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Abstract
Nematophagous fungi have long been considered a potential biological agent for the control of nematodes. Based on conidia and conidiophores morphology, these fungi have been classified into a number of genera. Paecilomyces lilacinus are soil-borne fungi with greater potential for use as a biological control agent against plant-parasitic nematodes, and they have a high frequency of occurrence in the tropics and subtropic regions of the world and also in most agricultural soils. P.lilacinus has been reported to reduce nematode populations and has been considered the most effective biocontrol agent for the management of plant-parasitic nematodes. Based on 18S rRNA gene, internal transcribed spacer (ITS), and partial translation elongation factor 1-α (TEF) sequences, the Paecilomyces lilacinus is classified with the new genus name Purpureocillium. Phylogenetic reports identified the P. lilacinum, which was earlier erroneously grouped with Paecilomyces under the order Eurotiales, which now belongs to the Ophiocordycipitaceae family in the order Hypocreales. P. lilacinum produce diversified secondary metabolites like serine protease, chitinase, acetic acid, small chain fatty acids, and antibiotics such as lilacin and leucinostatins (also known as paecilotoxins). The secondary metabolite, paecilotoxins is considered as a significant compound that plays a major role in controlling nematode populations in soil. Use of fungi P. lilacinum as biocontrol agent either alone or integrated with other nematode management strategies offer an environmentally sustainable method. Investigations are also needed to identify the risk and safety measures for humans during the continuous usage.
... Paecilomyces is a ubiquitous fungus commonly found in food, soil and decaying plants (Senthilkumar et al., 2020). Paecilomyces species are a new class of biocontrol agent with a variety of antimicrobial effects, including parasitism, competition for nutrients, production of bioactive secondary metabolites, and induced disease resistance (Moreno-Gavíra et al., 2020). ...
Colletotrichum brevisporum is a hazardous fungal pathogen that can cause anthracnose disease in several crops. In this study, Paecilomyces maximus NJC01 was isolated from C. brevisporum-infected soybean plants, and identified by ITS and TUB2 sequencing and morphological analysis. Interestingly, NJC01 inhibited the mycelial growth of plant fungal pathogens C. brevisporum, Sclerotinia sclerotiorum, Ceratocystis fimbriata and Valsa pyri. NJC01 showed various antifungal mechanisms against C. brevisporum, including competition for space and nutrients and the production of secondary metabolite genistein, which was detected at 91.8 µg/mL in the culture medium. NJC01 could colonize wounds in soybean pods, maintained its population in the inoculation site, and did not cause necrotic lesions. Combination of 1 × 108 cells/mL NJC01 and heat treatment reduced C. brevisporum lesions by 45%. The first biocontrol strategy for the management of C. brevisporum is reported in this study. This study provides new insights on the use of Paecilomyces species for the biocontrol of anthracnose disease.
An ecosystem contains living organisms all of which depend on the interaction with one another. The rhizosphere housing the root of cultivated crops contains several groups of organisms ranging from microbes to vertebrates. Most of which depend on plants directly or indirectly for their survival. Agricultural crops interact with other organisms present in their environment. Such interactions may be beneficial or harmful to the crops grown in the ecosystem. Biotic component including opportunistic fungi, plant, and nematode influences the metabolisms and yield of cultivated crops. As the crops grow with time in their life cycle, they may be susceptible to the influence of these opportunistic organisms on the field. Factors such as growth stage, unfavourable weather condition, and wounding may reduce the immunity of the plants and therefore leading to the infection of the crop plant by opportunistic organisms. Therefore, this chapter explores the various physical and biochemical interactions between agricultural plant and opportunistic microorganisms.
Mushrooms are important organisms because of their human nutritional and medicinal value. With the expansion of the cultivation of edible mushrooms, fungal diseases have become a major problem in limiting their production. Numerous fungi can cause mushroom deformation or rots. In this publication we report on fungal diseases found during Morchella cultivation in China, with emphasis on morphology and phylogeny to characterise species. The key findings include 1) establishment of a new family Albomorchellophilaceae in Hypocreales, and a novel monotypic genus Albomorchellophila with the type species A. morchellae. Divergence time estimates indicate that Albomorchellophilaceae diverged from its sister family Calcarisporiaceae at ca. 105 (92–120) MYA; 2) the phylogeny and morphology of the family Pseudodiploosporeaceae (Hypocreales) is revised. The family contains a single genus Pseudodiploospora. Intraspecific genetic analyses of Pseudodiploospora longispora reveals significant base differences within strains, especially in the regions of protein-coding genes RPB 2 and TEF; 3) four fungicolous taxa, i.e., Cylindrodendrum alicantinum, Hypomyces aurantius, Hypomyces rosellus, and Trichothecium roseum, are reported as putative pathogens on cultivated morels for the first time. In addition, the previously reported pathogens of morels, Clonostachys rosea, Clonostachys solani, Hypomyces odoratus, and Pseudodiploospora longispora are also detailed in their symptoms and morphology; 4) the phylogeny and morphology of “Zelopaecilomyces” previously placed within Pseudodiploosporeaceae are re-assessed. “Zelopaecilomyces” is proved to be introduced through a chimerism of gene fragments sourced from two distinct organisms. Consequently, it is recommended that “Zelopaecilomyces” should not be recognised due to the mixed up molecular data in phylogeny and a lack of support from morphological evidence. Furthermore, this study discusses the voucher specimen Paecilomyces penicillatus (CBS 448.69), which may contain two mixed taxa, i.e., Pseudodiploospora longispora and a member of Penicillium. Publications on pathogenic fungi of cultivated mushrooms is sporadically, which leads to a lack of understanding of causal agents. As a follow up to the diseases of morel cultivation, we also review the fungal diseases of cultivated mushrooms reported over the last four decades. More than 130 pathogens affect the growth and development of the main cultivated mushrooms. The taxonomic diversity of these pathogens is high, distributed in 58 genera, 40 families, 20 orders, 12 classes and six phyla. The host infected are from Ascomycota to Basidiomycota, mainly being reported from Agaricus bisporus, Cordyceps militaris, Morchella spp., and Pleurotus spp. This study not only enriches our current knowledge on the diversity of pathogens of cultivated mushrooms, especially morels, but also recognizes the importance of some taxa as potential pathogens. Taxonomic investigation and accurate identification are initial and key steps to understanding pathogen-mushroom interactions, and will result in better disease management strategies in the mushroom industry.
Pesticides play a pivotal role in agriculture for the effective production of various crops. The indiscriminate use of pesticides results in the significant bioaccumulation of pesticide residues in vegetables. This situation is beyond the control of consumers and poses a serious health issue for human beings. Occupational exposure to pesticides may occur for farmers, agricultural workers, and industrial producers of pesticides. This occupational exposure primarily causes food and water contamination that gets into humans and environmental pollution. Depending on the toxicity of pesticides, the causes and effects differ in the environment and in human health. The number of criteria used and the method of implementation employed to assess the effect of pesticides on humans and the environment have been increasing, as they may provide characterization of pesticides that are already on the market as well as those that are on the way. The biological control of pests has been increasing nowadays to combat all these effects caused by synthetic pesticides. Myco-biocontrol has received great attention in research because it has no negative impact on humans, the environment, or non-target species. Entomopathogenic fungi are microbes that have the ability to kill insect pests. Fungi also make enzymes like the lytic enzymes, esterase, oxidoreductase, and cytochrome P450, which react with chemical residues in the field and break them down into nontoxic substances. In this review, the authors looked at how entomopathogenic fungi break down insecticides in the environment and how their enzymes break down insecticides on farms.
The nomenclatural status and history of the generic name Isaria are reviewed. Authorship and typification are discussed, and we conclude that Isaria Pers.: Fr. is a validly published generic name that has previously been effectively and appropriately lectotypified by Isaria farinosa (Holm: Fr.) Fr. A lectotype illustration and an epitype specimen are designated for I. farinosa. We suggest that the name Isaria be used for species previously assigned to Paecilomyces section Isarioidea Samson. Further taxonomic studies are required to determine the appropriate circumscription of Isaria. Our conclusions preserve a Friesian genus in a familiar sense.