Anthracnose Disease Research Articles

Complete genome analysis and antimicrobial mechanism of Bacillus velezensis GX0002980 reveals its biocontrol potential against mango anthracnose disease.

Post-harvest anthracnose significantly affects the yield and quality of mangoes. In this study, an antagonist bacterium, GX0002980, with strong inhibitory effect against Colletotrichum gloesporioides, the pathogen of mango anthracnose, was isolated from the rhizosphere soil of plants. Based on morphological characteristics, physiological and biochemical tests, and 16S rRNA gene and gyrB gene sequencing analysis, the strain was identified as Bacillus velezensis. Strain GX0002980 exhibits broad-spectrum antibacterial capabilities, and its volatile substances and sterile fermentation filtrate also demonstrate antagonistic effects against C. gloesporioides. This strain can produce antimicrobial substances that inhibit pathogen growth, such as amylase, cellulase, protease, pectinase, and siderophores, and has plant-growth-promoting characteristics, such as nitrogen fixation, NH3 production, and phosphate solubilization. Whole-genome sequencing results show that the genome size of GX0002980 is 3,907,381 bp with a guanine and cytosine content of 47.44%. The antiSMASH analysis predicts 14 antimicrobial biosynthesis gene clusters within the GX0002980 genome, including surfactin, fengycin, bacilysin, macrolactin H, bacillaene, difficidin, and bacillibactin. Liquid chromatography-mass spectrometry analysis revealed that the antimicrobial active substances secreted by GX0002980 include surfactin, bacilysin, butirosin A, and more. Strain GX0002980 has an in vitro control efficiency of 52% against mango anthracnose, and it can effectively suppress the occurrence of post-harvest diseases in mangoes, extending their storage time. In conclusion, B. velezensis GX0002980 possesses multiple biocontrol mechanisms and has potential for application in the biological control of mango anthracnose.IMPORTANCEBacillus velezensis GX0002980 showed biocontrol potential against Colletotrichum gloesporioides, a causative agent of mango anthracnose. B. velezensis GX0002980 produces a variety of secondary metabolites with antibacterial properties. Whole-genome sequencing revealed potential active metabolite synthesis gene clusters of B. velezensis GX0002980. B. velezensis GX0002980 has a significant effect on the control of post-harvest disease in mango fruits.

Lupins: A Remarkable Protein Crop Battling Anthracnose for a Greener Future

Abstract Lupins ( Lupinus spp.) are protein-rich legumes, serving as a sustainable alternative to soybeans and valued for both human and animal nutrition. Besides their high-yield potential, lupins enhance soil fertility and provide habitat for wild pollinators, boosting agrobiodiversity. However, lupin cultivation faces challenges from anthracnose disease, caused by the fungal pathogen Colletotrichum lupini . This presumed asexual pathogen consists of at least four clonal lineages, all originating from the Andes in South America. Lineage II has spread globally and drives the current anthracnose outbreak. Despite genetic uniformity, variations in morphology and virulence exist among and within lineages, likely due to a diverse transposable element (TE) landscape, mini-chromosome presence, and distinct effector repertoires. Infected seeds are the primary inoculum source and the main vehicle for global spread. Secondary inoculum in the form of conidia produced by necrotic lesions, becomes prevalent at flowering, causing rapid crop devastation. Resistance breeding has proven to be the most effective control strategy, with recently developed resistant varieties now available for the most widely cultivated lupin species. Combining resistance breeding with enhanced disease management and agronomic practices can support the expansion of lupins as a resilient protein crop, strengthening their role in sustainable agriculture. Information © The Authors 2025

First Report of Colletotrichum nymphaeae Causing Pear Anthracnose in China.

China is a major producer of pears in the world and anthracnose is the most important disease, which may include fruit rot and early defoliation, and further brings enormous economic losses. In August of 2023, a sudden outbreak of anthracnose disease, ranging from 70% to 90% disease incidence, occurred on fruits of Pyrus pyrifolia (Burm.f.) Nakai in 200 acres of three pear orchards at Baiyi town, Guiyang city, Guizhou Province of China. Thirty diseased fruits were randomly collected three pear orchards, i.e., 10 fruits from each, and transported to the laboratory for analysis. The symptoms showed dark brown lesions that extended rapidly causing sunken fruit rot lesions harboring orange conidial clumps. To identify the pathogen, three from the 10 diseased fruits per orchard were used for isolation. Small tissue pieces of diseased fruits were disinfected and rinsed twice with 75% alcohol and sterile water, placed on a potato dextrose agar (PDA), and cultured at 25℃ in a dark (Fang, 1998). Ten isolates with same colony morphology were obtained. Two isolates, GZ-3 and GZ-5, were randomly selected for further analysis. The GZ-3 and GZ-5 isolates grew on PDA plates at an average daily growth rate of 0.8~1.0 cm/d in the darkness at 25℃. The colonies were white to gray on the front side and greyish-green to orange on the reverse side. The conidia were hyaline, smooth, nonseptate, and fusiform, measuring 9.0-19.2×2.5-6.1 μm, with the average mean of 13.9±2.2×4.4±0.9 μm (n=50) for GZ-3, and the size of 9.5-15.4×2.3-4.8 μm, with average size of 13.1±1.5×3.7±0.5 μm (n=50) for GZ-5, respectively. The morphological characteristics of the GZ-3 and GZ-5 colonies were consistent with those of Colletotrichum acutatum complex (Damm et al. 2012). To confirm the pathogenicity, the 6 × 106 mL-1 spore suspension of GZ-3 and GZ-5 were inoculated on healthy P. pyrifolia (Burm.f.) Nakai fruits using the non-invasive spray method, while sterile water was used to inoculate control fruits. The fruits inoculated with the two isolates exhibited dark brown spots in the early stage of the disease, then the lesions expanded to rot and produced orange conidia. GZ-3 and GZ-5 were reisolated from the fruits, fulfilling Koch's postulates. The internal transcribed spacer (ITS) rDNA, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), actin (ACT), chitin synthase 1 (CHS-1) and β-tubulin (TUB2) were partially amplified using the primers designed previously (Weir et al. 2012) and sequenced. The above five gene sequences from GZ-3 showed 99.63% to 100% identity with those of GZ-5, respectively. The GZ-3 sequences were deposited in GenBank (ACT: PP825836; TUB2: PP825837; CHS-1: PP825838; GAPDH: PP825839; ITS: PP821112). The sequence alignment was performed based on the concatenated sequence of ACT-TUB2-CHS-1-GAPDH-ITS. A phylogenetic tree, constructed using the Neighbor-Joining method with bootstrap replication 2200 bootstrap alignments in MEGA11.0, showed GZ-3 and GZ-5 clustering with reference C. nymphaeae isolates. Based on the obtained morphological characterization and phylogenetic analysis results, GZ-3 and GZ-5 were identified as C. nymphaeae. Currently, 12 Colletotrichum species causing pear anthracnose have been reported in China (Fu et al. 2019). To our knowledge, this is the first report of C. nymphaeae causing pear anthracnose in the country. The findings are significant for a quick monitoring and control of pear anthracnose.

Ficus altissima, a new host of Colletotrichum fructicola Causing anthracnose in China.

Ficus altissima Blume.，known as council treeor lofty fig, is a tall evergreen tree in the Moraceae family, widely planted as a roadside tree due to its exquisite tree posture in subtropical areas. During October 2023, an anthracnose disease was observed in approximately 90% of F. altissima plants in Mazhang, Zhanjiang, Guangdong Province ( 22°6'14.7''N,110°27'26.8''E ). Symptoms were small dark-brown or black spots with yellow halos on about 10% disease leaves, which downgraded its ornamental value (Figure 1). Twenty-four diseased tissues (5 × 5 mm) were cut and sterilized with 3% hydrogen peroxide for 2 min, rinsed three times with sterile water, and placed on potato dextrose agar (PDA) medium containing 50 mg/L of penicillin. The plates were incubated in the dark at 28°C. Nineteen isolates were obtained by the single-spore method (Choi et al. 1999). The colonies on PDA were cotton-like, gray-black with concentric ring on the mycelial mat, and orange conidiomata appeared after seven days (Figure 1). The conidia are unicellular, oblong in shape and 11.9-16.1 μm × 6.1-10.9 μm (av. 13.9 × 7.3 μm, n = 50) in size. Appressoria were irregularly, dark brown, some with lobes, elliptical, 10.9-12.4 × 6.4-9.5µm (av. 11.7 × 8.2 μm) (Figure 1). The morphological characteristics were consistent with those of Colletotrichum species (Weir et al. 2012). The internal transcribed spacer (ITS) region, actin (ACT), chitin synthase (CHS), glyceraldehydes-3-phosphate dehydrogenase (GAPDH), and B-tubulin (TUB) were amplified and sequenced for two isolates (R3-2 and R3-4) with primer pairs of ITS1/ITS4 (White et al. 1990), ACT-512F/ACT-783R, CHS-79F/345R, GAPDH-F/R, and TUB-2Fd/4Rd, respectively (Weir et al. 2012). The sequences were deposited in GenBank (ITS: PQ013063 and PQ432515, TUB: PQ066260 and PQ433584, ACT: PQ066256 and PQ433581, GAPDH: PQ066259 and PQ433583, CHS: PQ066258 and PQ433582). BLAST research showed the sequences of R3-2 and R3-4 had above 99% identity with these of C. fructicola ex-type ICMP: 18581 (ITS: 481/481 (100%) and 481/482 (99%); GAPDH: 277/280 (99%) and 278/281 (99%); TUB: 406/406 (100%) and 379/379 (100%); CHS: 267/267 (100%) and 299/299 (100%); ACT: 239/241 (99%) and 269/270 (99%)). The concatenated data of ITS, TUB, CHS, ACT and GAPDH sequences was used to phylogenetic analysis using Maximum Likelihood method in MEGA-X. The isolates R3-2 and R3-4 clustered in the same clade with C. fructicola ICMP 18581 (Figure 2). To confirm pathogenicity, three healthy leaves of 8 to 10-year-old F. altissima were surface sterilized with 75% ethanol and sterile water, wounded on each leaf with sterile needles. The wounded sites were inoculated with 10 µl of spore suspension (1×105 spore/ml) and inoculated with sterile water as control. The experiment was repeated three times. After three days, symptoms of anthracnose were observed on the leaves, similar to those described above; no symptoms occurred in the controls. Colletotrichum fructicola was re-isolated from artificially inoculated leaves, all re-isolated fungal isolates similar to R3-2 and R3-4 morphology and re-confirmed by molecular analysis. In China, C. fructicola may infect 20 species of plants from 11 genera (Farr and Rossman 2024) and it is the first report causing F. altissima anthracnose, which provided a basic knowledge for diagnosing, preventing and controlling this disease.

Comparative genomic analysis reveals the difference of NLR immune receptors between anthracnose-resistant and susceptible sorghum cultivars

Anthracnose, caused by Colletotrichum sublineola, is a prevalent disease that noticeably affects global sorghum production. Nucleotide-binding leucine-rich repeat receptors (NLRs) are crucial for disease resistance. Here, we report the differences in the number, expression profile, and gene structure of NLRs between the anthracnose-resistant and susceptible sorghum cultivars. Through a systematic anthracnose disease assay on 365 sorghum accessions, we identified the American improved cultivar BTx623 as the resistant and the Chinese improved glutinous cultivar Guojiaohong1 (GJH1) as the susceptible cultivar. Then we sequenced the genome of GJH1 and identified 239 NLRs, substantially fewer than the 302 in BTx623. Although the collinear NLRs are highly conserved between GJH1 and BTx623, more than half of the non-collinear NLRs showed notable mutations or structural variations. During C. sublineola infection, BTx623 exhibited a higher number of highly expressed and inducible NLR genes than GJH1 did. Moreover, we identified some candidate anthracnose resistance genes that are potentially valuable for disease-resistant breeding. Therefore, our data provide genetic resources for developing disease-resistant glutinous sorghum.

Identification and Pathogenicity of Fungi Associated with Anthracnose Disease of Pepper (Capsicum annuum L.) In Lafia, Nasarawa State

Anthracnose disease is a critical challenge in pepper cultivation, particularly in tropical and subtropical regions like Nigeria, leading to significant yield losses and reduced fruit quality annually. A study was conducted to identify and control pathogens associated with anthracnose disease of pepper fruits in Lafia. Fungi associated with infected fruits were isolated and identified using morphological characteristics. Identified fungi were subjected to pathogenicity tests to evaluate their disease producing potentials in healthy pepper fruits. Results of morphological identification of the fungi isolated from anthracnosed pepper fruits in Lafia showed that the fungi were identified in two genera, namely Aspergillus and Fusarium. Results of pathogenicity test showed that fruit rot diameters were higher in fruits inoculated with A. niger (5.12 cm), compared to fruits inoculated with Fusarium sp. (1.90 cm diameter) after six days. The differences in rot diameters among the pepper fruits inoculated with the two fungi were significant (P ≤ 0.05). Control measures targeted at the prevention of fruit contamination by A. niger will go a long way to minimize yield losses of tomato in the study area.

Elucidating the mechanism of resistance to anthracnose in litchi leaves through transcriptome analysis

BackgroundLitchi, an important tropical fruit, is severely affected by anthracnose disease. However, the mechanism of its disease resistance response remains unknown, and resistant accession genetic resources and resistance-related genes have not yet been identified.ResultsIn this study, 82 accessions of litchi were evaluated for resistance to Colletotrichum gloeosporioides, and the accessions ‘Haiken 5’ and ‘Nongmei 5 hao’ were identified as resistant and susceptible, respectively. Leaves from these two accessions were inoculated with C. gloeosporioides and collected at 6 and 24 h for use as materials for transcriptome analysis. Analyses of the differentially expressed genes (DEGs) between the accessions and their controls, which were inoculated with potato dextrose agar medium, revealed that the resistant accession presented more DEGs with smaller changes in magnitude, whereas the susceptible accession presented fewer DEGs with greater changes in magnitude. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed, and phenylpropanoid biosynthesis, amino sugar and nucleotide sugar metabolism, and plant–pathogen interactions were identified as common pathways. Chitinase activity, oxidoreductase activity, aminoglycan and glucosamine-containing compounds, and cell wall metabolic processes also participated in the defence reaction. Salicylic acid signalling in litchi leaves contributed to resistance to C. gloeosporioides. Short Time-series Expression Miner (STEM) and weighted correlation network analysis (WGCNA) were also employed to evaluate the gene expression trends and identify highly correlated genes.ConclusionLitchi accessions presented different resistance responses to anthracnose disease. Small changes in the expression levels of critical resistance-related genes were sufficient to produce the defence reaction. Calcium ion regulatory mechanisms and transcription factors have been preliminarily identified as contributors to disease resistance. Multiple pathways and molecular processes participate in the defence response. These results identify candidate genes and pathways involved in litchi plant defence against anthracnose.

First Report of Anthracnoseon on Annona squamosa L. Caused by Colletotrichum fructicola in China.

Annona squamosa L. is a tropical fruit, cultivated in various provinces of China, such as Guangxi, Taiwan, and Yunnan. This fruit has good edible and medicinal value. In November 2021, anthracnose on A. squamosa L. fruits was observed in a plantation in Longzhou (22°11´N, 106°51´E), Guangxi, China. The incidence rate of the plantation was 13.6%. The symptoms included gray-black to black spots, initially small and blackish brown, which expanded into large irregular spots(Fig.1A-B). To isolate the pathogen, symptomatic fruits were collected and small pieces (5 mm2) were cut from the lesions, surface sterilized in 75% ethanol for 15 seconds, followed by 2% AI sodium hypochlorite solution for 3 minutes, rinsed three times with sterile water, and incubated on PDA at 28°C. A total of 23 isolates with identical morphology were obtained and 3 representative isolates (FLZ-1 to FLZ-3) were selected for further characterization. The fungal colonies presented concentric rings on PDA plates, initially white, later turning gray green and producing light orange conidia(Fig.1C). The mature conidia were cylindrical, unicellular, with dimensions of 11.09-20.02 μm × 4.06-6.54 μm, usually containing 2 oil droplets with a size of 3.21-8.36 μm × 2.50-4.55 μm, and L/W ratio of 1.11-2.09(n=100) (Fig.1D). These morphological features were aligned with those of Colletotrichum spp. (Weir et al. 2012). To confirm the identity of the isolates, DNA was extracted and specific gene regions were amplified and sequenced using the following primer sets: ITS (ITS1 and ITS4), GAPDH (GPD1 and GPD2), ACT (ACT-512F and ACT-783R), TUB (T1 and Bt2b), CHS-1 (CHS-79F and CHS-354R), and ApMat (AM-F and AM-R) (Wang et al. 2024). Sequences were submitted to GenBank (Accession nos. PP968176 to PP968178 for ITS, PQ122814 to PQ122816 for GAPDH, PQ122808 to PQ122810 for ACT, PQ169643 to PQ169645 for TUB2, PQ122811 to PQ122813 for CHS-1, and PQ152017 to PQ152019 for ApMat). Maximum likelihood phylogenetic analysis using combined sequences of ITS, GAPDH, ACT, TUB2, CHS-1 and ApMat in MEGA X confirmed the isolates as Colletotrichum fructicola (Fig.2), marking the first report of this pathogen on A. squamosa L. in China. Pathogenicity tests were conducted on wound and nonwound healthy A. squamosa L. fruits to confirm the pathogenicity of the isolated C. fructicola. The fruits were wounded using a sterile needle. Each wounded and nonwounded fruit was inoculated with a 10 µL conidial suspension (1×106 conidia/mL) drop at corresponding sites. Control fruits were inoculated with sterile water. Five fruits per treatment were used and the experiment repeated three times. The fruits were placed in an incubator at 28°C and 85% RH. Anthracnose symptoms developed on the inoculated fruits within 5 days (Fig.1E-F), while control fruits remained symptom-free (Fig.1G-H). C. fructicola was successfully reisolated from the symptomatic fruits, fulfilling Koch's postulates and confirming its role as the causal agent of the disease. According to previous reports, C. fructicola also causes anthracnose on Psidium guajava (William R. O et al. 2024), leaf spots on apple (Moreira Rafaele R et al. 2019), and Kadsura coccinea (Jiang et al.2021). This study identifies C. fructicola as the pathogen causing anthracnose on A. squamosa L. and no cases have yet been discovered in the field in China. This report will raise awareness among growers about the anthracnose disease of A. squamosa L. and develop effective disease control strategies.

Bored Rotten: Interactions Between the Coffee Berry Borer and Coffee Fruit Rot

The coffee berry borer (CBB) is the most destructive pest of coffee worldwide, with damages exceeding $500 M a year and affecting the livelihood of 25 million farmers. Coffee fruit rot (CFR) is described as an anthracnose disease; it can cause up to 80% loss of the crop on susceptible cultivars when conditions favor it. These two serious threats to coffee production have been studied separately, but a link between them was not shown until recently. Several recent studies show that CBB damage is associated with a higher incidence of fruit rot; CBBs carry Colletotrichum and Fusarium fungi, also found in rotted fruits, and can transmit disease to coffee fruits as they bore into them. Previous studies on the relationship between CBB and Fusarium did not take into account that Fusarium is involved in coffee fruit rot, so these recent findings shed new light on the relationship. Here we discuss this relationship and its implications, both ecological and practical.

First Report and Molecular Characterization of <i>Colletotrichum gloeosporioides</i> Associated with Anthracnose of Olive Fruit in the Pothwar Plateau of Pakistan

This study reports the first identification of Colletotrichum gloeosporioides as the causal agent of anthracnose disease on olive fruit in Pakistan. During disease surveillance in olive orchards of Pothwar Plateau (32 ° 33 ′ and 34 ° 3 ′ N, and 71 ° 89 ′ and 73 ° 37 ′ E), anthracnose symptoms were observed in multiple farmer fields with disease incidence up to 85% and prevalence of 93%. Morphological identification, followed by molecular confirmation through ITS sequencing, identified Colletotrichum gloeosporioides as the pathogen responsible for fruit rot/anthracnose. Pathogenicity tests confirmed its ability to infect healthy olive fruits, causing typical anthracnose symptoms. This is the first documented occurrence of C. gloeosporioides on olive in Pakistan, contributing significant insights into the fungal pathogens impacting olive cultivation in the region.

First report of Colletotrichum fructicola causing Anthracnose on the leaf of flowering cherry (Prunus serrulata 'Sekiyama') in China.

Flowering cherry (Prunus serrulata) is a notable garden tree that blooms in early spring. In June 2023, an anthracnose disease was identified on 60% of P. serrulata 'Sekiyama' plants in the Fenghuanggou Scenic Area (0.2 ha.) in Nanchang City, Jiangxi Province (28.37° N, 116.01° E). At early disease stages, brown, small spots (0.5 to 1 mm) appeared on the upper surface of leaves. Subsequently, a chlorotic halo developed around each lesion. Then necrotic lesions were enlarged, the leaves were perforated. Ten symptomatic leaves were collected from 5 trees, rinsed under running water for 3 min, sectioned into 5×5 mm pieces, disinfected in 75% ethanol for 30 sec and rinsed three times with sterile water. Tissue pieces were placed on potato dextrose agar (PDA) and incubated at 27 °C for three days. Among the 15 isolates, 5 isolates with similar morphology were obtained from the 10 infected tissue pieces. Colonies were off-white with cotton-like hyphae, with the reverse of the culture became brownish. Conidia were hyaline, smooth-walled, cylindrical, aseptate, and had wide rounded ends and were measured 0.91 to 1.41 μm × 2.11 to 3.18 μm (n=28). To identify these isolates, ITS1/ITS4 (Gardes and Bruns, 1993) primers were first used to amplify the ITS sequence, and it was found that the five isolates had 100% homology to the genus Colletotrichum (Tang et al., 2022). One isolate (ZJ1-1) was selected for subsequent verification, and partial chitin synthase (CHS), calmodulin (CAL) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified with the primers CHS-79F/CHS-345R (Carbone and Kohn, 1999), CL1C/CL2C (Weir et al., 2012) and GDF/GDR (Templeton et al., 1992), respectively. Sequences were deposited in GenBank as accession numbers PP481926 (CHS), PP481927 (CAL), PP481925 (GAPDH), and PP077091 (ITS). Blast analysis demonstrated that the sequences were 99% to 100% identical with those of Colletotrichum fructicola isolate ICMP18646 (JX009874, JX009674, JX010032, JX010173). A phylogenetic tree was produced using CHS-CAL-GAPDH-ITS concatenated sequences in MEGA 11.0 and found that ZJ1-1 was assigned to the C. fructicola clade with 95% bootstrap support. According to its morphological characteristics and molecular biology, the strain was identified as C. fructicola ( Kang et al., 2023). The fungus ZJ1-1 was inoculated onto healthy 3-year-old P. serrulata 'Sekiyama' trees. 3 trees were wounded and inoculated with 10 μL spore suspension (1.0×106 conidia/mL) of ZJ1-1, and other 3 trees were inoculated with sterile ddH2O to act as the control. The inoculated plants were incubated in a greenhouse with 27 ℃ and 95% RH. Each plant was inoculated on three leaves, with three replicates. Symptoms of anthracnose appeared on the third day following inoculation, but no symptoms appeared on the trees maintained as controls. C. fructicola was re-isolated (named 003) from the inoculated leaves and confirmed by the methods described above, whereas no fungus was isolated from the control plants. To our knowledge, C. fructicola caused anthracnose has been reported on Paeonia lactiflora, Prunus avium and Prunus sibirica (Kang et al., 2023; Zhou et al., 2023; Han et al., 2023), but this is the first report of C. fructicola causing leaf spot disease on flowering cherry in China. C. fructicola can induce leaf defoliation of flowering cherry in severe cases, and further investigations are required to ascertain the potential pathogenicity of other Colletotrichum sp.

Temporal and Spatial Dynamics of Anthracnose (Colletotrichum sublineolum) Disease on Selected Sorghum Genotypes at Assosa Zone, Western Ethiopia

Background Over 500 million people worldwide rely on sorghum as a main food crop. About 10% of the daily caloric intake of households in Ethiopia’s northwest and eastern regions, including Benishangul Gumuz, comes from sorghum. A hemi-biotrophic fungal pathogen called Colletotrichum sublineolum caused anthracnose disease is among the biotic constraints of sorghum production. Methods Ten selected sorghum genotypes were assessed for sorghum anthracnose severity and its temporal and spatial dynamics on field plots in the districts of Assosa and Bambasi. The performance of the chosen sorghum genotypes was assessed using the following metrics: AUDPC, disease progress rate, yield-related trait, sorghum grain yield, and mean severity index. Anthracnose severity was evaluated using a 1–5 disease rating scale and assessments conducted at seven consecutive time points. Results The result found that the mean anthracnose severity index ranging from 60-77 PSI and 53-82 PSI, respectively. AUDPC varied from 351 to 470 % days and 316 to 499 % days at Assosa and Bambasi districts, respectively. Bambasi district achieved a larger grain yield than the Assosa district. Assosa-1 demonstrated a significant level of disease pressure, yet the current investigation found that this genotype is the highest performing genotype in both locations. Conclusions There is a considerable positive link between the severity of anthracnose and the weekly total rainfall and relative humidity. At both trial sites, Mersa-1 continuously produced higher grain yields and reduced disease levels. Breeders might utilize the Baco Striga sorghum genotype as a check line in a breeding effort to resist anthracnose disease because it shown a high vulnerability to the disease at both locations.

Effects of conventional and ridge planting methods at different plant densities on yield and yield components in chickpea

Objective: This study was carried out to determine the applicability of the ridge sowing method and the appropriate sowing density for chickpeas on existing ridges after cotton under rain-dependent conditions. Material and Methods: The trials were carried out at split randomized block design with three replications. Two planting methods (ridge planting and conventional planting), and five planting density (30, 35, 40, 45 and 50 seed per square meter) were discussed as application issues. Results: It was determined that ridge planting method was better than conventional planting method in terms of investigated characters as days to 50% flowering, days to maturity, plant height, first pod height, primary branches plant-1 and anthracnose disease value in the study. It was seen that seed yields were affected less from environmental climate changes for ridge planting method, and anthracnose disease value occurred at lower ratio compared to conventional planting. It was determined that the convenient planting density of chickpea was 40 seed per square meter for conventional planting and 45 seed for ridge planting in the economic analysis. Conclusion: The average yield of the conventional planting method after cotton using the appropriate planting density (2081.7 kg ha-1) was found to be 6.2% higher than the yield of the ridge planting method (1960.0 kg ha-1). However, in the economic analysis, it was determined that ridge planting was 9.2% more profitable than the conventional planting method in terms of net income.

Morpho-molecular identification of Colletotrichum scovillei causing anthracnose disease of banana in Pakistan.

Banana (Musa spp.) is widely cultivated as the major fruit in Pakistan. Anthracnose fruit rot caused by various Colletotrichum spp. is a serious disease. Sample of 23 banana fruits were obtained from 4 commercial orchards (43% incidence) in Uthal, Balochistan, Pakistan. One or more small light-brown to reddish-brown spots were observed on all fruits during early stage of infection and later became sunken lesion. The pieces of diseased tissues were cut from margins, surface sterilized with sodium hypochlorite (0.3%), rinsed in sterile distilled water, dried on sterile filter papers and shifted on potato dextrose agar (PDA). Colony morphology of all isolates (n=21) on PDA were white fungal colonies which became dark gray after 7 days. Smooth, aseptate, cylindrical and hyaline conidia (n=20 per isolate) were recorded and measured 10.2 to 16.1 (avg. 12.3) × 3.7 to 4.5 (avg. 3.8) µm. Genomic DNA was extracted from a representative isolate LUAWMS and sequences from the internal transcribed spacer region (ITS), β-tubulin (TUB2), calmodulin (CAL), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), actin (ACT) and chitin synthase 1 (CHS-1) genes were amplified through polymerase chain reaction with the primer pairs ITS1/ITS4, BT1/BT2, CAL1/CAL2, GAPDH1/DAPDH2, ACTN1/ACTN2 and CHS1/CHS2, respectively. The sequences were exhibiting 100% genetic similarity with previously reported isolates SPTD26 (ITS, accession no PQ780054), PHL6, (TUB2, accession no KY475555), HNCS015 (CAL, accession no KX673577), Cer015 (GAPDH, accession no MK473911), QJ2_1 (ACT, accession no OQ613619) and CAUA43 (CHS-1, accession no KP145299) of Colletotrichum scovillei. ITS, TUB2, CAL, GAPDH, ACT and CHS-1 multi-locus sequences were deposited in GenBank under the accession numbers OK493385, OK493386, OK493387, OR449357, OR449358 and OR449359, respectively. For the confirmation of Koch's postulates, banana fruits (n=3) were surface sterilized with 70% ethanol, washed with sterile distilled water and wounded with the help of sterile needle. The spore suspension (1 × 106 conidia/mL) from LUAWMS were pipetted (10 µL) on wound fruit and incubated at 28°C with 12 h dark and light cycle. Moist paper towels was placed on bottom of a sealed crisper box and artificially inoculated fruits were shifted to a humid chamber. Three replicate boxes each contained one banana per treatment. Sterile distilled water was used as a negative control and the experiment was repeated once. After 7 days, small light-brown to reddish-brown spots (length averaged 14.9 mm, std. dev. = 4.0 mm) by 11.3 mm (std. dev. = 1.9 mm) were recorded on artificially inoculated fruits but not on control. Same pathogen was re-isolated from artificially inoculated fruit on PDA and morphological examination and molecular identified was used for the confirmation as previously described. Morphological characterization, molecular identification, multi-locus sequence analysis and Koch postulates confirmed LUAWMS as C. scovillei belongs to C. acutatum species complex (Damm et al., 2012). Previously, C. scovillei was recorded as causal organism of anthracnose disease of banana in China (Zhou et al., 2017), Watermelon in Malaysia (Goh et al., 2022) and pepper in Ontario, Canada (Ellouze, 2024) but to our knowledge, this is the first report of C. scovillei causing anthracnose of banana in Balochistan, Pakistan. The new host-pathogen association could lead to reduced banana yields, higher management costs, and potential trade disruptions due to disease spread and export restrictions.

Foliar symptom-based disease detection in black pepper using convolutional neural network

Black pepper is the most important and widely consumed spice in the world. Insects and diseases are the major concerns for black pepper production, among the many variables causing a decline in black pepper productivity. The major diseases that affect black pepper are foot rot (Phytophthora capsica) and anthracnose (Colletotrichum gloeosporioides). Early and precise diagnosis of diseases is crucial as it will enable the farmers to make timely interventions. In the current scenario, the application of image processing and deep learning techniques for the automatic detection of plant diseases emerges as a solution capable of promptly delivering interventions in time-sensitive scenarios, given its capacity to deliver performance approaching expert levels. Through this study, a deep learning-based approach has been developed to classify black pepper diseases based on leaf images. A model has been developed to detect the two major diseases of black pepper, i.e., anthracnose and foot rot diseases, using a Convolutional Neural Network (CNN) in Kerala, India. We have collected 2786 leaf images from different black pepper farms in Kerala, belonging to three classes of pepper diseases and one healthy leaf class in total. The classes of leaf diseases considered include an early and advanced stage of anthracnose, and Phytophthora foot rot. As the accuracy of the model increases with the number of images, different image augmentation techniques are performed on the originally captured images to generate a total of 18,234 images. The developed CNN model has been compared with eight other pre-trained state-of-the-art models, such as VGG16, VGG19, ResNet50, ResNet50V2, MobileNet V2, DenseNet121, InceptionV3, and Xception. The result shows that the developed CNN model attained a higher classification accuracy, precision, recall, and F1-score of 98.72%, 99.28%, 97.65%, and 98.66% respectively, on the unseen test dataset. A web application named “Black pepper Disease Identification App” for demonstrating the proposed model is developed. According to an overall performance assessment, deep learning is an effective technique for classifying black pepper diseases based on leaf images and identifying them in their early stages. Based on the overall performance, the newly developed model is found to be efficient in classifying the selected pepper diseases. The proposed model holds significant promise for enabling the timely identification of diseases with minimal human intervention. Its deployment benefits both researchers and farmers by facilitating prompt disease detection directly in the field.

Efficacy of Plant Extracts on Management of Anthracnose Disease of Yam (Dioscorea spp.) in Bamenda, Cameroon

Anthracnose is a devastating disease in yam (Dioscorea spp)-growing regions, causing heavy yield losses. This study evaluated the efficacy of plant extracts as alternatives to chemical fungicides used to control yam anthracnose. Yam varieties in five species were used to establish an experiment in a split plot randomized block design at the Research Farm of College of Technology, University of Bamenda from March to September 2023. Scent leaf (Ocimum gratissimum) infusion, neem (Azadirachta indica) seed oil and chemical fungicide (mancozeb) were used to treat yam varieties at 2-weekly interval for four months. Yams were assessed for anthracnose incidence, severity and yield. Fungal isolates from infected plants were identified using morphological traits and pathogenicity tested. Mycelia fragments were inoculated on potato dextrose agar (PDA) media, pre-treated with plants extracts and mancozeb, to test in-vitro mycelia growth inhibition. Incidence of anthracnose was significantly higher (p≤0.05) on untreated plants (40 to 80%) than treated plants (0 to 50%) among yam varieties. Severity of anthracnose was not significantly different (p≤0.05) amongst yam varieties treated with O. gratissimum infusion (25±0.07%, D. rotundata) and mancozeb (20±0.07%, D. rotundata). Tuber yield was lowest among untreated plants (1.8±0.8 kg, D. alata) and highest among plants treated with O. gratissimum infusion (5.3±0.25 kg, D. alata) in all yam species. Fungal isolates were identified as Colletotrichum gloeosporioides and its pathogenicity for anthracnose confirmed. Plant extracts at 100% concentration inhibited mycelia growth (92%, D. dumetorum) with similar (p≤0.05) efficacy to mancozeb (100%, D. dumetorum). This study suggests O. gratissimum infusion and A. indica seed oil as good alternatives of chemical fungicides in integrated management of yam anthracnose, with broader implications in global yam-growing areas.

Efficacy of Bacillus and Trichoderma on growth and anthracnose resistance in scallion

Biotic elicitors, including Trichoderma and Bacillus can improve plant growth and disease resistance. Current research evaluated the efficacy of 14 Bacillus subtilis strains, Trichoderma viride, Trichoderma harzianum, Trichoderma sp. on enhancing growth and managing anthracnose in scallion. The inhibition efficiency of Bacillus and Trichoderma on Colletotrichum growth was assessed in vitro. Besides, effective biotic treatments against anthracnose were evaluated at net house conditions. Then, defence mechanisms including endogenous SA accumulation, production of phenolic compounds, catalase, peroxidase, phenylalanine ammonia-lyase and b-1,3-glucanase were revealed. The results showed that four biotic elicitors, including B. subtilis strains CaSUT008-2, D604, SUNB1 and T. harzianum showed high antagonistic activity against in vitro growth of Colletotrichum colonies at 41-77 %. At 28 days after planting, scallion plants treated with B. subtilis strain CaSUT008-2 and SUNB1 gained stem length at 15.35-15.79 cm. These four biotic treatments had low disease severity in net-house conditions at 25.00-50.00 %. On mechanisms of anthracnose resistance, at 24 hours after inoculation (HAI), scallion plants treated with T. harzianum and B. subtilis strain CaSUT008-2 showed high content of salicylic acid at 2.17-2.20 µg/g fresh weight. At 48 HAI, scallion plants induced by B. subtilis strain SUNB1 increased phenolic compounds at 42.65 µg gallic acid/mg dry mass. Moreover, four biotic elicitors enhanced activities of catalase, peroxidase, phenylalanine ammonia-lyase and b-1,3-glucanase in treated scallion plants. This study suggests that B. subtilis strain CaSUT008-2 and SUNB1, T. harzianum stimulated growth, helped scallion plants against anthracnose disease. The combined Trichoderma-bacteria bio-inoculants may be a good strategy to develop biocontrol agent and plant growth promoter within green and sustainable production of scallion.

Identification of Colletotrichum sp. causing anthracnose disease on chilli pepper in 50 Kota District West Sumatera Indonesia plantation

Abstract Anthracnose fruit rot is an important disease of chilli pepper (Capsicum annuum L) in Indonesia. This study was carried out to identify and characterize the pathogens causing anthracnose disease in chilli peppers (C. annuum L.) grown in 50 Kota district, West Sumatera. Collection of symptomatic fruit was carried out in Luak 50 Kota district, and fungal pathogens were isolated on PDA media in vitro. One isolate chosen in this study is CM1. Morphological characterization, pathogenicity tests and amplification of DNA product with Internal Transcribed spacer region through polymerase chain reaction were demonstrated to identify and confirm that the isolate is the causal of fruit rot anthracnose. The result showed that CM1 isolate is grouped into Colletotrichum sp. isolate based on morphological characterization. Molecular identification and phylogenetic analyses of internal transcribed spacer regions showed that the CM1 isolate has similar nucleotide identity with C. scovillei, with the percentage of homology with the reference isolate is 99.35 %. Pathogenicity testing showed that the isolate was pathogenic to red C. annuum L. both using mycelial plug and conidial suspension. A study on the identification and collection of C. scovillei isolate in Luak 50 Kota will be helpful to increase understanding the distribution of the pathogen in West Sumatera and essential for formulating the effective quarantine policy.

Efficacy of pterostilbene inhibition of postharvest anthracnose on papaya fruit and antifungal mechanisms against Colletotrichum gloeosporioides

Efficacy of pterostilbene inhibition of postharvest anthracnose on papaya fruit and antifungal mechanisms against Colletotrichum gloeosporioides

Exploring mechanisms of resistance to fludioxonil in Colletotrichum fructicola.

Exploring mechanisms of resistance to fludioxonil in Colletotrichum fructicola.