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The study was aimed to evaluate the effect of essential oils against fungal pathogens including the chemical analysis (GC-MS) of the most effective essential oil.

Blue mold caused by Penicillium species is a major fungal disease threatening the viticulture industry in Pakistan, responsible for deteriorating the quality of grapes during handling, transportation, and distribution. Identification-based approaches of Penicillium species provide a better strategy on accurate diagnosis and effective management. In this study, 13 isolates were recovered from symptomatic grape bunches at five main fruit markets of Rawalpindi district, Punjab province. Based on morphological data and multi-loci phylogenetic analysis, the isolates were identified as two distinct species viz. Penicillium expansum (eight isolates) and Penicillium crustosum (five isolates). Meanwhile, the pathogenicity test of Penicillium isolates presented by the inoculation of grape bunches showed various degrees of severity. For improving the fruit quality and eliminating the needs of synthetic fungicides, botanicals such as thyme (Thymus vulgaris L.), fennel (Foeniculum vulgare L.), garlic (Allium sativum L.), ginger (Zingiber officinale L.), and carum (Carum capticum L.) essential oils (EOs) at concentrations of 0.6, 0.9, 1.2, and 1.5 mg/mL were evaluated. In vitro studies indicated that thyme EO showed a highly significant reduction of fungal growth. Furthermore, the experiments related to reducing the decay development and average weight loss percentage of grapes revealed similar findings. Based on the results of this study, it is recommended that thyme EO can be used as an eco-friendly botanical fungicide against Penicillium spp. causing blue mold disease.

The present study was specifically designed to develop bio-fungicides that may help mitigate reliance on hazardous synthetic chemicals which give rise to environmental safety concerns. A survey (2021--2022) of local fruit markets in Islamabad, Pakistan included morpho-molecular disease identification. It revealed Penicillium chrysogenum as a major phytopathogenic fungi causing fruit rot. The fungicidal action of plant essential oils might be boosted by the technique of application therefore, nanoencapsulation of essential oil and chitosan was performed. To attain the objective of antimicrobial packaging, essential oil and chitosan tablets were encapsulated in spun bond sachets against P. chrysogenum using a sachet volatile phase technique. In vitro screening of nano encapsulated eucalyptus essential oil showed significant inhibition of radial growth of P. chrysogenum colonies at 1.6 mg · ml-1 followed by 1.4, 1.2 and 1.0 mg · ml-1. Results of Gas Chromatography and Mass Spectrometry revealed the presence of eucalyptol in eucalyptus EO as a major antifungal component. An in vivo experiment analyzing the efficacy of essential oil tablets against pre-inoculated peach fruit with P. chrysogenum at ambient temperatures (7--37°C) showed significant reduction in lesion diameter, disease severity and prolonged shelf-life of peaches of more than 2 weeks. The natural ripening process of peach was not affected by the presence of antifungal sachets as no significant alteration in weight loss of fruit was recorded. The suppressiveness of fungal mycelial growth of P. chrysogenum was directly proportional to increases in E. globulus oil concentration. This research may have a signifi- cant impact on prolonging the shelf-life of peach fruit. [ABSTRACT FROM AUTHOR]

Postharvest fungal rots are a continuous threat to perishable fruits worldwide. Fungal contamination is a significant factor affecting quality of peaches and resulting decline in their quantity. Postharvest health of peaches is of major concern for producers, consumers, marketers, and food industries globally. Early specie level detection of these deteriorating fungal rots is extremely important to adopt timely preventive measures and enhance shelf-life of peaches. In present study five fungal phytopathogenic rots were detected from peaches and identified based on molecular characterization using ITS universal fungal primers, EF-1a and ß-tubulin (benA). Multi-locus characterization revealed fungal rots viz; Fusarium sporotrichioides, Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum and Cladosporium pseudocladosporioides respectively. Phylogenetic tree was constructed in MEGAX software using Neighbour-Joining Method and 1000 bootstrap replicates were selected to represent the evolutionary history of the taxa analyzed. Prior to management of various fungal rots, their accurate diagnosis is compulsory. Our results are significant in developing opportune control strategies from the field to storage hence reducing qualitative and quantitative losses and to enhance shelf-life of peaches. [ABSTRACT FROM AUTHOR]

The effect of edible coatings incorporated with essential oils of cinnamon, basil, and thyme with and without sodium alginate, glycerol, and Tween 80 on the physiochemical, sensory, and shelf life of peach fruit were investigated using the multivariate technique. All coatings retarded the changes in fruit as compared to control samples. Combination of essential oils and alginate were more effective as compared to these chemicals alone. Changes in the physiochemical and sensory attributes were slow at the start while rapid toward the end of storage. Total sugars, pH, Total soluble solids, and weight loss showed a positive correlation. Total sugars, TSS, and pH possessed more than 90% similarity while firmness, vitamin C, radical scavenging activity, and sensory attributes had more than 95% similarity. Thyme and alginate incorporated coatings exhibited maximum shelf life. Findings suggest that the essential oil incorporated edible coatings may enhance the shelf life of peach. Practical applications: Prunus persica (peach) is a perishable commodity like most fresh fruits with a short shelf life. A large amount of fruit is lost after harvest due to its short shelf life and rapid biochemical changes. Different preservation methods exists but they are far from being natural and are neither cost‐effective. For this reason, application of natural edible coatings is an effective way to control the rapid changes in fruit and preserve it, hence, enhancing its shelf life. Coatings were developed with alginates, glycerol, and essential oils of basil, thyme, and cinnamon and applied to preserve the peach quality along with the enhancement of its shelf life. This research is beneficial for the industry personnel, researchers, and consumers who always look for natural sources rather than synthetic. It will further create opportunities for the producers to deliver their fruit wherever they want without much loss in its quality. [ABSTRACT FROM AUTHOR]

Stripe rust in wheat is the most problematic disease damaging the produce severely in wheat growing regions. In this paper findings in recent past related to yellow rust with reference to their application in the management of disease have been debated. In this regard various aspects of breeding for resistance were focused. Pathogen has adopted under the changed climatic scenario brings and disease is observed in the regions where it did not exist earlier. Rising temperatures has increased the irregularity and concentration of precipitation, causing the spread and severity of rust diseases. NB-LRR proteins are expected to play a substantial part in advanced agriculture where yield is the primary goal for screening. Biotechnology has revolutionized in biological sciences including Plant Pathology. Experts are studying the biochemical nature and the signals involved in, a plant's responses to pathogen attack and development of disease. Plant resistance genes are being engineered into plants to defend them from plant diseases. [ABSTRACT FROM AUTHOR]

The lentil (Lens culinaris) is an edible pulse crop and belongs to family Leguminosae. Fungal diseases of lentil are the most important biological constraint to productivity. Out of which Botrytis Gray mold causes significant losses. The present investigation is carried out to characterize Botrytis gray mold on lentil crop. During the survey 11 isolates of Botrytis Cinerea causing grey mold disease was collected different lentil growing areas of Pothwar regions. The isolates were identified on the basis of cultural and microscopic features. After 6 days during cultural studies maximum growth was observed on Czepk and Malt extract medium (85 mm) and minimum growth was on PDA (74.1 mm). The colony color was varies from whitish to black grayish with fluffy texture. Microscopically B. cinerea produces gray mycelium with branched conidiophores that that have rounded apical cells bearing cluster of colorless or gray one celled, ovoid conidia. The conidiophores and cluster of conidia resembles as a grape-like cluster. The pathogenecity test confirmed all the isolates of B. Cinerea were able to cause the gray mold disease. The overall objective of this study is to morphologically characterize the Botrytis cinera that provides a due step for management of Botrytis grey mould disease of lentil crops. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) occupies the second largest area among the oilseed crops after mustard and rapeseed in Pakistan. It is the main legume crop and primarily grown as oilseed crop. Due to the presence of high percentage of fatty acids in its oil, its nutritional properties are considered as favorable for human and animals. In the present study, seed-borne fungi were recovered from four different varieties of peanut with their incidence percentage. Data revealed that all the varieties were affected by the fungal species however, the variety, Golden showed maximum incidence of up to 70% of Aspergillus spp. while the variety BARI-2011 had the least percent incidence of upto15% of Rhizopus spp. Germination test was carried by Standard rolled paper method and minimum growth (8% as healthy seed germination) was observed in Golden and maximum growth in BARI-2011 of 22% as healthy seed germination. Fatty acid profile determination was done by Gas Chromatography percentage of fatty acids were examined and evaluated that the fungal pathogen has an influence on the oil contents and fatty acids in the peanut seeds. The saturated fatty acids were increased and unsaturated fatty acids decreased due to an oxidation process and production of toxic metabolites in the seed which also reduced the germination percentage. It is concluded from the present study that the seed borne fungi are known to affect adversely seed germination and fatty acid composition due to the production of toxic metabolites in the peanut seeds. [ABSTRACT FROM AUTHOR]

A comparative study was conducted on long-term fungal culture preservation methods. A total of eight species (112 isolates) of phytopathogenic fungi (Alternaria alternata, Alternaria solani, Fusarium oxysporum f. sp. lentis, Fusarium oxysporum f. sp. capsici, Rhizoctonia solani, Lasiodiplodia theobromae, Colletotrichum gloeosporioides and Curvularia lunata) belonging to six genera were stored up to 2 years by using five preservation methods (silica gel, cereal grains, mineral oil, soil and distilled water) and their viability was tested periodically after 6, 12, 18 and 24 months. The morphological characters viz. colony diameter, color, texture, topography and sporulation was studied. Each plant pathogenic isolate was considered as viable if morphology of culture was same to the original culture and comparable with the identification keys documented for fungi. Fungal cultures preserved on silica gel had maintained the highest viability as compared to other methods overall. Preservation using soil, and cereal grains was recognized as good storage method. However distilled water and mineral oil storage of some of the preserved cultures showed the least viability after eighteen months. The highest revival percentages after 24 months of preservation for A. alternata and A. solani was by sterile soil (90% and 83.3% respectively), F. oxysporum f. sp. lentis and F. oxysporum f. sp. capsici (93.3% and 92.8% respectively), L. theobromae (77%) and C. lunata (63.6%) by silica gel preservation, R. solani (88.8%) and C. gloeosporioides (85%) by cereal grains. The above least expensive and long term methods for fungal preservation are beneficial for laboratories that have limited resources. [ABSTRACT FROM AUTHOR]

Potato virus Y (PVY) is an emerging problem in main potato growing areas of Pakistan and new molecular tools are necessary for confirmation of PVY. Serological detection of PVY was achieved through Enzyme Linked Immunosorbant Assay (ELISA) and biologically authentication was accomplished on susceptible indicator host plants (Nicotiana tabacum cv. Samsun NN, N. rustica, N. benthamiana and Chenopodium album). Appropriate sense and antisense primers for Capsid Protein (CP) gene were used for molecular diagnosis of PVY in Polymerase Chain Reaction (PCR) and sequence of Pakistani isolate (JQ518267) exhibited 795 nucleotides with maximum composition of adenine followed by guanine, thymine or uracil and cytosine respectively. Physical and chemical properties of CP gene were computed and different bioinformatics tools clearly indicate that amplified gene is hydrophilic, non-allergen and highly conserved region. The final sequence was further compared with ordinary, common, necrotic and recombinant strains of PVY. The phylogenetic tree clearly indicates four different clusters and Pakistani isolate falls in first cluster exhibiting the high degree of nucleotide homology (99.98%) with previously reported isolates of Pakistan. [ABSTRACT FROM AUTHOR]

The present study was carried out to see the effect of potassium bicarbonate and calcium chloride to control postharvest diseases caused by fungi in stored tomato (Solanum lycopersicum L.). Samples of tomato fruit were collected from different places of Rawalpindi district. Eight fungal species namely Alternaria alternata, Aspergillus niger, Cladosporium fulvum, Fusarium oxysporum, Penicillium oxalium, Rhizopus stolonifer, Mucor racemosus and Botrytis cinerea were found in the samples. It was found that among the eight fungal species, M. racemosus and B. cinerea were responsible for significant spoilage and weight loss of stored tomato. Potassium bicarbonate and calcium chloride were applied to these samples at different concentrations viz. 1.5, 2.5 and 3%. It was found that potassium bicarbonate at 2.5% concentration resulted in 6.66% spoilage and 11% weight loss. While it was found that when concentrations of calcium chloride (CaCl2) was increased from 1.5-3.5%, the degree of spoilage and weight loss decreased significantly as well. The results revealed that gradual increase in concentration of applied chemical decreased the degree of spoilage and weight loss in stored tomato. [ABSTRACT FROM AUTHOR]

In the present study, 110 local and 125 imported rice (Oryzae sativa L.) seed samples comprising of 28 different varieties were analyzed for seed health using standard blotter paper method. Eighteen fungal species belonging to 8 fungal genera viz., Alternaria, Bipolaris. Curvularia, Fusarium, Nigrospora, Pyricularia, Phoma and Tellitia were found associated with local and imported paddy seed lots. Local paddy seed lots were found more infected with seed-borne fungi as compared to imported paddy seed lots. On local paddy seed lots, Curvularia lunata (10.2%) was most observed as predominant fungal species followed by Fusarium moniliforme (6.5%). On the other hand, in imported paddy seed lots Tellitia barclyana was found maximum in infection percentage (90%) followed by Fusarium moniliforme (7.6%). [ABSTRACT FROM AUTHOR]

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Intercropping has been considered as a kind of a sustainable agricultural cropping system. In southwest China, maize/soybean strip intercropping has commonly been practised under local limited agricultural land resources. However, heavy rainfall in combination with high humidity and low temperatures cause severe pod and seed deterioration in the maturity and pre-harvesting stages of intercropped soybean. Numerous Fusarium species have been reported as the dominant pathogens of soybean root rot, seedling blight, as well as pod field mold in this area. However, the diversity and pathogenicity of Fusarium species on soybean pods remain unclear. In the current study, diseased soybean pods were collected during the cropping season of 2018 from five different intercropped soybean producing areas. A total of 83 Fusarium isolates were isolated and identified as F. fujikuroi, F. graminearum, F. proliferatum, and F. incarnatum-equiseti species complex based on morphological characteristics and phylogenetic analysis of the nucleotide sequence of EF1-α and RPB2 genes. Pathogenicity tests demonstrated that all Fusarium species were pathogenic to seeds of the intercropped soybean cultivar Nandou12. Fusarium fujikuroi had the maximum disease severity, with a significant reduction of seed germination rate, root length, and seed weight, followed by F. equiseti, F. graminearum, F. proliferatum, and F. incarnatum. Additionally, the diversity of Fusarium species on soybean pods was also considerably distinct according to the geographical origin and soybean varieties. Thus, the findings of the current study will be helpful for the management and resistance breeding of soybean pod decay in the maize/soybean intercropping system. [ABSTRACT FROM AUTHOR]

In June 2015 & 2016, a postharvest survey of table grapes (Vitis vinifera) cv. King's Ruby, was carried out in five different commercial fruit markets of Rawalpindi (33°38'19.2″N, 73°01'45.0″E) district, Punjab Province. Symptoms appeared as brownish lesions with black sporulation on grapes berries. The incidence of these symptoms on bunches ranged from 12 to 17% at all sites. Symptomatic tissue pieces were surface-sterilized with 0.1% sodium hypochlorite (NaOCl) for 30 seconds, rinsed three times with sterile distilled water, dried on filter paper for 45 seconds, and incubated on potato dextrose agar (PDA) at 25°C. After 3 days, dark brown to black mycelium were formed on PDA media. A total of 24 isolates were examined morphologically. The apex of the conidiophore was observed to be radiate. Vesicles were found to be spherical and covered with irregular metulae and phialides. Conidia were globose or subglobose measured (3.14 μm ± 2.24 in averaged diameter: n=50), dark brown to black, with roughened cell walls. The conidiophores were also smooth-walled, hyaline, and became melanized toward the vesicle. These characteristics of the fungus were similar to those described for Aspergillus niger van Tiegh (de Hoog et al. 2000). For molecular identification, the internal transcribed spacer (ITS) region, beta-tubulin (Bt) gene and partial RNA polymerase II largest subunit (RPB2) gene of representative isolate (Asp.n02) was amplified using primers ITS1/ITS4, BT2a/BT2b and RPB2-6F/RPB2-7R respectively (White et al., 1990; Glass & Donaldson, 1995; Liu et al. 1999). Sequences were deposited in GenBank (ITS, MN658871; Bt2, MT117924; and RPB2, MT318289). Based on BLAST analysis, sequences of the ITS region, Bt2 genes, and RPB2 gene showed 99 to 100% similarity of isolate Asp.n02 to Aspergillus niger (Accession Nos. MK307680.1, MN195121.1, MF078661.1 for ITS gene, MN567299.1, MK451029.1, MK451020.1 for Bt2 gene, and MK450788.1, MK450790.1 for RPB2 gene). To complete Koch's postulates, 10-µl aliquots of spore suspensions (106 spores/ml) of isolate: Asp.n 02 was pipetted onto three non-wounded and four wounded (5 mm diam) asymptomatic grape berries cv. King's Ruby (seven berries per isolate), Sterile distilled water was applied to asymptomatic berries similaries to serve as a negative control (Ghuffar et al. 2018; Jayawardena et al. 2018). Berries were incubated at 25 ± 2°C in sterile moisture chambers, and the experiment was conducted twice. Brownish lesions leading to black sporulation similar to the original symptoms were observed on both wounded and non-wounded inoculated berries after 3 days, whereas no symptoms were recorded on the negative control. The morphology of the fungus that was re-isolated from each of the inoculated berries was identical to that of the original cultures. Aspergillus niger was reported previously in Europe and Israel causing mycotoxin (Ochratoxin A) OTA production on Table grapes (Bau et al. 2006). To our knowledge, this is the first report of Aspergillus niger causing black rot of grapes in Pakistan. This finding will help to plan effective disease management strategies against the black rot of grapes in Pakistan.