Infection of Galleria mellonella (Lepidoptera) Larvae With the Entomopathogenic Fungus Conidiobolus coronatus (Entomophthorales) Induces Apoptosis of Hemocytes and Affects the Concentration of Eicosanoids in the Hemolymph

Apoptosis and autophagy, the mechanisms of programmed cell death, play critical roles in physiological and pathological processes in both vertebrates and invertebrates. Apoptosis is also known to play an important role in the immune response, particularly in the context of entomopathogenic infection. Of the factors influencing the apoptotic process during infection, two of the lesser known groups are caspases and eicosanoids. The aim of this study was to determine whether infection by the entomopathogenic soil fungus Conidiobolus coronatus is associated with apoptosis and changes in caspase activity in the hemocytes of Galleria mellonella larvae, and to confirm whether fungal infection may affect eicosanoid levels in the host. Larvae were exposed for 24 h to fully grown and sporulating fungus. Hemolymph was collected either immediately after termination of exposure (F24 group) or 24 h later (F48 group). Apoptosis/necrosis tests were performed in hemocytes using fluorescence microscopy and flow cytometry, while ELISA tests were used to measure eicosanoid levels. Apoptosis and necrosis occurred to the same degree in F24, but necrosis predominated in F48. Fungal infection resulted in caspase activation, increased PGE1, PGE2, PGA1, PGF2α, and 8-iso-PGF2α levels and decreased TXB2 levels, but had no effect on TXA2 or 11-dehydro-TXB2 concentrations. In addition, infected larvae demonstrated significantly increased PLA2 activity, known to be involved in eicosanoid biosynthesis. Our findings indicate that fungal infection simultaneously induces apoptosis in insects and stimulates general caspase activity, and this may be correlated with changes in the concentrations of eicosanoids.

The effect of Soil properties on the Biological Diversity of Fungi in Soil University of Anbar.

Microorganisms are a varied collection of organisms that make up around 60% of the earth’s biomass. The ratio of fungal to plant species is estimated to be around 6 to 1. In order to extrapolate worldwide estimates of 1.5 million fungal species, this ratio is utilized. Because of the activity of soil organisms, soils are very complex systems with numerous components performing many roles. Soil microflora is essential for assessing soil conditions and encouraging plant development. Microorganisms are helpful in enhancing soil fertility because they participate in a variety of biochemical transformation and mineralization processes in soils. Organic matter in the soil that impacts the physical, chemical, and biological characteristics of the soil and serves as a complementary medium for biological processes and life support in the soil environment. Microbes have a very significant role in biodiversity. Organic matter in the soil that influences its physical, chemical, and biological properties and acts as a complimentary medium for biological activities and life support in the soil environment. Microbes play an important part in biodiversity. The study demonstrated the importance of pH and soil texture on the variety of soil fungus species. Three clones were grown on PDA at 28 C° (7 clays) as Aspergillus sp., Penicillium sp., and Fusarium sp.

The effect of trichoderma harzianum dose and shallot population (Allium cepa L.) on chili production (Capsicum annuum L.) by intercropping system

Trichoderma harzianum is a soil fungus that plays a role in decomposing soil organic matter, and contains several components of substances such as N, P, S and Mg and nutrients needed by plants for their growth. Intercropping is one way to increase the efficiency of land use by planting several types of plants on the same land and at the same time. Meanwhile, to increase land use efficiency and reduce the risk of chili farming failure, it can be achieved by implementing an intercropping system of chili with shallots. The research aimed to determine of T.harzianum dosage and the shallots population (Allium cepa L.). The interaction between these on the chili production (Capsicum annuum L.) by intercropping system. The experimental design used was Randomized Block Design 4 × 3 factorial with three replications. Threre were interactions between T. harzianum dosage and shallots population on fruits number per plant, fruit weight per plant and fruit length per plant. The best result were found at 20 g per plant T. harzianum dosage and two shallots population on fruits number per plant (153,33 fruit), fruit weight per plant (121,55 g) and fruit length per plant (126,41 cm).

The Impact of the Entomopathogenic Fungus Conidiobolus coronatus on the Free Fatty Acid Profile of the Flesh Fly Sarcophaga argyrostoma

The chemical composition of the insect cuticle varies remarkably between species and their life stages. It can affect host resistance and substrate utilization by invading entomopathogen fungi, such as the soil fungus Conidiobolus coronatus. In this study, Sarcophaga argyrostoma flies were exposed to sporulating C. coronatus colonies for 24 h; the pupae were resistant, but the adults demonstrated 60% mortality. Although the pupae demonstrated no sign of infection nor any abnormal development, our findings indicate that after 24 h of contact with the fungus, the pupae demonstrated a 25.2-fold increase in total cuticular free fatty acids (FFAs) and a 1.9-fold decrease in total internal FFAs. Also, the cuticular FFA increased from 26 to 30, while the internal FFA class increased from 13 to 23. In exposed adults, the total mass of cuticular FFAs increased 1.7-fold, while the number of FFAs stayed the same (32 FFAs). Also, the internal FFA class increased from 26 to 35 and the total FFA mass increased 1.1-fold. These considerable differences between adults and pupae associated with C. coronatus exposure indicate developmental changes in the mechanisms governing lipid metabolism and spatial distribution in the organism, and suggest that cuticular lipids play a vital role in the defence against pathogenic fungi.

Weak impact of microorganisms on Ca, Mg-bearing silicate weathering

Assessment of the microbial impact on mineral dissolution is crucial for a predictive understanding of basic (Ca, Mg bearing) silicate weathering and the associated CO2 consumption, bioerosion, and CO2 storage in basaltic rocks. However, there are controversies about the mechanism of microbial effect, which ranges from inhibiting via nil to accelerating. Here we studied diopside interaction with the heterotrophic bacterium Pseudomonas reactants and the soil fungus Chaetomium brasiliense using a combination of mixed-flow and batch reactors and in situ (AFM) and ex situ (SEM) microscopy. The results provide new nano-level insights into the degree to which microorganisms modify silicate dissolution. Taking into account negligible effects of organic ligands on diopside dissolution as reported earlier, we conclude that the microbial effect on Ca-Mg silicates is weak and the acceleration of dissolution of “basic” silicate rocks in the presence of soil biota is solely due to pH decrease in porewaters.

Fungal Mobilization of Selenium in the Presence of Hausmannite and Ferric Oxyhydroxides

Bioleaching of mineral phases plays a crucial role in the mobility and availability of various elements, including selenium. Therefore, the leachability of selenium associated with the surfaces of ferric and manganese oxides and oxyhydroxides, the prevailing components of natural geochemical barriers, has been studied in the presence of filamentous fungus. Both geoactive phases were exposed to selenate and subsequently to growing fungus Aspergillus niger for three weeks. This common soil fungus has shown exceptional ability to alter the distribution and mobility of selenium in the presence of both solid phases. The fungus initiated the extensive bioextraction of selenium from the surfaces of amorphous ferric oxyhydroxides, while the hausmannite (Mn3O4) was highly susceptible to biodeterioration in the presence of selenium. This resulted in specific outcomes regarding the selenium, iron, and manganese uptake by fungus and residual selenium concentrations in mineral phases as well. The adverse effects of bioleaching on fungal growth are also discussed.