increasing every year, as the variety of chemical composition and pharmacological action of plants makes it possible to discover and create drugs whose therapeutic effect is due to a complex of biologically active substances. It is important for the effective treatment of diseases to have a properly selected dosage form, which provides both ease of use and targeted use of the action of the pharmacologically active drug contained in it. Therefore, obtaining and introducing new plant extracts into medical practice can become promising in the field of creating soft dosage forms. Strawberry garden leaf extract dry (strawberry extract) is one of the potential substances for obtaining effective and safe medicines. According to the results of earlier studies conducted by the staff of the Perm State Pharmaceutical Academy of the Ministry of Health of the Russian Federation, a high anti-inflammatory activity of strawberry extract was proved, comparable to the activity of the synthetic drug Indomethacin. Studies of the chronic toxicity of the extract, allergenic, immunotoxic properties and reproductive toxicity in the framework of preclinical studies have shown the safety of the obtained extract and the possibility of using the substance for further development of medicines based on it. In this regard, the study of technological parameters and pharmacological activity of a soft dosage form based on strawberry extract is of practical interest for improving the drug supply of the population and expanding the range of medicines based on plant extracts with anti-inflammatory and antimicrobial effects.Aim. Development of a soft dosage form based on strawberry leaves of dry extract and study of its pharmacological activity.Materials and methods. For the study, gels with an active substance – strawberry leaves with dry extract (JSC "Biohimmash", Russia, shelf life – 2 years), the main components – sodium carboxymethylcellulose C75 (TU 2231-002-50277563-2000, LLC "Base chemical products "Yugreactive", Russia, 151118, term storage 3 years), methylcellulose 35 (TU 2231-107-57684455-2003, JSC "UZPH", Russia, 221218, shelf life 3 years), sodium alginate (TU 15-02-544-83, LLC "Base сhemical products "Yugreactive", Russia, 151018, shelf life 3 years), glycerol (FS.2.2.0006.15, JSC "Kupavnareaktiv", Russia, 082018, shelf life 3 years), purified water (FS FS.2.2.0020.18), obtained at the reverse osmosis unit UVOI-"MF" 1812S6 (JSC "NPK MEDIAN FILTER", Russia). Вiopharmaceutical and technological methods were used in the course of the research. Antimicrobial activity was determined according to the OFS.1.2.4.0010.15 by diffusion into agar. Anti-inflammatory activity was studied on a model of acute inflammatory edema caused by subplantar injection of 0.1 ml of 1 % aqueous solution of carrageenan into the hind paw of a rat. The obtained data were processed with the calculation of the Student's t-test for independent samples. The data were considered reliable at p < 0.05.Results and discussion. Based on technological, biopharmaceutical and pharmacological research methods, the composition of a gel from strawberry leaves with dry extract, which has antimicrobial and anti-inflammatory effects, was proposed and substantiated for the first time. The biopharmaceutical availability of the gel was determined by diffusion into agar gel. The antimicrobial activity of the gel from strawberry leaves with dry extract and its anti-inflammatory activity on the model of carrageenan edema with external application of the studied dosage forms were studied.Conclusion. The study shows the possibility of expanding the range of drugs for external use with antimicrobial and anti-inflammatory activity.

РАЗРАБОТКА СОСТАВА И ОПРЕДЕЛЕНИЕ ПОКАЗАТЕЛЕЙ КАЧЕСТВА СИРОПОВ С ИЗВЛЕЧЕНИЯМИ ИЗ СЫРЬЯ ФАРМАКОПЕЙНЫХ РАСТЕНИЙ СЕМЕЙСТВА ROSACEAE

The largest number of plant species included in the State Pharmacopoeia of the Russian Federation belong to the Rosaceae family. However, the number of phytopreparations based on this plant raw material in the domestic pharmaceutical market is not so diverse. Taking into account the growing popularity of the medicinal form of syrups, the authors conducted a study aimed at developing the composition and technology for producing syrups with rhizomes and roots of Sanguisorba (Sanguisorbae officinalis rhizomata et radices), rhizomes of Potentilla (Potentillae erectae rhizomata), leaves of wild strawberries (Fragariae vescae folia), fruits of aronia (dry) (Aroniae melanocarpae sicco fructus), rowan fruits (Sorbi aucupariae fructus), rosehip fruits (Rosae fructus), cherry fruits (Padi avii fructus). Syrups were obtained using a technology using liquid extracts in the composition, which were obtained in accordance with the requirements of the OFS.1.4.1.0021.15 Extracts. For all the syrups obtained, quality indicators were determined: density, pH, refractive index, microbiological frequency. To determine the quantitative content of biologically active substances in the developed syrups, the authors used the principle of end-to-end standardization, involving the use of the same quality control methods used in the standardization of the initial medicinal plant raw materials. The total content of tannins was determined for syrups with rhizomes and roots of medicinal hemophlebus, rhizomes of lapchatka, cherry fruits, the total content of anthocyanins was determined for the syrup of aronia fruits, the total content of anthocyanins was determined for the syrups of rowan and rosehip fruits, the content of ascorbic acid was determined and for strawberry leaf syrup the total content of flavonoids in terms of rutin. According to the results of the conducted studies, the norms of the content of active substances in the studied forms were recommended.

Response of strawberry (Fragaria ananassa L.) to chilling and potassium supply from inorganic and amino acid-complexed sources

There is growing evidence that plants need higher potassium (K) when subjected to environmental stresses i.e., chilling in order to tolerate oxidative damages provided by stress. In this work, influence of potassium (K) foliar spray from different fertilizer sources including K2SO4 and lysine (Lys)- and methionine (Met)-complexed K on physiological and antioxidative responses of strawberry (Fragaria ananassa ‘Gavieta’) to chilling (6 h d−1 at 4 °C for 3 consecutive days) was investigated. Chilling of control, Lys, and K-Lys-strawberry plants to 4 °C increased ion leakage and malondialdehyde (MDA) concentration. In contrast, chilling was ineffective on the amount of ion leakage and MDA in the plants supplied by K2SO4, K-Met, and only Met. The leaf chlorophyll concentration was found to reduce by chilling in both control (free of K and amino acid) and Lys-treatments, however, the chill-treatment leaf chlorophyll concentration remained unchanged in the plants supplied with K-Met, K2SO4, and only Met. The chilling at 4 °C resulted in between 0.58 % to 5.2-fold rise in strawberry leaf CAT, APX, and SOD activities, the largest increase was found at K-Met-treatment. Chilling substantially increased leaf proline concentration (on average 99.5 %), the largest increase was found at the K-Met-treatment. Chilling caused significant reduction in water potential (ΨL) and relative water content (RWC) of control and only Lys-and Met-strawberry plants but it had no effect on these water relations of K-fed plants. According to the results, foliar fertilization of K particularly from K-Met-complex was effective in alleviating the destructive effect of chilling on cell membrane of plant leaves. The protective effect of K and Met-fertilization against chilling-induced injuries was in part related to a substantial rise in leaf activity of CAT, APX, and SOD and leaf proline concentration.

Flagella-Driven Motility Is Critical to the Virulence of Xanthomonas fragariae in Strawberry.

Xanthomonas fragariae (X. fragariae) is the causal agent of angular leaf spots (ALS) in strawberry plants. Recently, a study in China isolated X. fragariae strain YL19, which was observed to cause both typical ALS symptoms and dry cavity rot in strawberry crown tissue; this was the first X. fragariae strain to have both these effects in strawberry. In this study, from 2020 to 2022, we isolated 39 X. fragariae strains from diseased strawberries in different production areas in China. Multilocus sequence typing (MLST) and phylogenetic analysis showed that X. fragariae strain YLX21 was genetically different from YL19 and other strains. Tests indicated that YLX21 and YL19 had different pathogenicities toward strawberry leaves and stem crowns. YLX21 did not cause ALS symptoms, rarely caused dry cavity rot in strawberry crown after wound inoculation, and never caused dry cavity rot after spray inoculation, but it did cause severe ALS symptoms after spray inoculation. However, YL19 caused more severe symptoms in strawberry crowns under both conditions. Moreover, YL19 had a single polar flagellum, while YLX21 had no flagellum. Motility and chemotaxis assays showed that YLX21 had weaker motility than YL19, which may explain why YLX21 tended to multiply in situ within the strawberry leaf rather than migrate to other tissues, causing more severe ALS symptoms and mild crown rot symptoms. Taken together, the new strain YLX21 helped us reveal critical factors underlying the pathogenicity of X. fragariae and the mechanism by which dry cavity rot in strawberry crowns forms.