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BackgroundColletotrichum fungi infect a wide diversity of monocot and dicot hosts, causing diseases on almost all economically important plants worldwide. Colletotrichum is also a suitable model for studying gene family evolution on a fine scale to uncover events in the genome associated with biological changes.ResultsHere we present the genome sequences of 30 Colletotrichum species covering the diversity within the genus. Evolutionary analyses revealed that the Colletotrichum ancestor diverged in the late Cretaceous in parallel with the diversification of flowering plants. We provide evidence of independent host jumps from dicots to monocots during the evolution of Colletotrichum, coinciding with a progressive shrinking of the plant cell wall degradative arsenal and expansions in lineage-specific gene families. Comparative transcriptomics of 4 species adapted to different hosts revealed similarity in gene content but high diversity in the modulation of their transcription profiles on different plant substrates. Combining genomics and transcriptomics, we identified a set of core genes such as specific transcription factors, putatively involved in plant cell wall degradation.ConclusionsThese results indicate that the ancestral Colletotrichum were associated with dicot plants and certain branches progressively adapted to different monocot hosts, reshaping the gene content and its regulation.

Olive tree anthracnose is caused by infection with Colletotrichum fungi, which in Portugal are mostly C. nymphaeae, C. godetiae, and C. gloeosporioides s.s. Severe economic losses are caused by this disease that would benefit from a greener and more efficient alternative to the present agrochemical methods. Yeasts are serious candidates for pre-harvest/in field biocontrol of fungal infections. This work identified the yeast Wickerhamomyces anomalus as a strong antagonizer of the three fungi and studied in vitro this ability and its associated mechanisms. Antagonism was shown to not depend on the secretion of volatile compounds (VOCs), or siderophores or any other agar-diffusible compound, including hydrolytic enzymes. Rather, it occurred mostly in a cell-to-cell contact dependent manner. This was devised through detailed microscopic assessment of yeast-fungus cocultures. This showed that W. anomalus antagonism of the three Colletotrichum proceeded through (i) the adhesion of yeast cells to the phytopathogen hyphae, (ii) the secretion of a viscous extracellular matrix, and (iii) the emptying of the hyphae. Yeasts ultimately putatively feed on hyphal contents, which is supported by light microscopy observation of MB and PI co-culture-stained samples. Accordingly, numerous W. anomalus cells were observed packing inside C. godetiae emptied hyphae. This behaviour can be considered microbial predation and classified as necrotrophic mycoparasitism, more explicitly in the case of C. godetiae. The results support the prospect of future application of W. anomalus as a living biofungicide/BCA in the preharvest control of olive anthracnose. [ABSTRACT FROM AUTHOR]

Anthracnose of mango is one of the major postharvest diseases of mango fruit caused by members of the Colletotrichum gloeosporioides species complex such as Colletotrichum siamense. Crude extracts from dry trunk bark of four Cinnamomum species (C. burmanni, C. iners, C. loureiroi, and C. verum), a commercial cinnamon powder, cinnamaldehyde, eugenol, and cinnamon oil were assayed for their antifungal activity against Colletotrichum siamense. The crude extract of C. verum at 500 mg L−1 showed the highest inhibition of mycelial growth. At a concentration above 10 g L−1 cinnamaldehyde, eugenol, and cinnamon oil showed 100% mycelial inhibition. Using the microdilution assay, C. burmanni and C. verum crude extracts were effective against Colletotrichum siamense spore germination and showed a minimum inhibitory concentration (MIC) value of 625 mg L−1 while the MIC value of cinnamaldehyde was 50 mg L−1. The direct bioautography of the C. verum extract and the fractions obtained by column chromatography over silica gel against Cladosporium herbarum revealed clear inhibition zones on TLC plates. The treatment of Colletotrichum siamense spores with this active fraction led to severe membrane damage which was observed by scanning electron microscopy. Comparative HPLC analyses of the Cinnamomum extracts and the active fraction of C. verum, cinnamon power, and the cinnamaldehyde and eugenol as standards indicated cinnamaldehyde as the major compound. The C. verum fraction reduced disease severity and disease incidence on inoculated mango fruit. Moreover, uninoculated mango dipped into C. burmanni and C. verum extracts reduced the naturally occurring disease while total soluble solid, titratable acidity, and weight loss of dipped mango were insignificantly different from the untreated fruit control. [ABSTRACT FROM AUTHOR]

Introduction: Camellia anthracnose is caused by multiple Colletotrichum species, resulting in severe yield losses of oil-tea Camellia. Colletotrichum fructicola is one of the major anthracnose pathogens of oil-tea Camellia worldwide. However, developing unique molecular markers for the rapid and accurate detection of Colletotrichum fructicola from diverse Colletotrichum species, as well as early monitoring and effective control of the disease, remains largely unexplored. Methods: C. fructicola-specific genes were obtained using a BLAST search of the sequences of predicted genes in C. fructicola against the genome sequences of Colletotrichum fungal pathogens. In this study, Colletotrichum fructicola- specific molecular markers were developed for rapid and accurate detection of C. fructicola among Camellia anthracnose causing fungal pathogens. Results: Using genomic DNA-based end-point PCR and qPCR, three C. fructicola-specific genes with the ability to distinguish C. fructicola from other oil-tea Camellia anthracnose-related Colletotrichum species, including Colletotrichum camelliae, Colletotrichum gloeosporioides, and Colletotrichum siamense, and oil-tea Camellia fungal pathogens belonging to the genus Neopestalotiopsis, Pestalotiopsis, and Alternaria, were validated as molecular markers. In addition, these three molecular markers were highly sensitive to detecting C. fructicola using DNA extracted fromthe inoculated leaves of oil-tea Camellia. Discussion: These findings enable us to rapidly and uniquely detect the Camellia anthracnose disease caused by Colletotrichum fructicola, which will equip farmers with an effective tool for monitoring Camellia anthracnose disease in the field and taking timely control measurements in advance. [ABSTRACT FROM AUTHOR]

African yam bean (AYB; Sphenostylis stenocarpa) is an underutilized legume indigenous to Africa with great potential to enhance food security and offer nutritional and medicinal opportunities. However, low grain yield caused by fungal diseases, including pod blight and leaf tip dieback, deters farmers from large‐scale cultivation. To determine the prevalence of fungal diseases affecting leaves, pods and flowers of AYB, a survey was conducted in 2018 and 2019 in major AYB‐growing areas in Nigeria. Leaf tip dieback, flower bud rot and pod blight were the most common symptoms. Morphological and molecular assays were conducted to identify the causal agents of the observed diseases. In all the samples examined, fungi from eight genera were isolated from diseased leaves, buds and pods. Koch's postulates were fulfilled only for fungi belonging to the Colletotrichum genus. Fungi from the other seven genera did not produce disease symptoms in healthy AYB tissues. Several Colletotrichum isolates were characterized by sequencing the rDNA internal transcribed spacer (ITS), glyceraldehyde‐3‐phosphate dehydrogenase, calmodulin and ApMAT loci. A combined phylogenetic analysis revealed four Colletotrichum species: C. siamense, C. theobromicola and C. fructicola, which were recovered from diseased leaves, and C. truncatum, recovered from diseased pods and buds. Our results are useful to gear efforts to develop integrated management strategies to control diseases affecting AYB in Nigeria and elsewhere. Availability of such strategies may stimulate greater AYB cultivation, which can contribute to diet diversification, something repeatedly advocated by a range of stakeholders to increase food security and prosperity of smallholder farmers. [ABSTRACT FROM AUTHOR]

Anthracnose is one of the destructive diseases of pitaya that seriously affects the plant growth and fruit quality and causes significant yield and economic losses worldwide. However, information regarding the species of pathogens that cause anthracnose in pitaya (Hylocereus undatus) fruits in Gansu Province, China, and its pathogenic mechanism is unknown. Thus, the purposes of our present study were to identify the species of pathogens causing H. undatus fruits anthracnose based on the morphological and molecular characteristics and determine its pathogenic mechanism by physiological and biochemical methods. In our present study, forty-six isolates were isolated from the collected samples of diseased H. undatus fruits and classified as three types (named as H-1, H-2, and H-3), according to the colony and conidium morphological characteristics. The isolation frequencies of H-1, H-2, and H-3 types were 63.04%, 21.74%, and 15.22%, respectively. The representative single-spore isolate of HLGTJ-1 in H-1 type has significant pathogenicity, and finally we identified Colletotrichum truncatum as the pathogen based on the morphological characteristics as well as multi-locus sequence analysis. Moreover, the H. undatus fruits inoculated with C. truncatum had a significantly increased activity of cell wall-degrading enzymes (CWDEs) cellulase (Cx), β-glucosidase (β-Glu), polygalacturonase (PG), and pectin methylgalacturonase (PMG), while having a decreased level of cell wall components of original pectin and cellulose in comparison to control. The average increased activities of Cx, β-Glu, PG, and PMG were 30.73%, 40.40%, 51.55%, and 32.23% from day 0 to 6 after inoculation, respectively. In contrast, the average decreased contents of original pectin and cellulose were 1.82% and 16.47%, respectively, whereas the average increased soluble pectin content was 38.31% in comparison to control. Our results indicate that C. truncatum infection increased the activities of CWDEs in H. undatus fruits to disassemble their cell wall components, finally leading to the fruits' decay and deterioration. Thus, our findings will provide significant evidence in the controlling of pitaya anthracnose in the future. [ABSTRACT FROM AUTHOR]

Colletotrichum lini is a fungal pathogen of flax that can cause significant yield and quality losses. In this work, we obtained the first complete annotated genome assembly of the highly virulent C. lini strain #394-2. The nuclear genome consisted of ten core and two accessory chromosomes and had a length of 53.7 Mb. The mitochondrial genome was 39.1 kb. The assembly was obtained by the Canu–Racon ×2–Medaka–Polca algorithm using Oxford Nanopore Technologies and Illumina data. As a result of the annotation with the Illumina RNA-Seq data, 12,449 genes were identified. Potential signaling proteins were tested for effector functions and 550 effector proteins were predicted using EffectorP. The visualization of the effector protein localization revealed that the presence of effector proteins was associated with repeat-rich regions. A comparison of the genomic structure of C. lini with chromosome-level and complete assemblies of the genus Colletotrichum representatives revealed that the genomes of Colletotrichum species differed by the presence of chromosomal rearrangements. The obtained assembly expands the knowledge of the genomic structure of Colletotrichum species and provides the basis for further studies of C. lini, which will help to understand the virulence mechanisms and protect flax from anthracnose. [ABSTRACT FROM AUTHOR]

Crop disease often leads to field epidemics with serious threats to yield. Early symptoms are sometimes difficult to identify, so the origin of primary inoculum is a critical focal point in the study of plant diseases, as it can help design management strategies to reduce crop losses. Here, we investigated whether anthracnose of water yams (Dioscorea alata L.) caused by the species complex Colletotrichum gloeosporioides can start from infected seed tubers from the previous harvest. Over two years, we collected tubers with varying pathogen prevalence in the field directly from producers and conducted fungal isolations in the lab to sample C. gloeosporioides. We also proceeded to artificially inoculate tubers before planting and monitored disease development. Finally, we genotyped isolates from leaves in the fields and assessed fixation indices between plots based on plot ownership (plots with a common seed tuber origin from a single farmer) vs. samples in plots from unrelated producers in Guadeloupe, Martinique, and Barbados. We were unable to isolate the fungus from harvested tubers in either sampling survey nor did any plants grown from inoculated tubers develop any disease symptoms during growth. Also, the genetic structure of samples within each plot was independent of plot ownership, though this occurred with varying levels in the different islands. These results suggest that contaminated planting material from seed tubers is not the primary source of the disease, which is in contrast to the common perception of yam anthracnose prevalence in the Antilles. [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. Core Ideas: Tools for selecting resistant lines are crucial for the success in breeding programs aiming resistance.Factor analysis proved to be an alternative for accurate selection of resistant cultivars.Six cultivars were selected by factor analysis as resistant to anthracnose and angular leaf spot. [ABSTRACT FROM AUTHOR]

Anthracnose caused by Colletotrichum species is a serious disease of loquat (Eriobotrya japonica), but the species of Colletotrichum that are associated with the disease in Japan have not been adequately surveyed. In this study, 46 isolates were isolated from diseased leaves and fruits of loquat in Kagawa and Tokushima prefectures in 2017 and 2018. On the basis of morphological features and molecular approaches, seven Colletotrichum species were identified: C. fioriniae, C. nymphaeae, C. karsti, C. aenigma, C. fructicola, C. gloeosporioides s. s., and C. siamense. The most prevalent species was C. karsti (43.5% of total species), followed by C. fioriniae (21.7%) and C. gloeosporioides s. s. (13.0%). All identified species were confirmed to cause loquat anthracnose by fulfilling Koch's postulates. The loquat isolates of C. fioriniae, C. fructicola, and C. siamense also caused symptoms on all tested plants of kiwifruit, satsuma mandarin, persimmon, and peach. This report is the first on C. karsti and C. aenigma associated with loquat anthracnose and the first record of C. fructicola in Japan. [ABSTRACT FROM AUTHOR]

Pepper is a vegetable that is used and cultivated worldwide. The quality and production of pepper are reduced by fruit anthracnose disease caused by Colletotrichum scovillei. The highly conserved fungal sucrose non‐fermenting 1 (SNF1)‐related AMPK protein kinases are implicated in the pathogenicity and differentiation of several destructive foliar fungal pathogens; in addition, they affect fungal growth in the presence of glucose at different concentrations and under different environmental stresses. However, the function of SNF1 in C. scovillei is unclear. We functionally characterized SNF1 of C. scovillei using a targeted deletion mutant (ΔCssnf1) generated by homology‐dependent replacement. ΔCssnf1 was severely impaired in mycelial growth under glucose‐limited conditions; multiple defects in conidiation, conidial germination, appressorium formation, lipid degradation and vacuole formation were also observed. Compared to the wild type, ΔCssnf1 caused anthracnose disease of reduced severity on intact and wounded pepper fruits. These defects were recovered in the complemented strain (Cssnf1c). Taken together, our findings implicate CsSNF1 in the growth, development and virulence of C. scovillei. [ABSTRACT FROM AUTHOR]

In Peninsular Malaysia, Colletotrichum fioriniae, Colletotrichumfructicola, Colletotrichumscovillei, Colletotrichumsiamense and Colletotrichumtruncatum are the causative pathogens of chilli anthracnose. In the present study, the pathogenic variability and virulence levels of these five Colletotrichum spp. were evaluated. Isolates of C. fioriniae, C. fructicola, C. scovillei, C. siamense and C. truncatum were tested for pathogenicity using red and green Capsicum annuum and red and green Capsicumfrutescens. Pathogenicity tests were conducted using spore suspensions and mycelial plugs on wounded and nonwounded chilli fruits. All isolates tested on the wounded chilli fruits caused anthracnose symptoms with variable disease severity and virulence. In nonwounded chilli fruits, only isolates of C. scovillei (n = 7) and C. truncatum (n = 5) caused infection. C. fioriniae, C. fructicola, C. scovillei, C. siamense and C. truncatum showed variability in pathogenicity and virulence levels in red and green chilli fruits of Ca. annuum and Ca. frutescens. Pathogenicity tests on wounded and nonwounded chilli fruits can be used to identify pathotypes within anthracnose pathogen populations. This is important for strategizing the effective disease management of chilli anthracnose. [ABSTRACT FROM AUTHOR]

Camellia oleifera C. Abel is a woody oil crop with multiple purposes. This study aims to investigate the mutagenic effects of 60Co-γ radiation on C. oleifera seedlings and to screen anthracnose-resistant mutants. Two C. oleifera varieties were investigated: 'Xianglin 1' (XL1) and 'Xianglin 210' (XL210). Seeds were irradiated with 0 Gy, 30 Gy, 50 Gy, and 80 Gy of 60Co-γ, and after one year of planting, the mutagenic lines were studied, and disease-resistant mutants were screened. Results showed that as the radiation intensity was increased, the emergence percentage of both C. oleifera XL210 and XL1 was significantly decreased. Radiation significantly changed the SOD and POD activities in both varieties. Furthermore, 80 Gy irradiated lines showed reduced anthracnose resistance in both varieties. However, 50 Gy irradiated lines showed enhanced disease resistance in XL210 while reducing it in XL1. The 30 Gy irradiated lines did not affect the disease resistance of either variety. Colletotrichum gloeosporioides infection tests were conducted on 94 mutant C. oleifera seedlings, resulting in 8 highly resistant mutants (A3, A8, A10, A19, A21, A32, A35, B17) and 3 susceptible mutants (A4, B15, B27) in XL210 and XL1. Differences in SOD and POD activities led to variations in disease resistance among different mutants. Additionally, the expression levels of CoSOD1, CoPOD, CoIDD4, and CoWKRY78 were varied among the different mutants. This study delivers the screening of disease-resistant mutants in C. oleifera through mutagenic breeding, providing material for the development of new C. oleifera varieties and serving as a resource for further research in mutagenic breeding. [ABSTRACT FROM AUTHOR]

'Black Pearl' black bean (Phaseolus vulgaris L.) (Reg. no. CV‐362, PI 705445), developed by Michigan State University AgBioResearch, was released in 2023 as an upright, full‐season cultivar with anthracnose resistance and superior canning quality. Black Pearl was developed using pedigree breeding method to the F4 generation followed by pure line selection for disease, agronomic, and quality traits. In 5 years of field trials, Black Pearl yielded 3372 kg ha−1, flowered in 47 days, and matured in 98 days on average. Plants averaged 46 cm in height, with lodging resistance score of 1.8 and seed weight of 21.9 g 100 seed−1. Black Pearl combines high yield potential with upright architecture and full‐season maturity in a black seed type. Black Pearl has resistance to lodging and high pod placement within the plant making it suitable for direct harvest under narrow row production systems. Black Pearl is resistant to races 7 and 73 of anthracnose, resistant to Bean common mosaic virus, and has shown better resistance to Rhizoctonia root rot than other black bean cultivars. Black Pearl produces seed that meets industry standards for export and packaging and was rated the highest in canned bean color in the black bean market class. Core Ideas: Black Pearl is a high yielding black bean.Black Pearl has upright architecture suitable for direct harvest.Black Pearl is resistant to anthracnose.Black Pearl has excellent canning quality with exceptional black color retention following canning.Black Pearl has overall good disease resistance package. [ABSTRACT FROM AUTHOR]

Colletotrichum spp. is a phytopathogen causing anthracnose in a variety of tropical fruits. Strategies used to control postharvest diseases in tropical fruits typically rely on the use of synthetic fungicides, which have stimulated the emergence of resistant pathogens. Safer alternative strategies to control anthracnose in tropical fruits have been described in the literature. This review presents and discusses the main innovative interventions concerning the application of sustainable alternative strategies in the postharvest control of pathogenic Colletotrichum species in tropical fruits, with a particular emphasis on the studies published in the last 5 years. The available studies have shown the use of various methods, including physical barriers, natural antimicrobials, and biological control with antagonistic microorganisms, to reduce anthracnose lesion severity and incidence in tropical fruits. The available literature showed high inhibitory activity in vitro, reduced anthracnose incidence and lesion diameter, and total disease inhibition in tropical fruits. Most studies focused on the inhibition of Colletotrichum gloeosporioides on avocado, papaya, and mango, as well as of Colletotrichum musae on banana; however, the inhibition of other Colletotrichum species was also demonstrated. The application of emerging sustainable alternative methods, including natural antimicrobial substances, also stimulated the induction of defense systems in tropical fruits, including enzymatic activity, such as polyphenol oxidase, peroxidase, and phenylalanine ammonia‐lyase. The retrieved data helped to understand the current state of the research field and reveal new perspectives on developing efficient and sustainable intervention strategies to control pathogenic Colletotrichum species and anthracnose development in tropical fruits. [ABSTRACT FROM AUTHOR]

In warm and humid regions, the productivity of sorghum is significantly limited by the fungal hemibiotrophic pathogen Colletotrichum sublineola, the causal agent of anthracnose, a problematic disease of sorghum (Sorghum bicolor (L.) Moench) that can result in grain and biomass yield losses of up to 50%. Despite available genomic resources of both the host and fungal pathogen, the molecular basis of sorghum-C. sublineola interactions are poorly understood. By employing a dual-RNA sequencing approach, the molecular crosstalk between sorghum and C. sublineola can be elucidated. In this study, we examined the transcriptomes of four resistant sorghum accessions from the sorghum association panel (SAP) at varying time points post-infection with C. sublineola. Approximately 0.3% and 93% of the reads mapped to the genomes of C. sublineola and Sorghum bicolor, respectively. Expression profiling of in vitro versus in planta C. sublineola at 1-, 3-, and 5-days post-infection (dpi) indicated that genes encoding secreted candidate effectors, carbohydrate-active enzymes (CAZymes), and membrane transporters increased in expression during the transition from the biotrophic to the necrotrophic phase (3 dpi). The hallmark of the pathogen-associated molecular pattern (PAMP)-triggered immunity in sorghum includes the production of reactive oxygen species (ROS) and phytoalexins. The majority of effector candidates secreted by C. sublineola were predicted to be localized in the host apoplast, where they could interfere with the PAMP-triggered immunity response, specifically in the host ROS signaling pathway. The genes encoding critical molecular factors influencing pathogenicity identified in this study are a useful resource for subsequent genetic experiments aimed at validating their contributions to pathogen virulence. This comprehensive study not only provides a better understanding of the biology of C. sublineola but also supports the long-term goal of developing resistant sorghum cultivars. [ABSTRACT FROM AUTHOR]

Anthracnose (ANTH) caused by Colletotrichum lindemuthianum is a major disease of common bean (Phaseolus vulgaris L.). The genetic basis of ANTH resistance in the Middle American Diversity Panel (MDP) is unknown. The objectives of this study were to identify (1) Middle American accessions resistant to races 7, 19, 51, 63, 167, and 1085 of C. lindemuthianum and (ii) genomic regions and positional candidate genes associated with resistance to these races. The MDP composed of 240 Middle American accessions was evaluated for resistance to races 7, 19, 51, 63, 167, and 1085. The MDP was genotyped with 211,763 single nucleotide polymorphisms (SNPs), and mixed linear model analysis was conducted to identify genomic regions associated with resistance to the six races. Seven accessions were highly resistant to all six races, and these can be used as sources of resistance to improve specific market classes in the Middle American gene pool. The genomic region (385,894 bp) on chromosome Pv04 was significantly associated with resistance to race 167. Genomic regions on Pv02 (41,570,325 bp), Pv07 (24,122,343 bp), and Pv11 (51,707,917 bp) were significantly associated with resistance to race 19. Disease resistance (R) genes with the nucleotide binding‐APAF resistance protein and CED‐4 domain were identified as positional candidate genes on Pv04 and Pv11. There were no SNPs significantly associated with resistance to races 7, 51, 63, and 1085. Pyramiding the identified genomic regions on Pv04, Pv07, and Pv11 could provide durable ANTH resistance in Middle American varieties for races 19 and 167. [ABSTRACT FROM AUTHOR]

Recurrent selection is an effective and well‐known breeding method recommended for quantitative traits. However, the method has not been applied so far for traits typically controlled by numerous major loci, which is the case of resistance to anthracnose in common bean (Phaseolus vulgaris L.). In this study, we report the effectiveness of a recurrent selection program in developing common bean progenies with resistance to multiple races of Colletotrichum lindemuthianum, the causal agent of anthracnose in this crop. A total of 10 common bean lines, with distinct and complementary resistance profiles to races 65, 73, 81, and 89 of C. lindemuthianum, were intercrossed to establish a base population (Cycle 0). From Cycle 0, five iterative cycles of recombination, inoculation, and selection were carried out. Our results demonstrate that this recurrent selection approach can effectively combine resistance in common bean to different isolates from multiple races of C. lindemuthianum. A progressive increase in the number of progenies resistant to a higher number of C. lindemuthianum isolates was observed over the selection cycles. The genetic gain from CI to CV was 38.75% when the progenies were evaluated against a mixture of isolates from the four races of the pathogen. The reliance on specific genes makes race‐specific anthracnose resistance in common bean vulnerable to breakdown. By allowing optimal combinations of different anthracnose resistance genes, this dynamic recurrent selection approach is an attractive option for the development of common bean cultivars with increased stability and durability for anthracnose resistance. [ABSTRACT FROM AUTHOR]

Blueberry is an important perennial fruit crop with expanding consumption and production worldwide. Consumer demand for blueberries has grown due to the desirable flavor and numerous health benefits, and fresh market production in the U.S. has risen in turn. U.S. imports have also increased to satisfy year-round consumer demand for fresh blueberries. Pre- and post-harvest fruit diseases such as anthracnose (caused by Colletotrichum spp.) and botrytis fruit rot (caused by Botrytis spp.) have a significant impact on fruit quality and consumer acceptance. These are also among the most difficult diseases to control in the blueberry cropping system. These latent pathogens can cause significant losses both in the field, and especially during transport and marketplace storage. Although both diseases result in rotted fruit, the biology and infection strategies of the causal pathogens are very different, and the management strategies differ. Innovations for management, such as improved molecular detection assays for fungicide resistance, postharvest imaging, breeding resistant cultivars, and biopesticides have been developed for improved fruit quality. Development and integration of new strategies is critical for the long-term success of the blueberry industry. [ABSTRACT FROM AUTHOR]

Anthracnose, caused by Colletotrichum spp., is a threat to strawberry production globally. Unlike their chemical counterparts, microbial biofungicides offer a method of postharvest fungal disease control that is safe, sustainable and less affected by pathogen resistance. The present study evaluated the antifungal effects of three bacteria, Bacillus velezensis strains SH1 and SH2 and Pseudomonas azotoformans strain SH3, obtained from sheep manure compost tea. The bacteria or their cell‐free filtrates were tested against Colletotrichum acutatum and Colletotrichum gloeosporioides in bioassays and against strawberry anthracnose. In addition, precipitated or extracted extracellular fractions were tested to determine the effects on membrane permeability of Colletotrichum spp. spores. Confrontation assay results showed all bacteria inhibited mycelial growth, with B. velezensis SH1 and P. azotoformans SH3 being the most effective. All cell‐free filtrates inhibited mycelial growth with B. velezensis SH1 and SH2 resulting in the highest inhibition. The bacteria suppressed anthracnose lesions on strawberry fruit although effective treatments varied by causal mould. B. velezensis SH1 and SH2 significantly permeabilized spore membranes, indicating antibiosis as a possible mode of action. Investigation into antimicrobial compound production found various homologues of the lipopeptides fengycin, iturin and surfactin were produced by B. velezensis SH1 and SH2. Results suggest that lipopeptides produced by B. velezensis strains permeabilize Colletotrichum cell membranes, and that fengycins were the most inhibitory of the lipopeptides against Colletotrichum spp. [ABSTRACT FROM AUTHOR]

Summary. Anthracnose caused by Colletotrichum species is an important disease of strawberries (Fragaria × ananassa), but the species causing this disease in Germany have not been investigated based on modern systematics. By using multi-locus phy- logenetic analyses (ITS, act, gapdh, chs-1, his3, tub2), 58 Colletotrichum isolates from previous and recent collections, obtained mainly from fruit anthracnose of cultivated strawberries in Germany, were identified or re-identified as C. fioriniae, C. godetiae and C. nymphaeae (C. acutatum species complex) as well as C. anthrisci and C. line- ola (C. dematium complex). Colletotrichum nymphaeae was dominant; most of the iso- lates belonged to one clonal lineage that occurs on strawberries throughout Europe, the United States of America, and some African and Asian countries. One of the other two haplotypes was distantly related and only represented by recently collected mate- rial. All other species, each of one haplotype, had only been isolated once or twice from German strawberries. This is the first report of C. anthrisci in Germany and for the genus Fragaria worldwide; all the other isolated fungi are newly reported for this genus in Germany. Comparisons of morphological characteristics of the species identi- fied demonstrate that these features are of limited use for identification, even to species complex level. In pathogenicity tests, all five species caused anthracnose symptoms on ripe fruit of Fragaria × ananassa ‘Asia’. [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]

Lychee pepper spot, a field disease affecting lychee fruit skin, pedicels and petioles, is caused by Colletotrichum siamense, a fungal pathogen within the gloeosporioides species complex. Members of Colletotrichum from the gloeosporioides species complex and occasionally those from the acutatum species complex also cause postharvest anthracnose of lychee. Pepper spot was first described in Australia many years after anthracnose on lychee was first described, giving rise to the hypothesis that a novel species or strain within the gloeosporioides species complex causes pepper spot. In the present study, 19 isolates of Colletotrichum spp., collected from pepper spot and anthracnose symptoms on lychee fruit, representing 13 different genotypes across five species, were inoculated onto lychee fruit in the field or on detached fruit in the laboratory, to understand more about their pathogenic diversity. We found that symptoms were specific to genotype of the pathogen, as three genetically similar isolates of C. siamense consistently caused pepper spot and anthracnose, whilst other isolates caused anthracnose only. Cross‐inoculation studies on detached fruit of lychee, banana, avocado and mango also provided some evidence of host specialization in isolates of C. siamense infecting lychee in Australia. Our experiments provided further evidence that detached fruit assays cannot be used as a reliable proxy for field inoculation studies. This research confirms that C. siamense is a causal agent of both lychee pepper spot and lychee anthracnose in Australia, and Colletotrichum alienum and Colletotrichum queenslandicum are reported as causal agents of anthracnose of lychee for the first time. [ABSTRACT FROM AUTHOR]

Chili peppers were treated with gamma irradiation to develop anthracnose disease resistance. Seeds of chili peppers were irradiated with gamma rays at 0, 100, 200, 300, 400 and 500 Gy to determine the optimal dose for mutation breeding. The LD50 value was calculated to be 264.83 Gy. The 300 Gy gammairradiated chili pepper seeds (Capsicum annuum L.) were planted in the experiment field at Nan Agricultural Research and Development Center, Thailand for mutation selection. The results showed that the irradiated chili plants not only survived the anthracnose infection but also produced fruits. These fruits were less affected or unaffected by the anthracnose disease compared to the control group (unirradiated) which showed damages on every part of chili plant. The 28 healthy chili pepper plants in M3 generation that showed anthracnose resistant traits were selected as seeds for M4 generation. Two chili pepper lines in M4 generation exhibited the highest resistance to anthracnose. From the pathogenicity test, those 2 chili pepper lines were found to have resistance to anthracnose disease caused by both Colletotrichum gloeosporioides and Colletotrichum capsici. [ABSTRACT FROM AUTHOR]

Olive anthracnose outbreaks caused by the Colletotrichum species complex in the Mediterranean region decrease both fruit yield and olive oil production while also drastically degrading olive oil quality. The presence of various Colletotrichum species able to produce disease symptoms in olive fruits significantly deteriorates the efforts for an efficient crop protection strategy. In this report, the major olive productive area of Peloponnese was screened for Colletotrichum species capable of generating anthracnose symptoms. Olive fruits of 12 different olive cultivars were collected from 60 groves distributed analogously in the Peloponnese. Thirty-two fungal strains isolated from asymptomatic olive drupes were identified morphologically as Colletotrichum spp. and were multilocus genetically analyzed. The 32 isolates were grouped into two primary lineages resembling the previously characterized Colletotrichum acutatum and Colletotrichum nymphaeae based on the conducted genetic analysis for five genetic loci. The virulence of 16 Colletotrichum spp. strains were evaluated in a detached fruit assay of 10 Greek olive cultivars. The results clearly suggested that fungal isolates belonging to both C. acutatum and C. nymphaeae exhibited different levels of pathogenicity in a cultivar-dependent manner. Thus, cultivars examined in terms of the % Disease Index (%DI) were divided into highly tolerant, tolerant, and susceptible, and those analyzed regarding the % Disease Severity Index (%DSI) were divided into tolerant and susceptible. Our results suggest that the Greek cultivars of Athinolia and Megaritiki are highly tolerant to the vast majority of Colletotrichum strains isolated from Peloponnesian groves and consist of a significant genetic material for the future design of crop protection programs against anthracnose breakouts. [ABSTRACT FROM AUTHOR]

Poplar (Populus L.) anthracnose is an infectious disease that seriously affects the growth and yields of poplar trees, and large-scale poplar infections have led to huge economic losses in the Chinese poplar industry. To efficiently and accurately detect poplar anthracnose for improved prevention and control, this study collected hyperspectral data from the leaves of four types of poplar trees, namely healthy trees and those with black spot disease, early-stage anthracnose, and late-stage anthracnose, and constructed a poplar anthracnose detection model based on machine learning and deep learning. We then comprehensively analyzed poplar anthracnose using advanced hyperspectral-based plant disease detection methodologies. Our research focused on establishing a detection model for poplar anthracnose based on small samples, employing the Design of Experiments (DoE)-based entropy weight method to obtain the best preprocessing combination to improve the detection model's overall performance. We also analyzed the spectral characteristics of poplar anthracnose by comparing typical feature extraction methods (principal component analysis (PCA), variable combination population analysis (VCPA), and the successive projection algorithm (SPA)) with the vegetation index (VI) method (spectral disease indices (SDIs)) for data dimensionality reduction. The results showed notable improvements in the SDI-based model, which achieved 89.86% accuracy. However, this was inferior to the model based on typical feature extraction methods. Nevertheless, it achieved 100% accuracy for early-stage anthracnose and black spot disease in a controlled environment respectively. We conclude that the SDI-based model is suitable for low-cost detection tasks and is the best poplar anthracnose detection model. These findings contribute to the timely detection of poplar growth and will greatly facilitate the forestry sector's development. [ABSTRACT FROM AUTHOR]

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Strain WZ-12, isolated from the rhizosphere soil of star anise trees, exhibits significant antifungal efficacy against a variety of fungi, including Colletotrichum horii, the pathogenic fungus responsible for anthracnose in star anise. Based on 16S rRNA gene sequencing and phylogenetic analysis, the strain was identified as a member of the Streptomyces genus. The genome of WZ-12 comprises a linear chromosome of 9,169,400 bp and a plasmid of 378,325 bp, possessing a G + C content of 71.12%. Of note, the genome encompasses 8,172 protein-coding genes, 21 rRNA genes, 74 tRNA genes, and 89 other noncoding RNA genes. The COG, Swiss-Prot, GO, KEGG, and NR databases annotated up to 79.17, 50.50, 13.17, 37.51, and 90.43% of potential genes, respectively. Remarkably, the genome hosts 175 antimicrobial resistance genes and 33 secondary metabolite gene clusters that likely contribute to the biosynthesis of diverse bioactive compounds such as antibiotics and agents with antitumor, antioxidant, immunosuppressive, anti-inflammatory, or stress tolerance properties. These findings highlight the potential of WZ-12 as a promising source of novel bioactive molecules and suggest its significant value as a resource for developing innovative antimicrobial agents. [Figure: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Despite considerable research globally on postharvest diseases of mango, virtually no work has been done to determine the occurrence of these diseases and their causal agents in Fiji. This study is the first major field and market survey of postharvest diseases of mango in Fiji. For the field survey, fruits from five local mango cultivars were harvested at each of five locations. Fruits from five imported cultivars were also harvested from one location in Nadi. For the market survey, vendors were selected at five municipal markets for fruit collection, along with ten roadside stalls. For field and market surveys, fruits were incubated at 23°C and assessed for postharvest disease (incidence and severity of body rots and stem end rots) when ripe. Isolations were made from disease lesions and fungal cultures were identified using multilocus sequence typing. High incidences of body and stem end rots were recorded across all surveys. In the field survey of local cultivars, 'Salusalu' fruits were found to have the lowest severity of body rot and stem end rot on average, while for imported cultivars, 'Nam Doc Mai' had the lowest average severity of these diseases. The market survey showed that 'Salusalu' had a lower incidence of anthracnose on the body of fruit compared to all other cultivars, although it did have a surprisingly high incidence of stem end rot at some localities. Fungal isolates from anthracnose lesions in the field and market surveys were identified as Colletotrichum asianum, C. simmondsii and C. fructicola. C. asianum was the predominant species associated with anthracnose symptoms, accounting for 97% of isolations. Lasiodiplodia theobromae and Neofusicoccum parvum were the predominant species found in association with mango stem end rot symptoms. Other species isolated from mango stem end rot in lesser numbers included L. brasiliensis, N. umdonicola and N. kwambonambiense. All of these fungi represent new reports for Fiji. [ABSTRACT FROM AUTHOR]

Crop disease often leads to field epidemics with serious threats to yield. Early symptoms are sometimes difficult to identify, so the origin of primary inoculum is a critical focal point in the study of plant diseases, as it can help design management strategies to reduce crop losses. Here, we investigated whether anthracnose of water yams (Dioscorea alata L.) caused by the species complex Colletotrichum gloeosporioides can start from infected seed tubers from the previous harvest. Over two years, we collected tubers with varying pathogen prevalence in the field directly from producers and conducted fungal isolations in the lab to sample C. gloeosporioides. We also proceeded to artificially inoculate tubers before planting and monitored disease development. Finally, we genotyped isolates from leaves in the fields and assessed fixation indices between plots based on plot ownership (plots with a common seed tuber origin from a single farmer) vs. samples in plots from unrelated producers in Guadeloupe, Martinique, and Barbados. We were unable to isolate the fungus from harvested tubers in either sampling survey nor did any plants grown from inoculated tubers develop any disease symptoms during growth. Also, the genetic structure of samples within each plot was independent of plot ownership, though this occurred with varying levels in the different islands. These results suggest that contaminated planting material from seed tubers is not the primary source of the disease, which is in contrast to the common perception of yam anthracnose prevalence in the Antilles.

Abstract Background Sorghum anthracnose is a major disease that hampers the productivity of the crop globally. The disease is caused by the hemibiotrophic fungal pathogen Colletotrichum sublineola. The identification of anthracnose-resistant sorghum genotypes, defining resistance loci and the underlying genes, and their introgression into adapted cultivars are crucial for enhancing productivity. In this study, we conducted field experiments on 358 diverse accessions of Ethiopian sorghum. Quantitative resistance to anthracnose was evaluated at locations characterized by a heavy natural infestation that is suitable for disease resistance screening. Results The field-based screening identified 53 accessions that were resistant across locations, while 213 accessions exhibited variable resistance against local pathotypes. Genome-wide association analysis (GWAS) was performed using disease response scores on 329 accessions and 83,861 single nucleotide polymorphisms (SNPs) generated through genotyping-by-sequencing (GBS). We identified 38 loci significantly associated with anthracnose resistance. Interestingly, a subset of these loci harbor genes encoding receptor-like kinases (RLK), nucleotide-binding leucine-rich repeats (NLRs), stress-induced antifungal tyrosine kinase that have been previously implicated in disease resistance. A SNP on chromosome 4 (S04_66140995) and two SNPs on chromosome 2 (S02_75784037, S02_2031925), localized with-in the coding region of genes that encode a putative stress-induced antifungal kinase, an F-Box protein, and Xa21-binding RLK that were strongly associated with anthracnose resistance. We also identified highly significant associations between anthracnose resistance and three SNPs linked to genes (Sobic.002G058400, Sobic.008G156600, Sobic.005G033400) encoding an orthologue of the widely known NLR protein (RPM1), Leucine Rich Repeat family protein, and Heavy Metal Associated domain-containing protein, respectively. Other SNPs linked to predicted immune response genes were also significantly associated with anthracnose resistance. Conclusions The sorghum germplasm collections used in the present study are genetically diverse. They harbor potentially useful, yet undiscovered, alleles for anthracnose resistance. This is supported by the identification of novel loci that are enriched for disease resistance regulators such as NLRs, LRKs, Xa21-binding LRK, and antifungal proteins. The genotypic data available for these accessions offer a valuable resource for sorghum breeders to effectively improve the crop. The genomic regions and candidate genes identified can be used to design markers for molecular breeding of sorghum diseases resistance.

Abstract Background Disease can drastically impair common bean (Phaseolus vulgaris L.) production. Anthracnose, caused by the fungal pathogen Colletotrichum lindemuthianum (Sacc. and Magnus) Briosi and Cavara, is one of the diseases that are widespread and cause serious economic loss in common bean. Results Transcriptome analysis of the early response of common bean to anthracnose was performed using two resistant genotypes, Hongyundou and Honghuayundou, and one susceptible genotype, Jingdou. A total of 9,825 differentially expressed genes (DEGs) responding to pathogen infection and anthracnose resistance were identified by differential expression analysis. By using weighted gene coexpression network analysis (WGCNA), 2,051 DEGs were found to be associated with two resistance-related modules. Among them, 463 DEGs related to anthracnose resistance were considered resistance-related candidate genes. Nineteen candidate genes were coexpressed with three resistance genes, Phvul.001G243600, Phvul.001G243700 and Phvul.001G243800. To further identify resistance genes, 46 candidate genes were selected for experimental validation using salicylic acid (SA) and methyl jasmonate (MeJA). The results indicated that 38 candidate genes that responded to SA/MeJA treatment may be involved in anthracnose resistance in common bean. Conclusions This study identified 38 resistance-related candidate genes involved in the early response of common bean, and 19 resistance-related candidate genes were coexpressed with anthracnose resistance genes. This study identified putative resistance genes for further resistance genetic investigation and provides an important reference for anthracnose resistance breeding in common bean.

Anthracnose caused by Colletotrichum lindemuthianum is one of the main diseases that affect the bean crop. The use of semisynthetic compounds for controlling anthracnose aims at providing a higher balance to the ecosystem and a lower environmental impact. Based on this context, the objective of this work was: a) to carry out the prospection of compounds such as Phenyl S Citral, Phenyl Se Citronellal, and Citral at concentrations of 1, 0.5, 0.25, 0.125, 0.0625, 0.0312, 0.0156, 0.0078, and 0.0039%, which were modified from the essential oil of citronella and lemongrass, for controlling C. lindemuthianum; b) to evaluate the initial performance of seedlings and treat the incidence of C. lindemuthianum in bean seeds with Phenyl S Citral and Phenyl Se Citronellal at concentrations of 0.125 and 0.0625%. Phenyl Se Citronellal at 0.5% controlled 100% of mycelial growth and Phenyl S Citral at 0.5 and 1% controlled more than 50% of mycelial growth of C. lindemuthianum. The treatment with Phenyl S Citral and Phenyl Se Citronellal did not affect the physiological quality of bean seeds while increasing seedling development when using the 0.0625% concentration of Phenyl Se Citronellal. Treatment with Phenyl Se Citronellal at both concentrations decreased the incidence of C. lindemuthianum infection.

ObjectiveCamellia oleifera is one of the four major woody oil plants in the world. Diseases is a significant factor leading to the decline in quality of Camellia oleifera and the financial loss of farmers. Among these diseases, anthracnose is a common and severe disease in Camellia oleifera forests, directly impacting yields and production rates. Accurate disease assessment can improve the prevention and control efficiency and safeguarding the farmers' profit. In this study, an improved You Only Look at CoefficienTs (YOLACT) based method was proposed to realize automatic and efficient grading of the severity of Camellia oleifera leaf anthracnose.MethodsHigh-resolution images of Camellia oleifera anthracnose leaves were collected using a smartphone at the National Camellia oleifera Seed Base of Jiangxi Academy of Forestry, and finally 975 valid images were retained after a rigorous screening process. Five data enhancement means were applied, and a data set of 5 850 images was constructed finally, which was divided into training, validation, and test sets in a ratio of 7:2:1. For model selection, the Camellia-YOLACT model was proposed based on the YOLACT instance segmentation model, and by introducing improvements such as Swin-Transformer, weighted bi-directional feature pyramid network, and HardSwish activation function. The Swin Transformer was utilized for feature extraction in the backbone network part of YOLACT, leveraging the global receptive field and shift window properties of the self-attention mechanism in the Transformer architecture to enhance feature extraction capabilities. Additionally, a weighted bidirectional feature pyramid network was introduced to fuse feature information from different scales to improve the detection ability of the model for objects at different scales, thereby improving the detection accuracy. Furthermore, to increase the the model's robustness against the noise in the input data, the HardSwish activation function with stronger nonlinear capability was adopted to replace the ReLu activation function of the original model. Since images in natural environments usually have complex background and foreground information, the robustness of HardSwish helped the model better handling these situations and further improving the detection accuracy. With the above improvements, the Camellia-YOLACT model was constructed and experimentally validated by testing the Camellia oleifera anthracnose leaf image dataset.Results and DiscussionsA transfer learning approach was used for experimental validation on the Camellia oleifera anthracnose severity grading dataset, and the results of the ablation experiments showed that the mAP75 of Camellia-YOLACT proposed in this study was 86.8%, mAPall was 78.3%, mAR was 91.6% which were 5.7%, 2.5% and 7.9% higher than YOLACT model. In the comparison experiments, Camellia-YOLACT performed better than Segmenting Objects by Locations (SOLO) in terms of both accuracy and speed, and its detection speed was doubled compared to Mask R-CNN algorithm. Therefore, the Camellia-YOLACT algorithm was suitable in Camellia oleifera gardens for anthracnose real-time segmentation. In order to verify the outdoors detection performance of Camellia-YOLACT model, 36 groups of Camellia oleifera anthracnose grading experiments were conducted. Experimental results showed that the grading correctness of Camellia oleifera anthracnose injection severity reached 94.4%, and the average absolute error of K-value was 1.09%. Therefore, the Camellia-YOLACT model proposed in this study has a better performance on the grading of the severity of Camellia oleifera anthracnose.ConclusionsThe Camellia-YOLACT model proposed got high accuracy in leaf and anthracnose segmentation of Camellia oleifera, on the basis of which it can realize automatic grading of the severity of Camellia oleifera anthracnose. This research could provide technical support for the precise control of Camellia oleifera diseases.

Colletotrichum tabacum, causing anthracnose in tobacco, is a notorious plant pathogen threatening tobacco production globally. The underlying mechanisms of C. tabacum effectors that interfere with plant defense are not well known. Here, we identified a novel effector, Cte1, from C. tabacum, and its expression was upregulated in the biotrophic stage. We found that Cte1 depresses plant cell death initiated by BAX and inhibits reactive oxygen species (ROS) bursts triggered by flg22 and chitin in Nicotiana benthamiana. The CTE1 knockout mutants decrease the virulence of C. tabacum to N. benthamiana, and the Cte1 transgenic N. benthamiana increase susceptibility to C. tabacum, verifying that Cte1 is involved in the pathogenicity of C. tabacum. We demonstrated that Cte1 interacted with NbCPR1, a Constitutive expresser of Plant Resistance (CPR) protein in plants. Silencing of NbCPR1 expression attenuated the infection of C. tabacum, indicating that NbCPR1 negatively regulates plant immune responses. Cte1 stabilizes NbCPR1 in N. benthamiana. Our study shows that Cte1 suppresses plant immunity to facilitate C. tabacum infection by intervening in the native function of NbCPR1. [Graphic: 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.

Anthracnose disease (Colletotrichum spp.) in chili can lead to low fruit quantity and quality from planting to the postharvest stage. The environmentally friendly management using chitosan (CS) is expected to suppress anthracnose disease and increase the shelf-life of chili. This study aimed to determine the effect of the chitosan-tripolyphosphate (CS-TPP) to suppress anthracnose on chili during postharvest storage through in-vitro and in-vivo assays. In the in-vitro assay, CS-TPP solution with a ratio of [5:2] and [3:1] was applied into a warm Potato Dextrose Agar (PDA) medium. It was grown by Colletotrichum pathogen, while on in vivo assay, CS-TPP was applied to chili fruit before being inoculated by the pathogen. A control treatment was prepared without CS-TPP application. Results revealed that the CS-TPP ratios affected the growth of Colletotrichum spp. at the in-vitro assay. The CS-TPP [5:2] ratio was more effective than CS-TPP [3:1] in reducing the growth of Colletotrichum spp. with the fungal inhibition of 62,65% and 55,56%, respectively, compared to the control treatment. Moreover, it also showed anthracnose disease suppression on chili fruit of 51%, and 29%, respectively, compared to control treatment at in-vivo assay. This study showed the potential use of CS-TPP as a coating application for anthracnose disease management on storage chili, however further study such as viability and longevity of formula need to be done.

Background: Sorghum anthracnose is a major disease that hampers the productivity of the crop globally. The disease is caused by the hemibiotrophic fungal pathogen Colletotrichum sublineola. The identification of anthracnose-resistant sorghum genotypes, defining resistance loci and the underlying genes, and their introgression into adapted cultivars are crucial for enhancing productivity. In this study, we conducted field experiments on 358 diverse accessions of Ethiopian sorghum. Quantitative resistance to anthracnose was evaluated at locations characterized by a heavy natural infestation that is suitable for disease resistance screening. Results: The field-based screening identified 53 accessions that were resistant across locations, while 213 accessions exhibited variable resistance against local pathotypes. Genome-wide association analysis (GWAS) was performed using disease response scores on 329 accessions and 83,861 single nucleotide polymorphisms (SNPs) generated through genotyping-by-sequencing (GBS). We identified 38 loci significantly associated with anthracnose resistance. Interestingly, a subset of these loci harbor genes encoding receptor-like kinases (RLK), nucleotide-binding leucine-rich repeats (NLRs), stress-induced antifungal tyrosine kinase that have been previously implicated in disease resistance. A SNP on chromosome 4 (S04_66140995) and two SNPs on chromosome 2 (S02_75784037, S02_2031925), localized with-in the coding region of genes that encode a putative stress-induced antifungal kinase, an F-Box protein, and Xa21-binding RLK that were strongly associated with anthracnose resistance. We also identified highly significant associations between anthracnose resistance and three SNPs linked to genes (Sobic.002G058400, Sobic.008G156600, Sobic.005G033400) encoding an orthologue of the widely known NLR protein (RPM1), Leucine Rich Repeat family protein, and Heavy Metal Associated domain-containing protein, respectively. Other SNPs linked to predicted immune response genes were also significantly associated with anthracnose resistance. Conclusions: The sorghum germplasm collections used in the present study are genetically diverse. They harbor potentially useful, yet undiscovered, alleles for anthracnose resistance. This is supported by the identification of novel loci that are enriched for disease resistance regulators such as NLRs, LRKs, Xa21-binding LRK, and antifungal proteins. The genotypic data available for these accessions offer a valuable resource for sorghum breeders to effectively improve the crop. The genomic regions and candidate genes identified can be used to design markers for molecular breeding of sorghum diseases resistance. [ABSTRACT FROM AUTHOR]

The Malayan apple is a tropical fruit known by various names, such as red guava and Malay rose apple. Originating in Southeast Asia, it has shifted from being an ornamental tree to being cultivated in India to meet global demand. Well-known for its health benefits, the fruit is rich in vitamins, minerals, and antioxidants. In May 2023, Malayan apple trees in Karnataka, India, displayed anthracnose symptoms, with a 20–25% disease incidence. The fungus C. nymphaeae was isolated, identified, and confirmed through multigene phylogeny. Its pathogenicity was validated by artificially infecting Malayan fruits, causing anthracnose symptoms and fulfilling Koch's postulates. This represents the initial documented occurrence of C. nymphaeae causing anthracnose in the Malayan apple in India and the world, emphasizing the significance of this research in disease management. [ABSTRACT FROM AUTHOR]

Anthracnose is a fungal disease caused by Colletotrichum spp. that affects the avocado (Persea americana Mill.) crop and causes significant economic losses in the farming sector. To focus control measures, it is important to understand the spatial distribution and the dynamics followed by the disease under field conditions. The use of methods derived from spatial statistics facilitates this task. The aim of this study was to determine the spatial behavior of anthracnose in Persea americana Mill. cv. Hass in Donato Guerra, a municipality in the State of Mexico, Mexico, using a geostatistical and spatial analysis by distance indices. Four hundred trees were selected and georeferenced in the municipal area. In order to measure the incidence, 48 fruits were selected from every tree. Using these data, the experimental semivariogram was estimated, and adjustments were made to models that explain the spatial arrangement. Maps were created using ordinary kriging, and the infection area was estimated. The maps generated show the presence of aggregation centers and a spatial distribution mostly fitting Gaussian and exponential models, with ranges fluctuating between 12 and 56 m, indicating spatial association between data. Likewise, the greatest percentage of infected areas was 98 %, while the lowest was 45 %. Geostatistics enables a precise understanding of the distribution patterns of diseases such as anthracnose in avocado-growing areas of the State of Mexico, which facilitates the implementation of integrated management programs with greater effectiveness. [ABSTRACT FROM AUTHOR]

Crop diseases pose a major threat to agricultural production, quality, and sustainable development, highlighting the importance of early disease risk prediction for effective disease control. Tea anthracnose can easily occur in Yunnan under high-temperature and high-humidity environments, which seriously affects the ecosystem of tea gardens. Therefore, the establishment of accurate, non-destructive, and rapid prediction models has a positive impact on the conservation of biodiversity in tea plantations. Because of the linear relationship between disease occurrence and environmental conditions, the growing environmental conditions can be effectively used to predict crop diseases. Based on the climate data collected by Internet of Things devices, this study uses LASSO-COX-NOMOGRAM to analyze the expression of tea anthracrum to different degrees through Limma difference analysis, and it combines Cox single-factor analysis to study the influence mechanism of climate and environmental change on tea anthracrum. Modeling factors were screened by LASSO regression, 10-fold cross-validation and Cox multi-factor analysis were used to establish the basis of the model, the nomogram prediction model was constructed, and a Shiny- and DynNOM-visualized prediction system was built. The experimental results showed that the AUC values of the model were 0.745 and 0.731 in the training set and 0.75 and 0.747 in the verification set, respectively, when the predicted change in tea anthracnose disease risk was greater than 30% and 60%, and the calibration curve was in good agreement with the ideal curve. The accuracy of external verification was 83.3% for predicting tea anthracnose of different degrees. At the same time, compared with the traditional prediction method, the method is not affected by the difference in leaf background, which provides research potential for early prevention and phenotypic analysis, and also provides an effective means for tea disease identification and harm analysis. [ABSTRACT FROM AUTHOR]

Monitoring genetic gain is crucial to ensure breeding programs' effectiveness and identify potential challenges and areas for their improvement. Our study provides a first overview of the trends in genetic gain for tuber yield and disease resistance traits in the IITA's (International Institute of Tropical Agriculture) yam breeding program. We used historical data (2010–2022) from multiple generations of past breeding cycles evaluated at 31 sites in the white Guinea yam (Dioscorea rotundata Poir) breeding pipeline and 28 sites in the water yam (Dioscorea alata L.) breeding pipeline of IITA and its national partners in West Africa. Our result shows positive genetic trends in fresh tuber yield while recording a gain of 1.38% or 99.17 kg ha−1 per year in the white Guinea yam and 2.18% or 252.41 kg ha−1 per year in the water yam breeding pipelines. Genetic trends for virus and anthracnose resistance were in the desired direction but negligible in white Guinea yam, while significant for virus and nonsignificant for anthracnose resistance in water yam. Our findings indicate that while the breeding program has succeeded in enhancing tuber yield, post‐harvest tuber dry matter content and disease resistance (yam mosaic virus and anthracnose) did not follow a similar trend in the material being developed. This implies that the yam breeding program needs to strike a balance between various traits, ensuring that increased yield does not come at a cost to food quality or disease resistance. Our results highlight the importance of continually monitoring and assessing the performance of a breeding program and making informed decisions about which traits to focus on for future improvement. Core Ideas: Periodic monitoring of genetic gain is crucial to making informed decisions about which traits to focus on.Yam breeding program needs to strike a balance between various traits for ensuring sustained genetic gain.High‐quality historical trial data crucial for assessing genetic gain trends in breeding programs. [ABSTRACT FROM AUTHOR]

Wild crop germplasm and landrace varieties have long been considered as a source of novel genetic variation for improving domesticated crops. Due to genetic bottlenecks that occurred during domestication, dissemination, and subsequent crop improvement, many beneficial genes are absent from commercial varieties and elite breeding germplasm, yet are still present in wild populations. To catalog potential novel disease resistance genes useful for breeding more resilient dry beans, we screened wild and landrace Phaseolus vulgaris L. accessions archived in the USDA GRIN seed bank for untapped resistance to anthracnose (Colletotrichum lindemuthianum) and bean common mosaic necrosis virus (BCMNV). A population of 194 wild and 55 landrace accessions were screened for resistance to two highly virulent races of anthracnose (race 2047 and race 3481) and for resistance to the BCMNV strain NL‐3. Thirteen accessions, all wild, were resistant to both anthracnose races, with MX‐QT‐3 and PI 661812 displaying complete resistance with no disease symptoms across all replications. Surprisingly, no natural resistance to BCMNV strain NL‐3 was detected in the wild germplasm. PI 442541, PI 661891, and W6 10164 were the only three accessions that expressed the I‐gene phenotype and all three have some history of cultivation. This study provides a resource for introgression of genetic diversity for anthracnose resistance into cultivated beans and reveals that innate resistance to BCMNV may not exist in wild populations of P. vulgaris. Core Ideas: Wild Phaseolus vulgaris germplasm has genetic and phenotypic diversity not present in cultivated varieties.Resistance to two races of anthracnose exists in wild bean germplasm.Resistance to BCMNV NL‐3 was not found in wild bean germplasm, but in three landraces. [ABSTRACT FROM AUTHOR]

Colletotrichum gloeosporioides is the main pathogen that causes poplar anthracnose. This hemibiotrophic fungus, which can severely decrease the economic benefits and ecological functions of poplar trees, infects the host by forming an appressorium. Hox7 is an important regulatory factor that functions downstream of the Pmk1 MAPK signaling pathway. In this study, we investigated the effect of deleting CgHox7 on C. gloeosporioides. The conidia of the ΔCgHox7 deletion mutant germinated on a GelBond membrane to form non-melanized hyphal structures, but were unable to form appressoria. The deletion of CgHox7 weakened the ability of hyphae to penetrate a cellophane membrane and resulted in decreased virulence on poplar leaves. Furthermore, deleting CgHox7 affected the oxidative stress response. In the initial stage of appressorium formation, the accumulation of reactive oxygen species differed between the ΔCgHox7 deletion mutant and the wild-type control. Moreover, CgHox7 expression was necessary for maintaining cell wall integrity. Considered together, these results indicate that CgHox7 is a transcription factor with crucial regulatory effects on appressorium formation and the pathogenicity of C. gloeosporioides. [ABSTRACT FROM AUTHOR]

Anthracnose, caused by species in the Colletotrichum orbiculare complex, is a major foliar disease in open‐field cucumber farming worldwide. This study aimed to develop and validate a standard area diagram (SAD) set to estimate the severity of anthracnose on cucumber leaves. For this purpose, a SAD set with nine levels of severity (1; 3; 5; 10; 20; 30; 40; 50 and 60%) is proposed. The SAD set was validated by 16 raters with no experience in evaluating plant diseases. Both accuracy and precision improved when the proposed SAD set was employed. The statistical parameters were bias coefficient factor‐Cb (no SAD set = 0.891, with SAD set = 0.982); correlation coefficient‐r (no SAD set = 0.851, with SAD set = 0.941); and Lin's concordance correlation coefficient‐ρc (no SAD set = 0.755, with SAD set = 0.924). In addition, estimates were more reliable: intra‐class correlation coefficient‐ρ (no SAD set = 0.646, with SAD set = 0.887). The SAD set proposed here is a useful tool for improving visual assessments of anthracnose severity on cucumber leaves. [ABSTRACT FROM AUTHOR]

The species composition of the strawberry anthracnose pathogen population in Saga Prefecture was investigated through phylogenetic analysis of the nucleotide sequences of the intergenic regions of the apn2 and MAT1-2–1 genes. Here, 77 out of the 80 Colletotrichum isolates used were classified as C. fructicola, and the remaining three were classified as C. siamense. The 77 C. fructicola isolates were tested for sensitivity to fludioxonil, which is widely used as the main fungicide in rotational programs in Saga Prefecture. High levels of resistance to fludioxonil were observed in 14 C. fructicola isolates tested for sensitivity to mycelial growth in fludioxonil-containing media. Furthermore, two inoculation assays using strawberry seedlings treated with fludioxonil were performed on five of the 14 isolates that showed high levels of resistance. The effectiveness of fludioxonil was significantly low in these isolates. To our knowledge, this is the first study to report fludioxonil resistance in a C. fructicola population. [ABSTRACT FROM AUTHOR]

[Objective] The study aimed to identify the species of the pathogen of Kadsura coccinea (Lem.) A. C. Smith, screen out suitable fungicides, and provide theoretical basis for the identification and field prevention of the pathogen of K. coccinea. [Method] The pathogen of K. coccinea leaves collected from Yunfu, Guangdong province were isolated by tissue block separation method, which was determined based on Koch's postulates and was identified by morphology and molecular biology. The mycelial growth rate method was used for biological testing, as well as indoor toxicity of different fungicides to K. coccinea. [Result] By isolating and purifying the diseased leaves, a total of 6 strains were obtained. And representative strain Al was selected for morphological identification and ITS sequence analysis. The pathogen of K. coccinea was identified as Colletotrichum sp.. Through biological testing of strain Al, it was determined that the most suitable growth medium was PDA medium, the most suitable temperature for mycelial growth was 28 °C, the lethal temperature was 53 °C for 10 minutes, the optimal pH for mycelium growth was 6.0, the optimal lighting conditions were continuous darkness, the optimal carbon and nitrogen sources for this mycelium were maltose and yeast powder. Among the four tested fungicides of thiram, bromoxynil, carbendazim and azoxystrobin, carbendazim had the best inhibitory effect, with an EC50 value of 0. 14 µg/mL.. Followed by thiram and bromoxynil, with EC50 values of 55. 26 and 55.32 µg/ml., respectively, indicating that they had better inhibitory that effect. The EC50 value of azoxystrobin was 791.95 µg/mL, with a range of 100-1000 µg/mL., and the antibacterial effect was not significant. [Conclusion] The results show that Colletotrichum sp. is the pathogen of Kadsura coccinea collected from Yunfu, Guangdong province. Carbendazim, thiram and bromoxynil could be used as candidate field control agents for the pathogen of K. coccinea. [ABSTRACT FROM AUTHOR]

Introduction: Anthracnose is a significant fungal disease that affects tree growth and development, with Colletotrichum spp. exhibiting host non-specificity and targeting various organs, making disease control challenging. Methods: This study aimed to identify the pathogenic species causing anthracnose in Ilex macrocarpa in Nanchong, Sichuan Province, and screen effective fungicides, particularly biological ones. The pathogen was identified as Colletotrichum fioriniae through morphological observation, pathogenicity assays, and molecular biological methods. Three biological and five chemical fungicides were evaluated for their effects on the mycelial growth and spore germination rate of the pathogen. Results: The results indicated that prochloraz was the most effective chemical fungicide, while the cell-free supernatant (CFS) of Bacillus velezensis had the most significant inhibitory effect among the biological fungicides. Transcriptome analysis revealed that the CFS of B. velezensis significantly reduced the expression of genes associated with ribosomes, genetic information processing, membrane lipid metabolism, and sphingolipid biosynthesis in C. fioriniae. Additionally, the glutathione pathway's expression of various genes, including key genes such as GST, GFA, Grx, TRR, and POD, was induced. Furthermore, the expression of 17 MFS transporters and 9 ABC transporters was increased. Autophagy-related ATGs were also affected by the B. velezensis CFS. Discussion: These findings suggest that the B. velezensis CFS may inhibit C. fioriniae through interference with ribosomes, genetic information processing, cell membrane metabolism, and energy metabolism. These results provide potential target genes for the B. velezensis CFS and insights into the antifungal mechanism by which B. velezensis inhibits C. fioriniae. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose caused by Colletotrichum spp. has resulted in significant losses in strawberry production worldwide. Strawberry anthracnose occurs mainly at the seedling and early planting stages, and Colletotrichum siamense is the main pathogen in North China, where mycelia, anamorphic nuclei, and conidia produced in the soil are the main sources of infection. The detection of pathogens in soil is crucial for predicting the prevalence of anthracnose. In this study, a visualized loop-mediated isothermal amplification (LAMP) assay and a loop-mediated isothermal amplification method combined with a TaqMan probe (LAMP-TaqMan) assay were developed for the β-tubulin sequence of C. siamense. Both methods can detect Colletotrichum siamense genomic DNA at very low concentrations (104 copies/g) in soil, while both the visualized LAMP and LAMP-TaqMan assays exhibited a detection limit of 50 copies/μL, surpassing the sensitivity of conventional PCR and qPCR techniques, and both methods showed high specificity for C. siamense. The two methods were compared: LAMP-TaqMan exhibited enhanced specificity due to the incorporation of fluorescent molecular beacons, while visualized LAMP solely necessitated uncomplicated incubation at a constant temperature, with the results determined by the color change; therefore, the requirements for the instrument are relatively straightforward and user-friendly. In conclusion, both assays will help monitor populations of C. siamense in China and control strawberry anthracnose in the field. [ABSTRACT FROM AUTHOR]

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Sorghum northern anthracnose is a leaf disease affecting sorghum, which results in plant death and substantial yield loss. This study aimed to effectively understand the disease, clarify its biological characteristics, and evaluate the resistance of germplasm resources. A field sample was collected to isolate and purify the pathogen. The pathogen, identified as Kabatiella zeae Narita et Hiratsuka using both morphological and molecular techniques, was further confirmed as the causative agent of northern anthracnose of sorghum following Robert Koch's principles. The results revealed the optimal culture temperature to be 25 °C, preferred dark culture conditions, and the best growth on potato glucose agar medium with sucrose and L-leucine as the optimal carbon and nitrogen sources, respectively. A total of 138 sorghum germplasm resources were inoculated and evaluated using the isolated pathogen, with 20 lines (14.49%) exhibiting high resistance, 18 lines (13.04%) showing disease resistance, 27 lines (19.57%) demonstrating medium resistance, 37 lines (26.81%) being susceptible, and 36 lines (26.09%) classified as highly susceptible. The indoor fungicide screening was conducted through pathogen medium application, and enilconazole, pyraclostrobin, methylthiophanate, and flusilazole were screened for the best fungicide inhibition with a 100% inhibition rate compared with the control. This study provides reference for field pharmaceutical control in sorghum production. [ABSTRACT FROM AUTHOR]