Medically Important Fungi: A Guide to Identification

Agricultural productivity suffers a heavy loss due to plant pathogens, insect pests and various abiotic stresses. Agriculture being the world’s largest economic sector, it is the need of time to find and establish the ideal strategy for sustainable agriculture and improvement in crop growth. Endophytes are microorganisms that asymptomatically grow within the plant tissues without causing any disease to the host. Endophytic fungi live in symbiotic association with plants and play an important role in plant growth promotion, higher seed yield and plants resistant to various biotic, abiotic stresses and diseases. Many are able to produce antimicrobial compounds, plant growth hormones and various agrochemical bioactive metabolites. These mycoendophytes hold enormous potential for the development of eco-friendly and economically viable agricultural products. In this review we focused on the endophytic fungi recovered from different medicinal plants, their active principles involved in plant growth enhancement and the applications of fungal endophytes in agriculture. Moreover, we also discussed about endophytic fungi and their pragmatic approach towards sustainable food and agriculture.

Fungal growth promotor endophytes: a pragmatic approach towards sustainable food and agriculture

Some specialist insects feed on plants rich in secondary compounds, which pose a major selective pressure on both the phytophagous and the gut microbiota. However, microbial communities of toxic plant feeders are still poorly characterized. Here, we show the bacterial communities of the gut of two specialized Lepidoptera, Hyles euphorbiae and Brithys crini, which exclusively feed on latex-rich Euphorbia sp. and alkaloid-rich Pancratium maritimum, respectively. A metagenomic analysis based on high-throughput sequencing of the 16S rRNA gene revealed that the gut microbiota of both insects is dominated by the phylum Firmicutes, and especially by the common gut inhabitant Enterococcus sp. Staphylococcus sp. are also found in H. euphorbiae though to a lesser extent. By scanning electron microscopy, we found a dense ring-shaped bacterial biofilm in the hindgut of H. euphorbiae, and identified the most prominent bacterium in the biofilm as Enterococcus casseliflavus through molecular techniques. Interestingly, this species has previously been reported to contribute to the immobilization of latex-like molecules in the larvae of Spodoptera litura, a highly polyphagous lepidopteran. The E. casseliflavus strain was isolated from the gut and its ability to tolerate natural latex was tested under laboratory conditions. This fact, along with the identification of less frequent bacterial species able to degrade alkaloids and/or latex, suggest a putative role of bacterial communities in the tolerance of specialized insects to their toxic diet.

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The Generalist Inside the Specialist: Gut Bacterial Communities of Two Insect Species Feeding on Toxic Plants Are Dominated by Enterococcus sp.

The farming of edible insects is an alternative strategy for the production of protein-rich food and feed with a low ecological footprint The industrial production of insect-derived protein is more cost-effective and energy-efficient than livestock farming or aquaculture The mealworm Tenebrio molitor is economically among the most important species used for the large-scale conversion of plant biomass into protein Here, we review the mass rearing of this species and its conversion into food and feed, focusing on challenges such as the contamination of food/feed products with bacteria from the insect gut and the risk of rapidly spreading pathogens and parasites We propose solutions to prevent the outbreak of infections among farmed insects without reliance on antibiotics Transgenerational immune priming and probiotic bacteria may provide alternative strategies for sustainable insect farming

https://www.degruyter.com/downloadpdf/j/znc.2017.72.issue-9-10/znc-2017-0033/znc-2017-0033.xml

Sustainable farming of the mealworm Tenebrio molitor for the production of food and feed.

Transient endophytic colonizations of plants improve the outcome of foliar applications of mycoinsecticides against chewing insects.

The corrosion inhibition investigation of aerial extract of Cnicus Benedictus , a weed referring to the Asteraceae family has been evaluated on the mild steel corrosion in 0.5 M HCl with the employment of the weight-loss method, potentiodynamic polarization measurements (PDP) and electrochemical impedance spectroscopy (EIS) techniques. This investigation demonstrated Cnicus Benedictus extract (CBE) as a green and sustainable mild steel corrosion inhibitor in 0.5 M HCl media exhibiting an inhibition efficacy of 92.45% at 1000 ppm. With the increased concentration of CBE, the value of i corr and corrosion rate (C R ) decreased significantly from 7.4114 to 0.97438, revealing the protective effect of CBE on mild steel. The deposition of a highly defensive coating on the mild steel surface was demonstrated by the contact angle measurements. Additionally, the increase in the K ads values indicated a stronger interaction between the inhibitor molecules and metal surface. Furthermore, density functional theory (DFT) and Monte Carlo simulations have been utilized to validate the significant inhibition characteristic attained by the experimental study and to suggest an adsorption mechanism. 

Computational and Experimental studies on the corrosion inhibition performance of an aerial extract of Cnicus Benedictus weed on the acidic corrosion of mild steel

Suppressing inhibitory compounds by nanomaterials for highly efficient biofuel production: A review

Pathogenicity of bacteria isolated from gut of Spodoptera litura (Lepidoptera: Noctuidae) and fitness costs of insect associated with consumption of bacteria.

Endophytic fungi, which live within host plant tissues without causing any visible symptom of disease, are important mediators of plant-herbivore interactions. These endophytes enhance resistance of host plant against insect herbivores mainly by productions of various alkaloid based defensive compounds in the plant tissue or through alterations of plant nutritional quality. Two endophytic fungi, i.e., Nigrospora sp. and Cladosporium sp., were isolated from Tinospora cordifolia (Thunb.) Miers, a traditional indian medicinal plant. Cauliflower (Brassica oleracea L.) plants were inoculated with these two endophytic fungi. The effect of endophyte infected and uninfected cauliflower plants were measured on the survival and development of Spodoptera litura (Fab.), a polyphagous pest. Endophyte infected cauliflower plants showed resistance to S. litura in the form of significant increase in larval and pupal mortality in both the fungi. Inhibitory effects of endophytic fungi also were observed on adult emergence, longevity, reproductive potential, as well as hatchability of eggs. Thus, it is concluded that antibiosis to S. litura could be imparted by artificial inoculation of endophytes and this could be used to develop alternative ecologically safe control strategies.

https://bioone.org/journals/Environmental-Entomology/volume-42/issue-2/EN12001/Enhanced-Resistance-to-iSpodoptera-litura-i-in-Endophyte-Infected-Cauliflower/10.1603/EN12001.pdf

Enhanced Resistance to Spodoptera litura in Endophyte Infected Cauliflower Plants

Addition of antibiotics to artificial diets of insects is a key component in the rearing of insects in the laboratory. In the present study an antimicrobial agent, streptomycin sulphate was tested for its influence on survival and fitness of Spodoptera litura (Fabricus) (Lepidoptera: Noctuidae) as well as its gut microbial diversity. The antibiotic did not adversely affect the survival of S. litura. Faster growth of larvae was recorded on diet amended with different concentrations of streptomycin sulphate (0.03, 0.07 and 0.15%) as compared to diet without streptomycin sulphate. The overall activity of various digestives enzymes increased on S+ diet while the activity of detoxifying enzymes significantly decreased. In addition, alteration in microbial diversity was found in the gut of S. litura larvae fed on diet supplemented with antibiotic (S+) and without antibiotic (S−).

Abhinay Thakur

Papers

Computational and Experimental studies on the corrosion inhibition performance of an aerial extract of Cnicus Benedictus weed on the acidic corrosion of mild steel

Suppressing inhibitory compounds by nanomaterials for highly efficient biofuel production: A review

Pathogenicity of bacteria isolated from gut of Spodoptera litura (Lepidoptera: Noctuidae) and fitness costs of insect associated with consumption of bacteria.

Enhanced Resistance to Spodoptera litura in Endophyte Infected Cauliflower Plants

Effect of antibiotic on survival and development of Spodoptera litura (Lepidoptera: Noctuidae) and its gut microbial diversity.