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Vigna radiata L., an imperative legume crop of Pakistan, faces hordes of damage due to fungi; infecting host tissues by the appressorium. The use of natural compounds is an innovative concern to manage mung-bean fungal diseases. The bioactive secondary metabolites of Penicillium species are well documented for their strong fungi-static ability against many pathogens. Presently, one-month-old aqueous culture filtrates of Penicillium janczewskii, P. digitatum, P. verrucosum, P. crustosum, and P. oxalicum were evaluated to check the antagonistic effect of different dilutions (0, 10, 20, ... and 60%). There was a significant reduction of around 7–38%, 46–57%, 46–58%, 27–68%, and 21–51% in Phoma herbarum dry biomass production due to P. janczewskii, P. digitatum, P. verrucosum, P. crustosum, and P. oxalicum, respectively. Inhibition constants determined by a regression equation demonstrated the most significant inhibition by P. janczewskii. Finally, using real-time reverse transcription PCR (qPCR) the effect of P. Janczewskii metabolites was determined on the transcript level of StSTE12 gene involved in the development and penetration of appressorium. The expression pattern of the StSTE12 gene was determined by percent Knockdown (%KD) expression that was found to be decreased i.e. 51.47, 43.22, 40.67, 38.01, 35.97, and 33.41% for P. herbarum with an increase in metabolites concentrations viz., 10, 20, 30, 40, 50 and 60% metabolites, respectively. In silico studies were conducted to analyze the role of Ste12 a transcriptional factor in the MAPK signaling pathway. The present study concludes a strong fungicidal potential of Penicillium species against P. herbarum. Further studies to isolate the effective fungicidal constituents of Penicillium species through GCMS analysis and determination of their role in signaling pathways are requisite. [ABSTRACT FROM AUTHOR]

Leaf necrosis is a common fungal problem of plants. During a survey of Lahore, Dracaena Red Edge (Dracaena mariginata Lam.) and Sow thistle (Sonchus oleraceus L.) were infected with leaf spots. Pathogens isolation from the infected leaves of both plants was done followed by confirmation of Koch's pathogenicity postulates. Based on morphological and genetic characterization, Alternaria arborescens Simmons. and Phyllosticta aristolochiicola R.G. Shivas. were isolated from D. mariginata and S. oleraceus, respectively. In addition to isolation and identification, biological control of both pathogens was conducted using methanol extract of Cinnamon (Cinnamomum verum J. Presl.). All concentrations of extract suppressed the growth of both pathogens to variable extent. In case of A. arborescens, 0.5% concentration induced approximately 90% suppression in fungal growth. Contrastingly, P. aristolochiicola was least affected at lower concentrations of extract as only 4-10% arrest in fungal biomass production was recorded at 0.5-1.5% concentrations. However, 2.0% or more of the extract was most potent as fungal pathogens failed to grow at these concentrations. Therefore, Cinnamon extract was considered more effective in controlling A. arborescens than P. aristolochiicola. Further, studies are required to identify active antifungal compounds in Cinnamon crude extract against the target pathogens. [ABSTRACT FROM AUTHOR]

Combretum indicum leaf spot disease was observed during a survey of horticultural plants in Lahore. Isolation of causal organism was carried out from the disease leaves. The pathogen, Alternaria brassicae, was first identified considering morphological characters. The morphology based identification was confirmed by nucleotide sequence analysis of ITS region of rDNA and phylogentic analysis of this fungus with closely related other fungal species. Pathogenicity of A. brassicae was verified following the Koch's Pathogenicity postulates. This report represents the first record of leaf spot of Combretum indicum by Alternaria brassicae from Pakistan. [ABSTRACT FROM AUTHOR]

Tomato (Lycopersicon esculentum Mill.) is one of the most popular and significant commercial crop of Pakistan. Outbreak of leaf spot was observed on leaves of tomato plants growing in fields of Lahore. Causal organism was isolated and initially identified on the basis of morphological characters. Complete description of macro and microscopic characters was prepared. Identification was confirmed by rDNA spacer sequence. Based on morphological and molecular approaches, Alternaria metachromatica was identified as causal organism. Culture of pathogen was deposited in First Fungal Culture Bank of Pakistan (FCBP) and the gene sequence in GenBank. Pathogenicity was confirmed by exposing the healthy leaves to spores of A. metachromatica as well as inoculums in the soil. [ABSTRACT FROM AUTHOR]