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True mangroves and mangrove associates are salt‐tolerant trees and shrubs that serve a critical role in preserving the ecological balance of tropical and subtropical estuarine environments. However, they are not immune to the damage caused by fungal pathogens. In this study, leaves exhibiting leaf spot symptoms were gathered from mangrove estuary and forests in Prachuap Khiri Khan, Thailand. Through morphological and multilocus phylogenetic analyses (LSU, ITS, RPB2 and TUB2) along with genealogical concordance phylogenetic species recognition, we identified Allophoma acanthi sp. nov. from Acanthus ilicifolius. Additionally, A. minor was identified as the causative agent of leaf spots in true mangrove and mangrove associate species, namely, Acanthus ilicifolius, Combretum sp., Hibiscus tiliaceus, Intsia bijuga, Lumnitzera racemosa and Sonneratia alba. We also provide evidence to support the synonymization of A. thunbergiae with A. minor. All eight isolates of Allophoma species in this study demonstrated pathogenicity to their original hosts with varied virulence, confirming Koch's postulates. Our findings contribute to the understanding of fungal pathogens affecting true mangroves and mangrove associates. [ABSTRACT FROM AUTHOR]

Plantago lanceolata has been increasingly cultivated in recent years as a forage crop due to its high feeding quality, good adaptability and medicinal benefits. Between 2015 and 2023, Alternaria leaf spot (ALS), appearing as reddish‐brown necrotic spots with a greyish white to pale brown centre, was commonly observed in two forage germplasm nurseries of P. lanceolata of Sichuan Province, China. Initially, 139 Alternaria strains were isolated from leaf lesions, and then identified using the identity of rDNA internal transcribed spacer (ITS) sequences in the NCBI database and the similarity of morphological characteristics. By pure culture technique, six representative isolates were finally obtained for the present study. Based on both multilocus phylogeny (SSU, LSU, ITS, gapdh, rpb2, tef1, endoPG, OPA10‐2, alt a 1, KOG1058 and KOG1077) and morphology, four Alternaria species were identified: three new records of A. alternata, A. arborescens species complex and A. gossypina on this host in China, belonging to section Alternaria, and a new species of section Porri, namely, A. lanceolatae sp. nov. Pathogenicity tests by inoculation on both detached leaves and whole plants revealed that A. lanceolatae was the most important causal agent of ALS, while the other three species were nonpathogenic to P. lanceolata. This study characterized a novel pathogenic Alternaria species of section Porri from P. lanceolata in China and could contribute as useful research for possible ALS management. [ABSTRACT FROM AUTHOR]

BACKGROUND: Microstegium vimineum (Trin.) A. Camus, commonly called stiltgrass, is a dominant weed in the United States and China. Although a lot of control approaches have been attempted, an economic, effective and practical measure has not been available to control the weed so far. RESULTS: A serious rust disease of Microstegium vimineum was observed in three regions of Wenzhou city in China, from 2019 to 2021, with a disease incidence ranging from 82% to 97%. Typical rust disease symptoms on Microstegium vimineum were prominently visible during the early monsoon season (June–July), with chlorotic spots on the leaf surfaces. The morphological characterization of the strain WZ‐1 which was isolated from the diseased leaves was consistent with Puccinia polliniicola. The virulence tests showed that the average disease index of Microstegium vimineum plants could reach 35% at 10 days post‐inoculation. The host specificity of Puccinia polliniicola was tested on 64 plant species from 12 families and it did not cause any diseased symptoms on 24 major crops and 36 weeds, but slightly infected four gramineous weeds, Arthraxon hispidus, Polypogon fugax, Cynodon dactylon, and Microstegium ciliatum. However, newly‐produced urediniospores were not observed on the slightly infected plants. The urediniospores of strain WZ‐1 infected the Microstegium vimineum leaves by two main approaches: mycelium or appressorium invaded the stoma; and mycelium or appressorium directly invaded intercellular spaces. Field experiments showed that the rust disease naturally prevailed among Microstegium vimineum populations, causing severe rust disease symptoms on the leaf surface. The rust epidemic effectively controlled all of the target plants in the closed plot where the rust was released. CONCLUSION: Puccinia polliniicola strain WZ‐1 has great potential to be used as a classical biological control agent against Microstegium vimineum. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

'Kikatiti' pinto bean (Phaseolus vulgaris L.) (Reg. no. CV‐361, PI 705149) was developed by the dry bean breeding program at the University of Nebraska, Agricultural Research Division, and submitted for release in 2021 by the Sokoine University of Agriculture in Morogoro as an upright indeterminate pinto bean with high yield potential and multiple disease resistance across bean production environments in Tanzania. Kikatiti was officially released in 2024 by the National Seed Committee. Kikatiti is an F7:8 derived line developed using the pedigree breeding method in Nebraska. The exceptional performance of Kikatiti in Tanzania was first identified by evaluation of the Durango Diversity Panel (DDP), which consisted of 200 accessions in on‐station trials conducted in Arusha and Mbeya. Kikatiti was identified as accession DDP‐094 (advanced breeding line NE2‐09‐3). Kikatiti yielded 1584 kg ha−1 across 5 years of trials in Tanzania and matured in 89 days. Kikatiti is resistant to bean rust conferred by the Ur‐3 and Ur‐11 genes, resistant to all strains of Bean common mosaic virus and Bean common mosaic necrosis virus conferred by the I and bc‐3 genes, moderately resistant to common bacterial blight conferred by the SAP6 quantitative trait locus, avoids white mold disease due to its upright architecture, and is moderately susceptible to angular leaf spot disease. Kikatiti has large seed size (35.9 g 100 seeds−1), and in on‐farm trials, farmers ranked Kikatiti above local pinto cultivars for its performance and market potential. Kikatiti has the potential to expand pinto bean production across East Africa. Core Ideas: Kikatiti pinto bean has superior productivity in Tanzania.Kikatiti pinto possesses an effective combination of resistance genes to combat bean rust disease in East Africa.Kikatiti pinto possesses an effective combination of resistance genes to combat Bean common mosaic necrosis virus.Farmers ranked Kikatiti above local pinto cultivars for performance and market potential in on‐farm trials. [ABSTRACT FROM AUTHOR]

Maize, as well as other plants, are particularly susceptible to various illnesses. Therefore, one of the most crucial ways for farmers to prevent crop loss is through early diagnosis of plant diseases. The application of deep convolutional neural networks (CNN) for disease identification in maize plants can aid farmers in quickly and reliably detecting the presence of illnesses. In this regard, we have taken 4,988 images belonging to three distinct but widespread types of maize illnesses: Leaf-blight, Common Rust, and Gray Leaf Spot. Moreover, all these images are fed to 13 different pre-trained CNN models such as Alexnet, Densenet201, Googlenet, InceptionresnetV2, InceptionV3, MobilenetV2, VGG-16, VGG-19, Resnet-18, Resnet-50, Resnet-101, Xception and Shufflenet for training as well as testing. The performance of all these CNN models is recorded with reference to accuracy, specificity, precision, False Positive Rate, F1 Score, MCC, and Kappa. Then the effectiveness of each model is evaluated through multiclass statistical analysis by the IBM SPSS statistics tool to select the most efficient classification model among all above said 13 models. The comparison results show, among all the models, Densenet201 has the highest accuracy with the lowest False Positive Rate (FPR), whereas VGG-19 has the lowest accuracy with the highest False Positive Rate for the identification of mentioned maize diseases. [ABSTRACT FROM AUTHOR]

Plant spotted leaf (spl) mutants are useful to reveal the regulatory mechanisms of immune responses. Thus, in crop plants, their agronomic traits, especially the grain quality are usually ignored. Here, we characterized a rice spl mutant named spl-A (spotted leaf mutant from A814) that shows autoimmunity, broadspectrum disease resistance and growth deterioration including decreased rice quality. A single nucleotide mutation of C1144T, which leads to change of the 382nd proline to serine, in the gene encoding the ATPases associated with diverse cellular activities (AAA)-type ATPase LRD6-6 is responsible for the phenotype of the spl-A mutant. Mechanistically, this mutation impairs LRD6-6 ATPase activity and disrupts its interaction with endosomal sorting complex required for transport (ESCRT)-III subunits OsSNF7.1/7.2/7.3. And thus, leading to compromise of multivesicular bodies (MVBs)-mediated vesicle trafficking and accumulation of ubiquitinated proteins in both leaves and seeds of spl-A. Therefore, the immune response of spl-A is activated, and the growth and grain quality are deteriorated. Our study identifies a new amino acid residue that important for LRD6-6 and provides new insight into our understanding of how MVBs-mediated vesicle trafficking regulates plant immunity and growth, including grain quality in rice. [ABSTRACT FROM AUTHOR]

Grapevine (Vitis vinifera) is one of the significant fruit trees cultivated in Iraq. During 2018-2019, severe leaf spot symptoms were observed commonly on grapevine in Al-Hussainiya district, Karbala province, Iraq. In order to identify the etiology of this disease, symptomatic leaf samples were collected randomly. The associated fungus was isolated, purified and identified as Alternaria alternata according to its morphological characteristics and sequence analyses of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA). The pathogenicity assay using Koch's postulates approved that the isolated A. alternata was pathogenic on grapevine leaves. The current study represents the first record of A. alternata causing leaf spots on grapevine in Karbala province, Iraq. [ABSTRACT FROM AUTHOR]

Reliance on visual inspection for Maize leaf disease identification proves unreliable, often resulting in inappropriate pesticide application and associated health hazards. Food security requires precise and automated disease detection methods to save time and prevent crop losses. Although several studies have used deep and machine learning to detect plant leaf diseases from different perspectives, most of them require numerous training parameters or have low classification accuracy. Furthermore, a model that was developed for one region of the world might not be appropriate for another due to distinctions in morphology and other aspects. In this context, an application for mobile phones was developed that recognizes and classifies maize leaf diseases using a CNN-based pretrained VGG16 architecture. The model can detect northern corn leaf blight, common rust, and gray leaf spots in maize leaves in tropical climates. A total of 3024 images were used to generate the underlying model, including publicly available and field-collected images. The established model uses fewer training parameters to attain a training accuracy of 95.16% and a testing accuracy of 93%. The model provides farmers with an early warning system for early detection of plant diseases, enabling them to take preventive measures before significant production deficits occur. [ABSTRACT FROM AUTHOR]

Areca ipot, a Philippine endemic species, is categorized as endangered primarily due to habitat loss. A severe outbreak of a new leaf spot disease was observed on A. ipot seedlings in a nursery. Morphological and molecular features of isolates from diseased samples were identified as Neopestalotiopsis sp. and Calonectria sp. The pathogenicity of the isolates was confirmed by fulfilling Koch's postulates. This is the first report of Neopestalotiopsis sp. and Calonectria sp. causing leaf spot on A. ipot in the Philippines. [ABSTRACT FROM AUTHOR]

Tectona grandis is a vital hardwood tree species with substantial industrial and economic importance. From 2020 to 2021, an unusual leaf blight disease was observed in T. grandis saplings planted in the Nursery of the Central Agroforestry Research Institute (CAFRI), Jhansi, India. Disease incidence was recorded as 50%–70% with 40%–82% severity over two consecutive years on over 1000 saplings. The leaf blight disease was extensive, leading to defoliation of young leaves and mortality of teak saplings in the nursery. The pathogen was identified as Alternaria alternata following standard laboratory procedures and sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA). The pathogenicity of two isolates, A. alternata TgAa1 and TgAa2, was proven under greenhouse conditions. Phylogenetic analysis revealed the close association of TgAa1 and TgAa2 with other pathogenic A. alternata strains in the NCBI database. A. alternata is considered a severe foliar pathogen, known to cause leaf spot and leaf blight diseases in many annual and perennial plant species. Correct diagnosis and prevention are emphasized to contain the spread of teak leaf blight to other regions in India. This is the first report of A. alternata causing Tectona grandis leaf blight in the Bundelkhand region of India. [ABSTRACT FROM AUTHOR]

Interest in plant pathogens for classical biological control (CBC) of invasive introduced plants has increased steadily since the 1970s. The introduced plant Passiflora foetida sensu lato invades large tracts of land across northern Australia and CBC represents a possible solution to reduce its abundance and spread. Field surveys for foliar fungal pathogens of P. foetida s.l. were performed between 2017 and 2020 in Colombia. Molecular sequencing was used to confirm the identity of plants surveyed at each site and to explore genetic variation between sites. Leaf spots of various sizes and sometime associated with chlorosis as well as necrosis of leaf edges were the main disease symptoms observed. These symptoms were not severe and did not appear to affect plant growth. No disease symptoms caused by obligate biotrophic fungi nor girdling lesions on stems were observed. Of the 125 fungal isolates recovered from the collected diseased material, only 21 were considered as pathogenic on P. foetida s.l. in detached-leaf assays. Morphological examinations and sequencing of the 21 pathogenic isolates revealed that they belong to 11 genera. Based on the low severity of disease symptoms observed in the field, we conclude that these isolates do not warrant further investigations as potential CBC agents. [ABSTRACT FROM AUTHOR]

Leaf spot, a major apple disease, manifests in diverse symptoms. In this study, the pathogen was isolated from diseased 'Yanfu 3' apple leaves in Yantai, Shandong Province, and identified as Neopestalotiopsis clavispora through morphological observation, molecular identification, and multi-gene (ITS, TEF1α, and TUB2) phylogenetic analysis. Three isolates (YTNK01, YTNK02, and YTNK03) were selected for pathogenicity tests to verify Koch's postulates. To our knowledge, this is the first report of N. clavispora being responsible for apple leaf spots in China, and the disease has been named 'apple Neopestalotiopsis leaf spot'. Additionally, N. clavispora was found to infect crabapple, sweet cherry, grape, peach, and pear under laboratory conditions, indicating that these fruit trees may be potential hosts for N. clavispora in the field. The in vitro toxicity of ten fungicides to the pathogen was assessed using the mycelial growth rate method. All ten fungicides were effective in inhibiting the growth of N. clavispora. Among them, those based on pylocyanonitrile, propiconazole, pyraclostrobin, tebuconazole, diphenoxazole, and osthole showed higher toxicity to N. clavispora, with EC50 values of 0.11, 0.41, 0.47, 1.32, 1.85, and 3.82 µg/mL, respectively. These fungicides could be used as alternatives to prevent this disease in production. Overall, these findings provide valuable insights into the characteristics of N. clavispora causing apple leaf spot and are crucial for developing effective management strategies. [ABSTRACT FROM AUTHOR]

Apple canker disease, also named as apple Valsa canker, is one of the most destructive diseases for apples (Malus domestica Borkh.). Cytospora/Valsa spp. are the dominant causal agent of this disease, but many studies have revealed that fungi from some other genus can also cause typical apple canker symptoms. In this study, we performed fungal pathogen isolation from cankered 'Fuji' apple barks. Six representative morphologically different fungi (Strain 1–6) were further subjected to ITS sequencing and evolutionary analysis. Molecular identification results revealed that Strains 1–6 are Cytospora mali, Fusarium cf. solani, Alternaria alternata, C. mali, Diplodia seriata and F. proliferatum, respectively. All these fungi have been reported to be causal agents of apple diseases. By inoculating fungal plugs onto trunks of 'Fuji' apple trees, the pathogenicity of the six fungi were accessed. Only the inoculations of the two C. mali strains (Strain 1 and Strain 4) and the A. alternata strain (Strain 3) resulted in typical apple canker symptoms in trunks. It is worth noting that Strain 1 caused much more severe canker symptoms and higher pathogenicity incidence than the other two fungi. A. alternata has been identified as a pathogen causing diseases on apple fruits and leaves. By further assessing its pathogenicity on apple fruits and leaves, we verified that it can also cause typical fruit rot and leaf spot symptoms. To the best of our knowledge, this is the first report on apple canker disease caused by A. alternata in China. Our present study can provide a theoretical foundation for the prevention and control of apple canker disease. [ABSTRACT FROM AUTHOR]

Difenoconazole-loaded (CS-DIF) microcapsules were synthesized by encapsulating difenoconazole into biocompatible chitosan. The physical and chemical properties indicated that the encapsulation and chemical loading rates were 85.58% and 61.98%, respectively. The microcapsules exhibited prominent controlled-release and surface stability performance. The cumulative release rate was only 33.6% in 168 h, and the contact angle decreased by 11.73° at 120 s compared with difenoconazole. The antifungal activity of the CS-DIF microcapsules against Curvularia lunata was confirmed through observations of colony growth, in vitro and in vivo inoculation, mycelium morphology, as well as DNA and protein leakage. The antioxidant enzyme activity of superoxide dismutase, peroxidase, and catalase decreased by 65.1%, 84.9%, and 69.7%, respectively, when Curvularia lunata was treated with 200 μg/mL microcapsules, compared with the control in 24 h. The enzymatic activity of polyphenol oxidase decreased by 323.8%. The reactive oxygen species contents of hydrogen peroxide and superoxide anions increased by 204.6% and 164%, respectively. Additionally, the soluble sugar and soluble protein contents decreased by 65.5% and 69.6%, respectively. These findings provided a novel approach to control the growth of C. lunata efficiently, laying a foundation for reducing the quantity and enhancing the efficiency of chemical pesticides. The CS-DIF microcapsules exhibited a strong inhibitory effect on fungus, effectively preventing and controlling leaf spot disease and showing potential for field applications. This study might be of great significance in ensuring plant protection strategies. [ABSTRACT FROM AUTHOR]

Ramularia leaf spot of barley, caused by Ramularia collo-cygni has become a serious disease threat to barley production. By inducing necrotic lesions, the disease expiates the onset of leaf senescence, which can result in significant grain yield and quality losses. In addition to surviving between seasons in trash, stubble and volunteers, R. collo-cygni can be transmitted from seed to emerging seedlings. As a potential additional means of transmission it may also pose a risk for the spread of specific traits such as fungicide resistance. In the present study, we screened Irish barley seed stocks harvested in the years 2015–2017 for the presence of R. collo-cygni using qPCR, and subsequently using an amplicon sequencing assay screened for the presence of alleles in the SDHC gene of R. collo-cygni associated with SDHI resistance. Over the three year period > 60% of the samples screened had detectable levels of R. collo-cygni present. In a subsample of these five alleles associated with resistance (SDHC—N87S, G91R, H145R, R152M and H153R) were detected. The prevalence of the key alleles C-N87S and C-H146R remained stable over the three year period, and was similar to that detected amongst an isolate collection established in 2022. [ABSTRACT FROM AUTHOR]

Barley crops are at risk of being attacked by several leaf diseases. Net blotch, brown rust, Rhynchosporium and Ramularia leaf spot are among the most widespread and can cause severe attack and yield losses. Two trial protocols targeting Ramularia and net blotch, respectively, have been tested in several countries in 2021 and 2022. Ramularia trials were situated in Germany, Ireland, Scotland, and Denmark. The net blotch trials were placed in Denmark, Belgium, the UK, Germany, Finland, and France. In the two protocols, 12–13 different fungicide solutions including co-formulations of DMIs, SDHIs, QoIs, and multi-site inhibitors have been tested to compare efficacy and yield responses. Against Ramularia leaf spot, the fungicides were applied at GS 47–51 and against net blotch at GS 37–45. In six trials, the efficacy against Ramularia leaf spot was scored. The results showed a superior control from the co-formulation fluxapyroxad + metyltetraprole (78–100% control), but also solo mefentrifluconazole and the mixtures fluxapyroxad + mefentrifluconazole performed well (average 74–76% control). The mixture fluxapyroxad + metyltetraprole provided the best yield increase followed by Ascra Xpro. Folpet as a solo solution was inferior. Following the net blotch protocol, only three trials developed enough disease to rank the different fungicides; however, in five trials ranking against brown rust was also possible. Most treatments gave very good control of net blotch, and brown rust (> 80% control). The mixture fluxapyroxad + metyltetraprole delivered the best control against all diseases overall. Average yield responses from eight trials showed very similar increases from the tested fungicides. [ABSTRACT FROM AUTHOR]

Summary: Glomerella leaf spot (GLS), caused by the fungus Colletotrichum fructicola, is considered one of the most destructive diseases affecting apples. The VQ‐WRKY complex plays a crucial role in the response of plants to biotic stresses. However, our understanding of the defensive role of the VQ‐WRKY complex on woody plants, particularly apples, under biotic stress, remains limited. In this study, we elucidated the molecular mechanisms underlying the defensive role of the apple MdVQ37‐MdWRKY100 module in response to GLS infection. The overexpression of MdWRKY100 enhanced resistance to C. fructicola, whereas MdWRKY100 RNA interference in apple plants reduced resistance to C. fructicola by affecting salicylic acid (SA) content and the expression level of the CC‐NBS‐LRR resistance gene MdRPM1. DAP‐seq, Y1H, EMSA, and RT‐qPCR assays indicated that MdWRKY100 inhibited the expression of MdWRKY17, a positive regulatory factor gene of SA degradation, upregulated the expression of MdPAL1, a key enzyme gene of SA biosynthesis, and promoted MdRPM1 expression by directly binding to their promotors. Transient overexpression and silencing experiments showed that MdPAL1 and MdRPM1 positively regulated GLS resistance in apples. Furthermore, the overexpression of MdVQ37 increased the susceptibility to C. fructicola by reducing the SA content and expression level of MdRPM1. Additionally, MdVQ37 interacted with MdWRKY100, which repressed the transcriptional activity of MdWRKY100. In summary, these results revealed the molecular mechanism through which the apple MdVQ37‐MdWRKY100 module responds to GLS infection by regulating SA content and MdRPM1 expression, providing novel insights into the involvement of the VQ‐WRKY complex in plant pathogen defence responses. [ABSTRACT FROM AUTHOR]

In June 2020, branch canker and brown spot of leaves on walnut were observed in Qingyang, China. A total of five strains were isolated from symptomatic samples and verified for pathogenicity based on Koch's Postulates, which showed that strains Hz4–1, Hz5–2, and Hy3–1 were the causative agents, and preliminarily identified them as members of the genus Nothophoma based on morphological characteristics. Subsequently, multi-locus phylogenetic analysis of the partial sequences of internal transcribed spacer (ITS), nuclear large ribosomal subunit (LSU), partial β-tubulin (TUB2), and RNA polymerase II second largest subunit (RPB2) showed that the three strains were clustered into two groups on the phylogenetic tree: strain Hz4–1 and Hz5–2 and Nothophoma quercina (CBS 6633.92) clustered into one branch with 84% support, while Hy3–1 and Nothophoma spiraeae (CFCC 53 929) clustered within a well-supported clade with a bootstrap value of 99%. As a result, combining morphological characteristics and multi-locus systematic analysis, the strains Hz4–1 and Hz5–2 were identified as N. quercina, and Hy3–1 was identified as N. spiraeae, which is the first report of N. spiraeae causing walnut disease in China. [ABSTRACT FROM AUTHOR]

Citrus trees are affected by many plant‐pathogenic fungi. The present study aimed to characterize Colletotrichum species on citrus showing anthracnose symptoms, leaf and fruit spot and wither tip in northern Thailand using multilocus data and assay their pathogenicity. The surveys were carried out from December 2021 to January 2022 and 73 isolates were obtained from infected tissues. The fungal strains were identified based on morphological traits and were confirmed via amplification and sequencing of ITS, ACT, CHS‐1, GAPDH and TUB2. In all, 41 isolates were subjected to multilocus phylogeny. Forty of these isolates of Colletotrichum species belonged to the C. gloeosporioides species complex and one isolate belonged to the C. orchidearum species complex. Colletotrichum siamense, comprising 19 isolates, was the most dominant species associated with symptomatic citrus, followed by C. gloeosporioides (17 isolates), C. fructicola (three isolates), C. endophytica (one isolate) and C. plurivorum (one isolate). C. plurivorum is reported for the first time from citrus in the world. These isolates were obtained from mandarin (Citrus reticulata), pomelo (C. maxima), Persian lime (C. latifolia), Thai lime (C. hystrix) and acid lime (C. aurantifolia). The pathogenicity of the isolated fungi was tested through inoculation on branch, fruit and leaf using the detached method on mandarin, pomelo and Persian lime hosts, confirming Koch's postulate. In terms of disease severity, C. gloeosporioides and C. siamense were observed to be the most pathogenic species. This is the first pathogenic and molecular study of Colletotrichum species infecting citrus in northern Thailand. [ABSTRACT FROM AUTHOR]

Plenodomus lingam (Leptosphaeria maculans) and P. biglobosus (L. biglobosa) are fungi causing Phoma leaf spot/stem canker, an international damaging disease of oilseed rape (Brassica napus) and other brassicas. In Europe, fungicides used for disease management are mainly sterol 14α‐demethylase (CYP51) inhibitors (DMIs/azoles); quinone‐outside inhibitors (QoIs) and succinate dehydrogenase inhibitors (SDHIs) are also used. Decreased DMI sensitivity has emerged in Australian and eastern European P. lingam populations and is mediated by CYP51 promoter inserts resulting in target site overexpression. In this study using in vitro sensitivity testing, we report decreased DMI (prothioconazole‐desthio, mefentrifluconazole) sensitivity in modern western European P. lingam isolates (collected 2022–2023) compared to older baseline (1992–2005) isolates. Around 85% of modern western European P. lingam isolates collected, for which the CYP51 promoter region was sequenced, carried a promoter insert, but target site alterations were not detected. Six different CYP51 promoter inserts were identified, most commonly a 237 bp fragment of the Sahana transposable element. Inserts were associated with an approximately 3‐ to 10‐fold decrease in sensitivity to the DMIs tested. In contrast to P. lingam, PCR screening revealed CYP51 promoter inserts were absent in modern western European P. biglobosus isolates (2021–2023). Combined data indicate P. lingam isolates lacking an insert were similarly (or slightly more) sensitive to the DMIs tested for P. biglobosus, whereas those carrying an insert were slightly less sensitive than P. biglobosus. No evidence for substantive sensitivity shifts to the QoI (pyraclostrobin) or SDHI (boscalid) fungicides tested was obtained for either Plenodomus species. [ABSTRACT FROM AUTHOR]

The rubber tree (Hevea brasiliensis) is one of the major domesticated crops planted commercially for the production of natural rubber (NR) worldwide. In recent years, rubber trees in the Southern states of India and other rubber-producing countries have experienced a severe leaf spot disease, characterized by the appearance of several brown circular spots in the initial stage, which later spread all over the lamina of fully matured leaves, leading to yellowing and defoliation. The causal organism of this Circular Leaf Spot (CLS) disease has not been conclusively identified in any previous studies. In this study, we collected infected leaf samples from various locations in the South Indian states. We aimed to identify the actual fungal pathogen that causes the CLS disease on rubber trees. Based on the morphological and molecular analysis of the most frequently isolated fungi from infected leaf samples were identified as Colletotrichum siamense and Colletotrichum fructicola. Pathogenicity tests also confirmed the involvement of isolated Colletotrichum spp. in the development of CLS disease. These findings provide valuable insights into understanding the CLS disease and its impact on rubber cultivation. To our knowledge, it is the first report of C. siamense and C. fructicola associated with CLS disease of rubber trees in India. [ABSTRACT FROM AUTHOR]

The productivity and quality of strawberries in southern Brazil are affected by the lack of cultivars adapted to different regions and by their susceptibility to diseases. This study aims to evaluate the resistance of cultivars and genotypes to mycosphaerella leaf spot (MLS) and powdery mildew (PM) and the quantitative and qualitative fruit agronomic parameters (FAP) of strawberries in southern Brazil during the 2019/2020 and 2020/2021 growing seasons. The incidence and severity of MLS and PM were evaluated from the beginning of symptoms appearances until harvest. Cultivars and genotypes were compared based on the area under the incidence (AUIDPC) and severity (AUSDPC) disease progress curves and the quantitative and qualitative FAP. The data were subjected to analysis of variance, and multivariate analysis was performed using principal component analysis (PCA). The cultivars Irma, Bellalinda, Kiara, Jonica, and Pircinque exhibited the lowest values of AUIDPC and AUSDPC, demonstrating the highest resistance to MLS and PM. The cultivars Kiara, Jonica, and Pircinque, along with genotype FRF LAM 119.1, showed the best qualitative and quantitative FAP. However, the FRF LAM 119.1 genotype exhibited the highest values of AUIDPC and AUSDPC, indicating high susceptibility to MLS and PM. CPA data indicated that the cultivars Kiara, Jonica, and Pircinque had the highest level of resistance, which was associated with the highest total fruit yield and the best fruit quality in terms of skin color and flavor balance. Kiara, Jonica, and Pircinque proved to be good options for strawberry production in southern Brazil, combining resistance to MLS and PM with good FAP. [ABSTRACT FROM AUTHOR]

Ascochyta blights cause yield losses in all major legume crops. Spring black stem (SBS) and leaf spot disease is a major foliar disease of Medicago truncatula and Medicago sativa (alfalfa) caused by the necrotrophic fungus Ascochyta medicaginicola. This present study sought to identify candidate genes for SBS disease resistance for future functional validation. We employed RNA-seq to profile the transcriptomes of a resistant (HM078) and susceptible (A17) genotype of M. truncatula at 24, 48, and 72 h post inoculation. Preliminary microscopic examination showed reduced pathogen growth on the resistant genotype. In total, 192 and 2,908 differentially expressed genes (DEGs) were observed in the resistant and susceptible genotype, respectively. Functional enrichment analysis revealed the susceptible genotype engaged in processes in the cell periphery and plasma membrane, as well as flavonoid biosynthesis whereas the resistant genotype utilized calcium ion binding, cell wall modifications, and external encapsulating structures. Candidate genes for disease resistance were selected based on the following criteria; among the top ten upregulated or downregulated genes in the resistant genotype, upregulated over time in the resistant genotype, hormone pathway genes, plant disease resistance genes, receptor-like kinases, contrasting expression profiles in QTL for disease resistance, and upregulated genes in enriched pathways. Overall, 22 candidate genes for SBS disease resistance were identified with support from the literature. These genes will be sources for future targeted mutagenesis and candidate gene validation potentially helping to improve disease resistance to this devastating foliar pathogen. [ABSTRACT FROM AUTHOR]

Field peas are grown by smallholder farmers in Ethiopia for food, fodder, income, and soil fertility. However, leaf diseases such as ascochyta blight, powdery mildew, and leaf spots affect the quantity and quality of this crop as well as crop growth. Experts use visual observation to detect field pea disease. However, this approach is expensive, labor-intensive, and imprecise. Therefore, in this study, we presented a transfer learning approach for the automatic diagnosis of field pea leaf diseases. We classified three field pea leaf diseases: Ascochyta blight, leaf spot, and powdery mildew. A softmax classifier was used to classify the diseases. A total of 1600 images of both healthy and diseased leaves were used to train, validate, and test the pretrained models. According to the experimental results, DenseNet121 achieved 99.73% training accuracy, 99.16% validation accuracy, and 98.33% testing accuracy after 100 epochs. we expect that this research work will offer various benefits for farmers and farm experts. It reduced the cost and time needed for the detection and classification of field pea leaf disease. Thus, a fast, automated, less costly, and accurate detection method is necessary to overcome the detection problem. [ABSTRACT FROM AUTHOR]

Diseases such as anthracnose (Colletotrichum lindemuthianum) and angular leaf spot (Pseudocercospora griseola) can occur in common bean and compromise crop production, especially if susceptible cultivars are grown under conditions favorable to these diseases. The most efficient and sustainable alternative for controlling these diseases is the use of resistant cultivars. The identification of sources of resistance and the use of tools that assist in accurate selection of resistant cultivars are crucial to the success of breeding programs. The aim of this study was to characterize 67 carioca common bean cultivars recommended in Brazil regarding reaction to races 65, 73, 81, and 89 of C. lindemuthianum and to races 63‐23 and 63‐63 of P. griseola and to verify the application of factor analysis in the selection of cultivars resistant to both pathogens. The cultivars and resistant controls BRS Esplendor and MAIII.16‐159 were inoculated in a greenhouse in two experiments for each race. Cultivars were assessed for resistance to multiple races of anthracnose and angular leaf spot using artificial inoculation of plants at V2 stage. Factor analysis proved to be a good alternative for accurate selection of resistant cultivars. The percentage of cultivars simultaneously resistant to all races was low (8.95%). The cultivars Rudá R, VC 15, IAC‐Apuã, IAC‐Carioca Pyatã, BRSMG Amuleto, and BRS FC104 selected by factor analysis showed resistance to anthracnose and angular leaf spot. Therefore, these cultivars are potential sources of resistance for incorporation in bean breeding programs. [ABSTRACT FROM AUTHOR]

Optimization of a breeding program requires assessing and quantifying empirical genetic trends made through past efforts relative to the current breeding strategies, germplasm, technologies, and policy. To establish the genetic trends in the Kenyan Highland Maize Breeding Program (KHMP), a two-decade (1999-2020) historical dataset from the Preliminary Variety Trials (PVT) and Advanced Variety Trials (AVT) was analyzed. A mixed model analysis was used to compute the genetic gains for traits based on the best linear unbiased estimates in the PVT and AVT evaluation stages. A positive significant genetic gain estimate for grain yield of 88 kg ha-1 year-1 (1.94% year-1) and 26 kg ha-1 year-1 (0.42% year-1) was recorded for PVT and AVT, respectively. Root lodging, an important agronomic trait in the Kenya highlands, had a desired genetic gain of -2.65% year-1 for AVT. Results showed improvement in resistance to Turcicum Leaf Blight (TLB) with -1.19% and -0.27% year-1 for the PVT and AVT, respectively. Similarly, a significant genetic trend of -0.81% was noted for resistance to Gray Leaf Spot (GLS) in AVT. These findings highlight the good progress made by KHMP in developing adapted maize hybrids for Kenya's highland agroecology. Nevertheless, the study identified significant opportunities for the KHMP to make even greater genetic gains for key traits with introgression of favorable alleles for various traits, implementing a continuous improvement plan including markerassisted forward breeding, sparse testing, and genomic selection, and doubled haploid technology for line development. [ABSTRACT FROM AUTHOR]

Rhizome rot is a destructive soil-borne disease of Polygonatum kingianum and adversely affects the yield and sustenance of the plant. Understanding how the causal fungus Fusarium oxysporum infects P. kingianum may suggest effective control measures against rhizome rot. In germinating conidia of infectious F. oxysporum, expression of the zinc finger transcription factor gene Zfp1, consisting of two C2H2 motifs, was up-regulated. To characterize the critical role of ZFP1, we generated independent deletion mutants (zfp1) and complemented one mutant with a transgenic copy of ZFP1 (zfp1 tZFP1). Mycelial growth and conidial production of zfp1 were slower than those of wild type (ZFP1) and zfp1 tZFP1. Additionally, a reduced inhibition of growth suggested zfp1 was less sensitive to conditions promoting cell wall and osmotic stresses than ZFP1 and zfp1 tZFP1. Furthermore pathogenicity tests suggested a critical role for growth of zfp1 in infected leaves and rhizomes of P. kingianum. Thus ZFP1 is important for mycelial growth, conidiation, osmoregulation, and pathogenicity in P. kingianum. [ABSTRACT FROM AUTHOR]

Background: Alternaria alternata is the primary pathogen of potato leaf spot disease, resulting in significant potato yield losses globally. Endophytic microorganism-based biological control, especially using microorganisms from host plants, has emerged as a promising and eco-friendly approach for managing plant diseases. Therefore, this study aimed to isolate, identify and characterize the endophytic fungi from healthy potato leaves which had great antifungal activity to the potato leaf spot pathogen of A. alternata in vitro and in vivo. Results: An endophytic fungal strain SD1-4 was isolated from healthy potato leaves and was identified as Talaromyces muroii through morphological and sequencing analysis. The strain SD1-4 exhibited potent antifungal activity against the potato leaf spot pathogen A. alternata Lill, with a hyphal inhibition rate of 69.19%. Microscopic and scanning electron microscope observations revealed that the strain SD1-4 grew parallel to, coiled around, shrunk and deformed the mycelia of A. alternata Lill. Additionally, the enzyme activities of chitinase and β-1, 3-glucanase significantly increased in the hyphae of A. alternata Lill when co-cultured with the strain SD1-4, indicating severe impairment of the cell wall function of A. alternata Lill. Furthermore, the mycelial growth and conidial germination of A. alternata Lill were significantly suppressed by the aseptic filtrate of the strain SD1-4, with inhibition rates of 79.00% and 80.67%, respectively. Decrease of leaf spot disease index from 78.36 to 37.03 was also observed in potato plants treated with the strain SD1-4, along with the significantly increased plant growth characters including plant height, root length, fresh weight, dry weight, chlorophyll content and photosynthetic rate of potato seedlings. Conclusion: The endophyte fungus of T. muroii SD1-4 isolated from healthy potato leaves in the present study showed high biocontrol potential against potato leaf spot disease caused by A. alternata via direct parasitism or antifungal metabolites, and had positive roles in promoting potato plant growth. [ABSTRACT FROM AUTHOR]

Monitoring genetic gains within breeding programs is a critical component for continuous improvement. While several national breeding programs in Africa have assessed genetic gain using era studies, this study is the first to use two decades of historical data to estimate genetic trends within a national breeding program. The objective of this study was to assess genetic trends within the final two stages of Zimbabwe's Department of Research & Specialist Services maize breeding pipeline between 2002 and 2021. Data from 107 intermediate and 162 advanced variety trials, comprising of 716 and 398 entries, respectively, was analyzed. Trials were conducted under optimal, managed drought stress, low nitrogen stress, low pH, random stress, and disease pressure (maize streak virus (MSV), grey leaf spot (GLS), and turcicum leaf blight under artificial inoculation. There were positive and significant genetic gains for grain yield across management conditions (28-35 kg ha-1 yr-1), under high-yield potential environments (17-61 kg ha-1 yr-1), and under low-yield potential environments (0-16 kg ha-1 yr-1). No significant changes were observed in plant and ear height over the study period. Stalk and root lodging, as well as susceptibility to MSV and GLS, significantly decreased over the study period. New breeding technologies need to be incorporated into the program to further increase the rate of genetic gain in the maize breeding programs and to effectively meet future needs. [ABSTRACT FROM AUTHOR]

Background: Early blight and brown leaf spot are often cited as the most problematic pathogens of tomato in many agricultural regions. Their causal agents are Alternaria spp., a genus of Ascomycota containing numerous necrotrophic pathogens. Breeding programs have yielded quantitatively resistant commercial cultivars, but fungicide application remains necessary to mitigate the yield losses. A major hindrance to resistance breeding is the complexity of the genetic determinants of resistance and susceptibility. In the absence of sufficiently resistant germplasm, we sequenced the transcriptomes of Heinz 1706 tomatoes treated with strongly virulent and weakly virulent isolates of Alternaria spp. 3 h post infection. We expanded existing functional gene annotations in tomato and using network statistics, we analyzed the transcriptional modules associated with defense and susceptibility. Results: The induced responses are very distinct. The weakly virulent isolate induced a defense response of calcium-signaling, hormone responses, and transcription factors. These defense-associated processes were found in a single transcriptional module alongside secondary metabolite biosynthesis genes, and other defense responses. Co-expression and gene regulatory networks independently predicted several D clade ethylene response factors to be early regulators of the defense transcriptional module, as well as other transcription factors both known and novel in pathogen defense, including several JA-associated genes. In contrast, the strongly virulent isolate elicited a much weaker response, and a separate transcriptional module bereft of hormone signaling. Conclusions: Our findings have predicted major defense regulators and several targets for downstream functional analyses. Combined with our improved gene functional annotation, they suggest that defense is achieved through induction of Alternaria-specific immune pathways, and susceptibility is mediated by modulating hormone responses. The implication of multiple specific clade D ethylene response factors and upregulation of JA-associated genes suggests that host defense in this pathosystem involves ethylene response factors to modulate jasmonic acid signaling. [ABSTRACT FROM AUTHOR]

This study elucidates the causative agent of a leaf spot in Commelina benghalensis, grown nearby a tomato field, through a polyphasic approach. Pathogenicity of the causative agent to C. benghalensis and cross infectivity to tomato was performed. Morphological, cultural, and molecular characterization identified the fungal isolate as Corynespora cassiicola. C. cassiicola CB005 produced leaf spot symptoms to C. benghalensis and tomato in all three independent trials. The same fungus was reisolated from the inoculated leaves and thus, confirming Koch's postulate. Together, C. cassiicola was identified as the causative agent of a leaf spot in C. benghalensis, which is the first record from the Philippines, and was pathogenic to tomato. The fungus' survival in C. benghalensis, an invasive weed, poses a problem to nearby crops on the next cropping season. Hence, the removal of this weed is important in reducing the source of inoculum in the field. It would be worthwhile to further study other potential plant hosts of C. benghalensis in the Philippines and select for resistance to target leaf spot in tomato cultivars and breeding lines. [ABSTRACT FROM AUTHOR]

As the number of livestock increased in the years following English colonisation of Australia in 1788, the need for nutritious fodder, including lucerne (Medicago sativa), grew. One of the first diseases found on lucerne was a leaf spot which was collected in 1879 by George Bancroft, a physician and naturalist, in a suburb of Brisbane. The Queensland Government Botanist Frederick Manson Bailey sent a specimen to the prominent English mycologists Miles Joseph Berkeley and Christopher Edmund Broome who in 1883 formally described and named the fungus Sphaerella destructiva. That fungus is now known as Pseudopeziza medicaginis , the causal agent of common leaf spot of lucerne. It was one of over 300 fungi that were included in a 1880 paper co-written by the Reverend Julian Tenison-Woods and Frederick Bailey. At that time almost all of these fungi which had been collected in Australia were identified by overseas mycologists, particularly Berkeley and Broome. It can be argued that their 1880 paper was the first significant one published in Australia which focussed on fungi. Just a decade or so later Australian scientists, in particular Daniel McAlpine, were describing new fungal taxa on their own. Among the fungi recorded in a paper published in the 1880 Proceedings of the Linnaean Society of New South Wales was Sphaerella destructiva , now Pseudopeziza medicaginis , the cause of common leaf spot of lucerne. The paper, co-authored by the naturalist Reverend Julian Tenison-Woods and the Queensland Government Botanist Frederick Manson Bailey was the first known comprehensive list of Australian fungi published by Australian residents. It is a milestone in the evolution of mycology and plant pathology studies in Australia. Photograph by H. H. Baily. [ABSTRACT FROM AUTHOR]

Crop diseases significantly impact crop yields, and promoting specialized control of crop diseases is crucial for ensuring agricultural production stability. Disease identification primarily relies on human visual inspection, which is inefficient, inaccurate, and subjective. This study focused on the plum red spot (Polystigma rubrum), proposing a two-stage detection algorithm based on deep learning and assessing the severity of the disease through lesion coverage rate. The specific contributions are as follows: We utilized the object detection model YOLOv8 to strip leaves to eliminate the influence of complex backgrounds. We used an improved U-Net network to segment leaves and lesions. We combined Dice Loss with Focal Loss to address the poor training performance due to the pixel ratio imbalance between leaves and disease spots. For inconsistencies in the size and shape of leaves and lesions, we utilized ODConv and MSCA so that the model could focus on features at different scales. After verification, the accuracy rate of leaf recognition is 95.3%, and the mIoU, mPA, mPrecision, and mRecall of the leaf disease segmentation model are 90.93%, 95.21%, 95.17%, and 95.21%, respectively. This research provides an effective solution for the detection and severity assessment of plum leaf red spot disease under complex backgrounds. [ABSTRACT FROM AUTHOR]

Automatic detection of tomato leaf spot disease is essential for control and loss reduction. Traditional algorithms face challenges such as large amount of data, multiple training and heavy computation. In this study, a lightweight shared Siamese neural network method was proposed for tomato leaf disease identification, which is suitable for resource‐limited environments. Experiments on Plant‐Village, Taiwan and Taiwan ++ datasets show that the accuracy fluctuates very little even when trained with only 60% of the data, which confirms the effectiveness of the proposed method in the small data environment. In addition, compared with the mainstream algorithms, it improves the accuracy by up to 35.3%on Plant‐Village and two Taiwan datasets respectively. The experimental results also show that the proposed method still performs well when the data is imbalanced and the sample size is small. [ABSTRACT FROM AUTHOR]

Tea leaf spot caused by Didymella segeticola is an important disease that threatens the healthy growth of tea plants (Camellia sinensis) and results in reductions in the productivity and quality of tea leaves. Early diagnosis of the disease is particularly important for managing the infection. Loop-mediated isothermal amplification (LAMP) assay is an efficient diagnostic technique with the advantages of simplicity, specificity, and sensitivity. In this study, we developed a rapid, visual, and high-sensitivity LAMP assay for D. segeticola detection based on sequence-characterized amplified regions. Two pairs of amplification primers (external primers F3 and B3 and internal primers FIP and BIP) were designed based on a specific sequence in D. segeticola (NCBI accession number: OR987684). Compared to common pathogens of other genera in tea plants and other species in the Didymella genus (Didymella coffeae-arabicae, Didymella pomorum, and Didymella sinensis), the LAMP method is specific for detecting the species D. segeticola. The assay was able to detect D. segeticola at a minimal concentration of 1 fg/μL genomic DNA at an optimal reaction temperature of 65 °C for 60 min. When healthy leaves were inoculated with D. segeticola in the laboratory, the LAMP method successfully detected D. segeticola in diseased tea leaves at 72 h post inoculation. The LAMP assays were negative when the DNA samples were extracted from healthy leaves. Leaf tissues with necrotic lesions from 18 germplasms of tea plants tested positive for the pathogen by the LAMP assay. In summary, this study established a specific, sensitive, and simple LAMP method to detect D. segeticola, which provides reliable technical support for estimating disease prevalence and facilitates sustainable management of tea leaf spot. [ABSTRACT FROM AUTHOR]

The basidiomycete fungus Mycena citricolor hosts on about 80 plant families. The asexual morph causes the disease known as American leaf spot of coffee (Coffea arabica). We isolated and characterized 15 isolates of M. citricolor collected from coffee plants, shade trees and weeds. Cultures on potato‐dextrose‐agar + yeast extract (PDAY) medium were kept for a week in complete darkness. The cultures were then exposed to light for 7 weeks and co‐cultivated with coffee foliar discs, to stimulate the production of gemmifers. We evaluated the speed of growth, appearance, colour of the mycelium and gemmifers production capacity. All isolates conformed to the typical cultural characteristics of M. citricolor, with beige/white thin and slightly aerial mycelium. The whitest isolate was from Persea americana, which had the slowest growth rate in vitro (6.4 mm/day), while the isolate from weed Kalanchoe pinnata was the fastest, with a speed of 9 mm/day. The most gemmifer‐producing isolates were those isolated from the coffee cultivar Catimor‐Costa Rica 95, Citharexylum donnell‐smithii and Cissus verticillata, with over 200 gemmifers per Petri dish. Isolates from Erythrina and Ipomoea nil produced <50 gemmifers on average. The Composite Aggressiveness Index (CAI) was determined on 2‐year‐old detached coffee branches of the Caturra variety foliage. The least aggressive isolate was from Erythrina poeppigiana (CAI = 0) and the most aggressive was from Kalanchoe pinnata (CAI = 18.87). The isolate from the coffee cultivar Catimor‐Costa Rica 95 was more aggressive than that from the cultivar Caturra (CAI = 9.94 vs. CAI = 3.66). Moreover, successful infection occurred only when the apex of gemmae made direct contact with the coffee leaf when using the inoculum derived from C. verticillata and Anredera cordifolia. These results show the variability in the population of the pathogen. This is the first study that characterizes the growth, morphology, reproduction and aggressiveness of M. citricolor obtained from hosts other than coffee. In addition, it is the first to report the use of coffee foliar discs to induce gemmifer production in vitro and to assess and quantify the effect of gemma position when inoculating coffee leaves. [ABSTRACT FROM AUTHOR]

Bacterial diseases cause colossal losses in vegetable crops and are considered major limiting factors for the commercial production of vegetables around the globe. Among bacterial diseases, angular leaf spot of cucumber caused by Pseudomonas syringae is one of the most economically important diseases that cause substantial economic loss to the cucumber crop. In this study, the in‐vitro and in‐vivo effects of different strains (X1–X15) of the nematode symbiotic bacterium Xenorhabdus nematophila was determined on the growth of P. syringae in different selected media (TB, SB, SOB, SOC, YT and LB) and at different pH levels (6.5, 7.5 and 8.5) and on the incidence of angular leaf spot disease on potted cucumber plants. According to the results, maximum growth inhibition of P. syringe (25 mm) was observed in the case of strain X12, followed by strains X10 (23 mm), X8 (21 mm) and X6 (20 mm), while maximum colony growth was observed in the control. Moreover, this P. syringae growth inhibition by the X12 strain of X. nematophila was significantly maximum in SB medium and at pH 7.5. Results of the in‐vivo experiment with potted plants showed a maximum incidence (90%) of angular leaf spot disease in control plants, while a minimum disease incidence (15%) was observed for the plants treated with two times dilution of X. nematophila culture, followed by ten times (23%) and fifty times (35%). The overall results of this study demonstrate the inhibitory effect of X. nematophila on the growth and incidence of P. syringae and underscore its putative role in the biological management of plant pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Cercospora leaf spot (CLS) disease is one of the most important diseases affecting sugar beet production in Egypt; caused by Cercospora beticola Sacc. The sensitivity of five beet cultivars were examined for their CLS infection: "Farida, Oscar Poly, Pleno, Arthos Poly, and Gaselle" under natural infection at Kafr-El Sheik, Egypt. Farida cv. was the most sensitive cultivar and was used for a greenhouse trial. This was conducted at the experimental Farm of the Faculty of Agriculture, Fayoum University, Fayoum, Egypt. Soil was divided into two parts, the 1st part was treated by potassium humate (KH) addition, while the other part had no KH treatments. However, sugar beet plants within the two soil parts were treated with foliar application included ten treatments of four different induced resistant chemicals; zinc-sulphate (ZnS-1 and ZnS-2), ammonium-molybdate (AmMo-1 and AmMo-2), salicylic-acid (SA-1 and SA-2), and calciumsilicate (CaSi-1 and CaSi-2), (concentrations; 6, 12, 0.8, 1.6, 3, 6, 5, and 10 mM, respectively), and two control treatments; fungicide (0.5 m/L) and negative control. All the chemical inducers treatments had recorded a significant decrease in disease severity and incidence (DS and DI) compared to negative control. Fungicide recorded the highest decrease in DS and DI, 7.33 and 23.33, respectively. Followed by CaSi-2, AmMo-2, and SA-2 treatments, where DS estimated data were 11.33, 12, and 13.33%, respectively. No significant differences were observed in growth parameters within foliar and soil treatments. CaSi-1 and fungicide treatments showed the most significant increases in extractable sugar. CaSi, AmMo, and SA treatments could be alternatives to fungicide managing CLS. [ABSTRACT FROM AUTHOR]

The European Commission requested the EFSA Panel on Plant Health to conduct a pest categorisation of Coniella castaneicola (Ellis & Everh) Sutton, following commodity risk assessments of Acer campestre, A. palmatum, A. platanoides, A. pseudoplatanus, Quercus petraea and Q. robur plants from the UK, in which C. castaneicola was identified as a pest of possible concern to the EU. When first described, Coniella castaneicola was a clearly defined fungus of the family Schizoparmaceae, but due to lack of a curated type‐derived DNA sequence, current identification based only on DNA sequence is uncertain and taxa previously reported to be this fungus based on molecular identification must be confirmed. The uncertainty on the reported identification of this species translates into uncertainty on all the sections of this categorisation. The fungus has been reported on several plant species associated with leaf spots, leaf blights and fruit rots, and as an endophyte in asymptomatic plants. The species is reported from North and South America, Africa, Asia, non‐EU Europe and Oceania. Coniella castaneicola is not known to occur in the EU. However, there is a key uncertainty on its presence and geographical distribution worldwide and in the EU due to its endophytic nature, the lack of systematic surveys and possible misidentifications. Coniella castaneicola is not included in Commission Implementing Regulation (EU) 2019/2072 and there are no interceptions in the EU. Plants for planting, fresh fruits and soil and other growing media associated with infected plant debris are the main pathways for its entry into the EU. Host availability and climate suitability in parts of the EU are favourable for the establishment and spread of the fungus. Based on the scarce information available, the introduction and spread of C. castaneicola in the EU is not expected to cause substantial impacts, with a key uncertainty. Phytosanitary measures are available to prevent its introduction and spread in the EU. Because of lack of documented impacts, Coniella castaneicola does not satisfy all the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest. [ABSTRACT FROM AUTHOR]

In the Mediterranean Basin, the pistachio crop is considered an emerging nut crop due to the dependence of the European nut markets on international imports. Consequently, the extension and intensification of pistachio production to nontraditional growing areas has promoted both classic and emerging diseases of this nut tree, which are limiting factors in crop production. Due to the limited interest in pistachio crops, the aetiology and epidemiology of the main pistachio diseases are poorly studied. Thus, this review summarizes the state of pistachio disease research, with particular attention given to the Mediterranean area. The information reported here is based not only on the literature, but also the advancement of our research on pistachio diseases conducted in both Italy and Spain. We describe the main fungal diseases of the tree canopy in Mediterranean countries, such as Botryosphaeria panicle and shoot blight, Septoria leaf spot, and stem, branch and trunk canker diseases, followed by the main soilborne diseases. In addition, we review minor and/or sporadic fungal diseases originating in not only the Mediterranean, but also other pistachio‐producing countries. Another section is dedicated to other diseases caused by bacteria, phytoplasmas, viruses and nematodes. Finally, we summarize the main control strategies adopted in Mediterranean Basin countries against pistachio diseases. [ABSTRACT FROM AUTHOR]

The fungal pathogen Calonectria pseudonaviculata causes boxwood blight and is a significant threat to the boxwood industry, as well as historic boxwood gardens. The pathogen produces conidia in sticky masses that are splash dispersed, which germinate and infect through stomata on the leaves or stems, causing leaf spots and stem lesions. Despite its ability to cause severe infections on boxwood plants, the pathogen often has a low germination rate on artificial media under lab conditions. To identify cues that stimulate germination, we explored whether host factors could induce high germination rates. In this study, we demonstrate that C. pseudonaviculata spores achieve high germination rales when they are placed on detached leaves of boxwood and other known hosts, compared to potato dextrose agar and glass coverslips. We also demonstrate that gennination is induced by volatiles from detached leaves of boxwood, as well as the nonhost Berberis tlumbergii. When C. pseudonaviculata spores were exposed to volatiles from boxwood leaves in the presence of ethylene scrubber packs that contained potassium permanganate, the stimulatory effect on spore germination was reduced. However, ethylene, a regulator of leaf senescence, did not stimulate germination of C. pseudonaviculata spores. This suggests that the pathogen may have evolved to recognize one or more host volatiles, other than ethylene to induce germination, thus limiting its growth until it senses the presence of a host plant. [ABSTRACT FROM AUTHOR]

Crop diseases pose significant threats to agriculture, impacting crop production. Biotic factors contribute to various diseases, including fungal, bacterial, and viral infections. Recent advancements in deep learning present a novel approach to the detection and recognition of these crop diseases. While considerable research has focused on identifying and recognizing crop diseases, fungal disease-affected crops have received relatively less attention and also detecting disease on different region datasets. This paper is about spotting fungal diseases in crops across different regions with diverse climates. It emphasizes the need for tailored detection methods, addressing the risk of mycotoxin production by fungi, which can harm both humans and animals. Detecting fungal diseases in apple, guava, and custard apple crops such as spot, scab, rust, rot, leaf spot, and insect ate. In the proposed work, the modified ResNeXt variant of the convolution neural network (CNN) technique was employed to predict 3 major crop classes of fungal disease. Initially, using Inception-v7 and ResNet for fungal disease in crops did not yield satisfactory results. A modified ResNeXt CNN model was proposed, showing improved fungal disease prediction. The novel model underwent a comparison with established methodologies. The suggested model draws upon a benchmark dataset consisting of 14,408 images capturing fungal diseases, categorized into three distinct classes: apple, custard apple, and guava. Experimental outcomes show that the proposed mutated ResNeXt model outperformed the state-of-the-art approaches. The model achieved 98.92% accuracy and high performance across recall, precision, and F1-score (above 99%) for the benchmark dataset, which gained encouragement and was comparable with the state-of-the-art approach. [ABSTRACT FROM AUTHOR]

Alfalfa spring black stem and leaf spot disease (ASBS) is a cosmopolitan soil-borne and seed-borne disease caused by Phoma medicaginis, which adversely affects the yield, and nutritive value and can stimulate production of phyto-oestrogenic compounds at levels that may adversely affect ovulation rates in animals. This review summarizes the host range, damage, and symptoms of this disease, and general features of the infection cycle, epidemic occurrence, and disease management. ASBS has been reported from over 40 countries, and often causes severe yield loss. Under greenhouse conditions, reported yield loss was 31–82% for roots, 32–80% for leaves, 21% for stems and 26–28% for seedlings. In field conditions, the forage yield loss is up to 56%, indicating that a single-cut yield of 5302 kg/ha would be reduced to 2347 kg/ha. P. medicaginis can infect up to 50 species of plants, including the genera Medicago, Trifolium, Melilotus, and Vicia. ASBS is more severe during warm spring conditions before the first harvest than in hot summer and cooler winter conditions, and can infect alfalfa roots, stems, leaves, flowers, pods, and seeds, with leaf spot and/or black stem being the most typical symptoms. The primary infection is caused by the overwintering spores and mycelia in the soil, and on seeds and the cortex of dead and dry stems. The use of resistant cultivars is the most economical and effective strategy for the control of ASBS. Although biological control has been studied in the glasshouse and is promising, chemical control is the main control method in agriculture. [ABSTRACT FROM AUTHOR]

Introduction: Precise semantic segmentation of microbial alterations is paramount for their evaluation and treatment. This study focuses on harnessing the SegFormer segmentation model for precise semantic segmentation of strawberry diseases, aiming to improve disease detection accuracy under natural acquisition conditions. Methods: Three distinct Mix Transformer encoders - MiT-B0, MiT-B3, and MiTB5 - were thoroughly analyzed to enhance disease detection, targeting diseases such as Angular leaf spot, Anthracnose rot, Blossom blight, Gray mold, Leaf spot, Powdery mildew on fruit, and Powdery mildew on leaves. The dataset consisted of 2,450 raw images, expanded to 4,574 augmented images. The Segment Anything Model integrated into the Roboflow annotation tool facilitated efficient annotation and dataset preparation. Results: The results reveal that MiT-B0 demonstrates balanced but slightly overfitting behavior, MiT-B3 adapts rapidly with consistent training and validation performance, and MiT-B5 offers efficient learning with occasional fluctuations, providing robust performance. MiT-B3 and MiT-B5 consistently outperformed MiT-B0 across disease types, with MiT-B5 achieving the most precise segmentation in general. Discussion: The findings provide key insights for researchers to select the most suitable encoder for disease detection applications, propelling the field forward for further investigation. The success in strawberry disease analysis suggests potential for extending this approach to other crops and diseases, paving the way for future research and interdisciplinary collaboration. [ABSTRACT FROM AUTHOR]

Introduction: Sodium pheophorbide a (SPA) is a natural plant-derived photosensitizer, with high photoactivated antifungal activity against some phytopathogenic fungi. However, its fungicidal effect on Diaporthe mahothocarpus, a novel pathogen that causes Camellia oleifera leaf spot blight, is unclear. Methods: In the present study, we explored its inhibitory effects on spore germination and mycelial growth of D. mahothocarpus. Then we determined its effects on the cell membrane, mycelial morphology, redox homeostasis, and cell death through bioassay. Finally, RNA-seq was used further to elucidate its mode of action at the transcriptional level. Results: We found that SPA effectively inhibited the growth of D. mahothocarpus, with half-maximal effective concentrations to inhibit mycelial growth and spore germination of 1.059 and 2.287 mg/mL, respectively. After 1.0 mg/mL SPA treatment, the conductivity and malondialdehyde content of D. mahothocarpus were significantly increased. Scanning electron microscopy and transmission electron microscopy indicated that SPA significantly affected the morphology and ultrastructure of D. mahothocarpus hyphae, revealing that SPA can destroy the mycelial morphology and cell structure, especially the cell membrane of D. mahothocarpus. Furthermore, transcriptome analysis revealed that SPA significantly suppressed the expression of genes involved in morphology, cell membrane permeability, and oxidative stress. Then, we also found that SPA significantly promoted the accumulation of reactive oxygen species (ROS) in of D. mahothocarpus, while it decreased the content of reduced glutathione, inhibited the enzyme activities of superoxide dismutase and catalase, and exacerbated DNA damage. Annexin V-FITC/PI staining also confirmed that 1.0 mg/mL SPA could significantly induce apoptosis and necrosis. Discussion: Generally, SPA can induce ROS-mediated oxidative stress and cell death, thus destroying the cell membrane and hyphal morphology, and ultimately inhibiting mycelial growth, which indicates that SPA has multiple modes of action, providing a scientific basis for the use of SPA as an alternative plant-derived photoactivated fungicide against C. oleifera leaf spot blight. [ABSTRACT FROM AUTHOR]

Septoria pistaciarum, a causal agent of Septoria leaf spot disease of pistachio, is a fungal pathogen that causes substantial losses in the cultivation, worldwide. This study describes the first pan-genome-based survey of this phytopathogen— comprising a total of 27 isolates, with 9 isolates each from 3 regional units of Greece (Pieria, Larissa and Fthiotida). The reference isolate (SPF8) assembled into a total of 43.1  Mb, with 38.6% contained within AT-rich regions of approximately 37.5% G:C. The genomes of the 27 isolates exhibited on average 42% gene-coding and 20% repetitive regions. The genomes of isolates from the southern Fthiotida region appeared to more diverged from each other than the other regions based on SNP-derived trees, and also contained isolates similar to both the Pieria and Larissa regions. In contrast, isolates of the Pieria and Larissa were less diverse and distinct from one another. Asexual reproduction appeared to be typical, with no MAT1-2 locus detected in any isolate. Genomebased prediction of infection mode indicated hemibiotrophic and saprotrophic adaptations, consistent with its long latent phase. Gene prediction and orthology clustering generated a pan-genome-wide gene set of 21,174 loci. A total of 59 ortholog groups were predicted to contain candidate effector proteins, with 36 (61%) of these either having homologs to known effectors from other species or could be assigned predicted functions from matches to conserved domains. Overall, effector prediction suggests that S. pistaciarum employs a combination of defensive effectors with roles in suppression of host defenses, and offensive effectors with a range of cytotoxic activities. Some effector-like ortholog groups presented as divergent versions of the same protein, suggesting region-specific adaptations may have occurred. These findings provide insights and future research directions in uncovering the pathogenesis and population dynamics of S. pistaciarum toward the efficient management of Septoria leaf spot of pistachio. [ABSTRACT FROM AUTHOR]