Biosynthesis of Fusapyrone Depends on the H3K9 Methyltransferase, FmKmt1, in Fusarium mangiferae

The phytopathogenic fungus Fusarium mangiferae belongs to the Fusarium fujikuroi species complex (FFSC). Members of this group cause a wide spectrum of devastating diseases on diverse agricultural crops. F. mangiferae is the causal agent of the mango malformation disease (MMD) and as such detrimental for agriculture in the southern hemisphere. During plant infection, the fungus produces a plethora of bioactive secondary metabolites (SMs), which most often lead to severe adverse defects on plants health. Changes in chromatin structure achieved by posttranslational modifications (PTM) of histones play a key role in regulation of fungal SM biosynthesis. Posttranslational tri-methylation of histone 3 lysine 9 (H3K9me3) is considered a hallmark of heterochromatin and established by the SET-domain protein Kmt1. Here, we show that FmKmt1 is involved in H3K9me3 in F. mangiferae. Loss of FmKmt1 only slightly though significantly affected fungal hyphal growth and stress response and is required for wild type-like conidiation. While FmKmt1 is largely dispensable for the biosynthesis of most known SMs, removal of FmKMT1 resulted in an almost complete loss of fusapyrone and deoxyfusapyrone, γ-pyrones previously only known from Fusarium semitectum. Here, we identified the polyketide synthase (PKS) FmPKS40 to be involved in fusapyrone biosynthesis, delineate putative cluster borders by co-expression studies and provide insights into its regulation.

Evaluation of Fungicides and Plant Extracts Against Pathogenic Fungi Associated With Basella Spp.

Five fungicides viz., CM 75, Dithane M 45, Knowin 50 WP, Nativo 75 WG and Rovral 50 WP were evaluated against Colletotrichum lindemuthianum, Drechslera sacchari and Fusarium semitectum following poisoned food technique. Out of five fungicides complete inhibition of radial growth of C. lindemuthianum was observed in Nativo 75 WG at 100 ppm. On the other hand, the complete inhibition of the growth of D. sacchari was observed with Rovral 50 WP at 400 ppm, whereas Nativo 50 WP showed complete growth inhibition at 500 ppm. CM 75 WP, Knowin 50 WP and Nativo 75 WG showed complete growth inhibition of F. semitectum at 100 ppm. Five different plant leaf extracts viz., Azadirachta indica A. Juss., Heliotropium indicum L., Lippia alba L., Michelia champaca L. and Thuja occidentalis L. were tested against the test pathogens. Of the five plant leaf extracts, Lippia alba showed the highest growth inhibition in C. lindemuthianum, D. sacchari and F. semitectum at 20% concentration. Asiat. Soc. Bangladesh, Sci. 46(1): 81-89, June 2020

Mycoflora associated with infected plant parts of Tagetes erecta L. and Tagetes patula L.

Twenty species of fungi associated with blight symptom of different plant parts of Tagetes erecta L. and T. patula L. have been described. The associated fungi were Alternaria alternata (Fr.) Keissler, Aspergillus flavus Link, A. fumigatus Fresenius, A. niger van Tieghem, Bipolaris australiens is (M.B. Ellis) Tsuda &Ueyama, Chaetomium globosum Kunze, Cladosporium elatum (Harz) Nannf., Corynespora cambrensis M. B. Ellis, Curvularia brachyspora Boedijn, C. fallax Boedijn, C. lunata (Wakker) Boedijn, C. stapeliae(du Plessis) Hughes &du Plessis, Epicoccum purpuras cens Ehrenb. ex Schlecht,, Fusarium semitectum Berk. & Rav., Monochaetia ceratoniae (Sousa da Camera) Sutton, Nigrospora panici Zimm., Penicillium italicum Wehmer, Rhizopus stolonifer (Ehrenb.: Fr.) Vuill, Trichoderma viride Pers. and Trichothecium roseum Link.

Synthesis and Investigation of Tetrahydro-β-carboline Derivatives as Inhibitors of Plant Pathogenic Fungi

A series of tetrahydro-ß-carbolines substituted with an alkyl or acyl side chain was synthesized and screened for its antifungal activity against plant pathogenic fungi (Bipolaris oryzae, Curvularia lunata, Fusarium semitectum, and Fusarium fujikuroi). The structure activity relationship revealed that the substituent at the piperidine nitrogen plays an important role for increasing antifungal activities. In this series, 2-octyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole (3g) displayed potent antifungal activities with a minimum inhibitory concentration of 0.1 μg/mL, including good inhibitory activity to the radial growth of fungus at a concentration of 100 μg/mL compared to amphotericin B.

Prevalence and Pathogenic Potentiality of Fungi Associated With Leaf Spot of Basella Alba and B. Rubra

Two major species of Indian spinach, namely Basella alba L. and B. rubra L. were selected to find out associated mycoflora and their pathogenic potentiality. Ten fungi viz., Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, Colletotrichum dematium, C. lindemuthianum, Curvularia lunata, Drechslera sacchari, Fusarium semitectum and Penicillium sp. were found to be associated with the selected leaves of Basella spp. Among the isolated fungi C. lindemuthianum, D. sacchari and F. semitectum were found to be pathogenic to Basella spp. Association of C. lindemuthianum and D. sacchari with Basella spp. are recorded first time from Bangladesh. Dhaka Univ. J. Biol. Sci. 29(2): 183-189, 2020 (July)

Inventarisasi Jamur Patogen Tular-Benih pada Lima Varietas Padi

Penelitian ini bertujuan untuk mengetahui (1) beragam spesies jamur patogen tular-benih pada lima varietas padi, dan (2) persentase daya kecambah lima varietas padi. Penelitian dilaksanakan di Laboratorium Karantina Pertanian Kelas I Semarang, dari bulan Maret sampai dengan Mei 2019. Penelitian ini menggunakan Rancangan Acak Lengkap dengan 5 perlakuan dan 5 ulangan, perlakuan terdiri atas Varietas Inpago Unsoed 1, Inpago Unsoed Parimas, IR64, Ciherang, dan Situ Bagendit. Isolasi dan identifikasi jamur patogen tular-benih dilakukan pada blotter test dan medium PDA, dengan pengamatan di bawah mikroskop stereo dan kompon, kemudian dibandingkan dengan pustaka. Variabel yang diamati yaitu morfologi koloni patogen, morfologi patogen, dan daya kecambah. Hasil penelitian menunjukkan bahwa (1) pada semua varietas benih padi terdapat jamur patogen tular-benih, tetapi tidak semua jamur tersebut dijumpai pada setiap varietas. Jenis jamur patogen tular-benih yang dijumpai, yaitu Alternaria padwickii Ganguly, Aspergillus flavus Link, Aspergillus niger van Tieghem, Curvularia lunata (Wakker) Boedjin, Curvularia pallescens Boedjin, Drechslera oryzae Breda de Haan, Fusarium semitectum Berk. & Rav. [W&R, G,B,J], Rhizoctonia solani J. G. Kuhn, Rhizopus oryzae Went & Prins. Geerl., dan Tilletia barclayana Bref., dan (2) uji daya kecambah menunjukkan bahwa masing-masing varietas benih padi memilki persentase daya kecambah benih yang berbeda. Daya kecambah benih berturut-turut pada varietas IR64, Ciherang, Inpago Unsoed 1, Inpago Unsoed Parimas, dan Situ Bagendit sebesar 85,75, 81,75, 80,25, 76,5, dan 70%.

Inventarisasi Jamur Patogen Tular-Benih pada Lima Varietas Padi

Penelitian ini bertujuan untuk mengetahui (1) beragam spesies jamur patogen tular-benih pada lima varietas padi, dan (2) persentase daya kecambah lima varietas padi. Penelitian dilaksanakan di Laboratorium Karantina Pertanian Kelas I Semarang, dari bulan Maret sampai dengan Mei 2019. Penelitian ini menggunakan Rancangan Acak Lengkap dengan 5 perlakuan dan 5 ulangan, perlakuan terdiri atas Varietas Inpago Unsoed 1, Inpago Unsoed Parimas, IR64, Ciherang, dan Situ Bagendit. Isolasi dan identifikasi jamur patogen tular-benih dilakukan pada blotter test dan medium PDA, dengan pengamatan di bawah mikroskop stereo dan kompon, kemudian dibandingkan dengan pustaka. Variabel yang diamati yaitu morfologi koloni patogen, morfologi patogen, dan daya kecambah. Hasil penelitian menunjukkan bahwa (1) pada semua varietas benih padi terdapat jamur patogen tular-benih, tetapi tidak semua jamur tersebut dijumpai pada setiap varietas. Jenis jamur patogen tular-benih yang dijumpai, yaitu Alternaria padwickii Ganguly, Aspergillus flavus Link, Aspergillus niger van Tieghem, Curvularia lunata (Wakker) Boedjin, Curvularia pallescens Boedjin, Drechslera oryzae Breda de Haan, Fusarium semitectum Berk. & Rav. [W&R, G,B,J], Rhizoctonia solani J. G. Kuhn, Rhizopus oryzae Went & Prins. Geerl., dan Tilletia barclayana Bref., dan (2) uji daya kecambah menunjukkan bahwa masing-masing varietas benih padi memilki persentase daya kecambah benih yang berbeda. Daya kecambah benih berturut-turut pada varietas IR64, Ciherang, Inpago Unsoed 1, Inpago Unsoed Parimas, dan Situ Bagendit sebesar 85,75, 81,75, 80,25, 76,5, dan 70%.

Thyme (Thymus vulgaris L.) Root Rot/Wilt in Minia Governorate, Egypt

Thyme (Thymus vulgaris L.) is a medicine and aromatic plant, have a great economic important due to the great income that it provides and other diversified usages. Damping-off, root rot and wilt symptoms were observed in field thyme grown in Maghagha and Beni Mazar districts, Minia Governorate, Egypt, during November to March, 2016-2017. Survey, sampling and pathogenicity tests were carried out. Fusarium semitectum, F. solani, Rhizoctonia solani and Macrophomina phaseolina were the dominant pathogens causing thyme damping off, root rot and wilt. The inhibitory effect of two resistance inducer substances (salicylic and ascorbic acids) three fungicides (Cure M 72% WP, Rizolex Ex-T 50% WP and Rolex 50% WP) on the growth of the most pathogenic fungi in vitro was investigated. Salicylic acid inhibited the growth of F. semitectum and R. solani completely at 200ppm but the growth of M. phaseolina was completely inhibited at 400ppm. The complete inhibition for the growth of all tested pathogens was occurred at 400 ppm Ascorbic acid. F. semitectum and R. solani were more sensitive to Rizolex T, while M. phaseolina was more sensitive to Cure-M, (causing the lowest diameter averages The results of the present investigation showed the possibility to use certain antioxidants as fungicides alternatives to control plant pathogenic fungi. According to the available literature, this is a first study on thyme root rot/wilt in Egypt.

The inhibitory effect of Eupatorium adenophorum extracts on the pathogen of postharvest disease of banana

The Colletotrichum musae and Fusarium semitectum Berk., Which often occur in banana after harvest were used as the targets. Three components with antibacterial activity extracted from the leaves of the plant were used as "fungicide". The antibacterial effect of the three component substances on the pathogens of anthracnose and shaft rot was studied. The results showed that the inhibitory rates of the components A, B and C at 2 mg / ml on the pathogens of banana anthracnose and shaft rot reached 82.53%, 79.91%, 78.30% and 82.2%, 78.69% and 81.17% respectively. The EC90 values of component A, B and C for banana anthracnose pathogens were 1.70, 1.85, and 1.69 mg / ml. Respectively, the EC90 values for banana shaft rot pathogens were 1.37, 1.38, and 1.64 mg / ml. The antibacterial effect of the three component substances on the pathogen of banana shaft rot was better than that of anthracnose. The three component substances have great potential for controlling post-harvest anthracnose and shaft rot of bananas.