High-quality genome assembly of Pseudopestalotiopsis theae, the pathogenic fungus of tea grey blight

Tea grey blight is one of the most serious foliar diseases of tea tree caused by the plant pathogenic fungus Pseudopestalotiopsis theae which can affect production and quality of tea worldwide. We generated a highly contiguous, 50.41Mbp genome assembly (N50 1.30 Mbp) of P. theae strain CYF27 by combining PacBio long-read and Illumina short-read sequencing technologies. We identified a total of 15,626 gene models, of which 1,038 genes encode putative secreted proteins. The high-quality genome assembly and annotation resource reported here will be useful for the study of fungal infection mechanisms and pathogen-host interaction.

Fungal Endophytes Associated With the Actinorhizal Plant Species, Elaeagnus Latifolia L. (Elaeagnaceae) And Evaluating Their Antagonistic Potential Against Grey Blight Disease In Tea [Camellia Sinensis (L.) O. Kuntze]: A Novel Study From North-East India

The present investigation is a novel approach of exploring the endophytic fungal diversity of Elaeagnus latifolia L., an actinorhizal plant species of North-east India and evaluation of its biocontrol potential against Pestalotiopsis theae, the causal agent of grey blight disease in tea. A total of 17 endophytic fungal species belonging to 12 families and 03 orders were isolated from various parts of E. latifolia L. Isolates were identified based on colony morphology, spore and fruiting bodies using microscopical tools and techniques. Nigrospora sp. showed highest species density (0.5) among all the isolates. Isolation frequency was maximum (67%) in case of Fusarium sp., Nigrospora sp., Penicillium chrysogenum and Rhizopus sp. More fungal isolates were obtained from root and stem (47% each) as compared to leaves (29%). Species richness and diversity indices was maximum (15.0) in stem and minimum (9.0) in leaves. Highest Shannon and Simpson diversity index was in stem (2.02 and 0.860 respectively) followed by root (1.979 and 0.847 respectively) and least in leaves (1.494 and 0.75 respectively). Among the isolates tested for plant growth promoting parameters, EF09 (Fusarium sp.) showed positive response for all the tested parameters. The isolate, EF09 also showed maximum antifungal potential (up to 87.1%) against P. theae in poisoned food technique. Enumeration of endophytic fungal diversity of E. latifolia L. holds promises as the putative strains may lead to the isolation of novel bioactive components for use in industry, medicine and agriculture.

Pestalotioid fungi: A rare agent of onychomycosis among agriculture workers

Background and Purpose: Pestalotioid fungi are ubiquitous environmental molds that have received considerable attention in recent times not only because of their role as a plant pathogen but also owing to their high frequency of retrieval from human diseases. Regarding this, the present study was conducted to investigate onychomycosis caused by pestalotioid fungi, commonly considered important phytopathogens causing grey blight disease in Camellia sinensis. Materials and Methods: A total of 122 agriculture workers were enrolled from Assam, India. Direct microscopic examination was carried out using 40% KOH to determine the presence of any fungal element. Further processing of the specimens for the isolation of fungi was performed using the standard protocol. In addition, the keratinolytic potential of the isolates was evaluated by means of the in vitro hair perforation test. Results: Out of 103 culture-positive samples, non-dermatophyte and dermatophyte molds constituted 82.52% (n=85) and 6.79% (n=7) of the samples, followed by yeasts (n=1, 0.9%) and sterile hyphae (n=10, 9.7%). With regard to the isolated non-dermatophyte molds (82.69%), 4 cases belonged to pestalotioid fungi, such as Neopestalotiopsis piceana (n=1), Pestalotiopsis species (n=1), and Pseudopestalotiopsis theae (n=2). The keratinolytic activity of Pestalotiopsis species showed perforation by disrupting the hair cortex; furthermore, macroconidia were found to be present inside the human hair. Conclusion: A high rate of NDM isolation may be attributed to constant exposure to adverse environmental and occupational hazards. This study highlighted the importance of “pestalotioid fungi” as the rare etiologic agent of onychomycosis. Another remarkable finding was the keratinolytic potential of Pestalotiopsis species, which is unique in this study.

Screening Camelia sinensis Germplasm Against Grey Leaf Blight of Tea

Grey blight is a foliar disease of tea plants (Camellia sinensis) caused by Pestalotiopsis. The grey blight pathogen was isolated from infected leaves of tea plants in the National Tea and High Value Crop Research Institute (NTHRI), Shinkiari, Khyber Pakhtunkhwa, Pakistan. Eight different varieties, Indonesian, Roupi, Jue King, P-5, P-3, Qi man, Chuy and P-1, were investigated for yield loss and resistance against the grey blight disease. All varieties displayed considerably different levels of resistance to Pestalotiopsis (p<0.05). The most resistant variety was Indonesian, which showed the lowest number of lesions (1.5 leaf-1) and the smallest lesion diameter (3.0 cm), whereas the most susceptible variety was P-1 which showed the highest number of lesions (3.83 leaf-1) and the largest lesion diameter (15.0 cm). The grey leaf blight pathogen significantly affected biomass and dry matter of the tested varieties. Compared to non-inoculated control, inoculation with Pestalotiopsis reduced the number of leaves by 40% (p<0.05), fresh leaf weight by 31% (p<0.05) and dry leaf weight by 59% (p<0.05). Whereas, the Indonesian variety was the least affected showing only 11% (p<0.05), 19% (p<0.05), and 28% (p<0.05) reduction in number of leaves, fresh weight and dry weight, respectively, over control. These results showed that Pestalotiopsis significantly reduced tea yield and that this disease can be managed by growing resistant varieties.